THE ARTICLES OF WEEK

2010-12-03T09:53:00.000-08:00

What is measles?

Measles is a highly contagious viral disease that can kill you. Although an uncommon disease in the United States of America, in 2008, measles killed 164,000 children worldwide. In most people, the disease produces fever (temperature > 101 F [38.3 C]), a generalized rash that last greater than three days, cough, runny nose (coryza), and red eyes (conjunctivitis). The complications of measles that result in most deaths include pneumonia and inflammation of the brain (encephalitis).

What is rubeola?

Rubeola is the scientific name used for measles. It should not be confused with rubella (German measles).

What is rubella?

Rubella is the scientific name used of German measles, a different viral illness. While German measles is rarely fatal, it is dangerous in that it causes birth defects and can cause miscarriage and fetal death.

What are other names for measles?

Other terms have been used to describe measles. These include (erroneously) rubella, hard measles, red measles, seven-day measles, eight-day measles, nine-day measles, 10-day measles, and morbilli.

What is the history of measles?

Cases of measles were described as early as the seventh century. However, it was not until 1963 that researchers first developed a vaccine to prevent measles. Before the vaccine was made available, almost every child became infected with the virus because it is so easily spread. Before routine vaccination, there were approximately 3-4 million cases of measles and 500 deaths due to measles each year in the United States.

There were initially two types of vaccines developed against measles. One was developed from a virus that had been killed, and the other was developed using a live measles virus that was weakened (attenuated) and could no longer cause the disease. Unfortunately, the killed measles virus (KMV) vaccine was not effective in preventing people from getting the disease, and its use was discontinued in 1967. The live virus vaccine has been modified a number of times to make it safer (further attenuated) and today is extremely effective in preventing the disease. The currently used vaccine is a live attenuated vaccine.

What causes measles?

Measles is caused by the measles virus (a paramyxovirus).

How is measles spread?

Measles is spread through droplet transmission from the nose, throat, and mouth of someone who is infected with the virus. These droplets are sprayed out when the infected person coughs or sneezes. Among unimmunized people exposed to the virus, over 90% will contract the disease. The infected person is highly contagious for four days before the rash appears until four days after the rash appears. The measles virus can remain in the air (and still be able to cause disease) for up to two hours after an infected person has left a room.

How does one become immune to measles?

Anyone who has had measles is believed to be immune for life. People who have received two doses of vaccine after their first birthday have a 98% likelihood of being immune. Infants receive some immunity from their mother. Unfortunately, this immunity is not complete, and infants are at increased risk for infection until they receive the vaccination at 12 to 15 months of age.

Who is at risk for getting measles?

Those people at high risk for measles include:

children less than 1 year of age (although they have some immunity passed from their mother, it is not 100% effective);

people who have not received the proper vaccination series;

people who received immunoglobulin at the time of measles vaccination;

people immunized from 1963 until 1967 with an older ineffective killed measles vaccine.

Are measles deadly?

Measles can kill you. In 2008, approximately 164,000 people died of measles in the world. However, measles is rarely fatal in the United States. This is due to the fact that most people are immunized, which results in very infrequent outbreaks. Also, people most likely to have complications (including death) are those who are malnourished or who have weakened immune systems

What is the danger of getting measles while pregnant?

If you contract measles while you are pregnant, you may have a miscarriage, a stillbirth, or a preterm delivery. There appears to be no risk of having birth defects (unlike an infection with the rubella virus, known as German measles).

If I am exposed, how long does it take to develop symptoms?

The typical time from exposure to a person infected with measles to development of the initial symptoms is 10-12 days (the range is seven to 21 days). The rash occurs a few days after the initial symptoms (ranges from seven to 18 days from exposure).

What are measles symptoms and signs?

The typical case of measles actually starts with a fever, runny nose, hacking cough, and red eyes. After two to four days of these symptoms, the patient may develop spots within the mouth called Koplik's spots. These spots look like little grains of white sand surrounded by a red ring and are usually found inside the cheek toward the back of the mouth (opposite the first and second upper molars).
The skin rash (also known as an exanthem or exanthema) appears three to five days after the onset of the initial symptoms (fever, cough, runny nose, and red eyes). The rash is a flat to slightly raised (maculopapular) red rash that usually last five to six days. It begins at the hairline and then progresses to the face and upper neck. Over the next two to three days, the rash progresses downward to cover the entire body, including the hands and feet. The rash has mostly distinct lesions, but some may overlap (become confluent). Initially, these lesions will turn white when you press on them (blanch). After three to four days, they no longer will blanch. As the rash begins to fade, there will often be a fine flaking of the skin (desquamation). The rash fades in the same order that it appears.
The fever that occurs with measles is called a stepwise fever. The patient starts with a mild fever that progressively gets higher. Fevers often reach temperatures greater than 103 F (39.4 C).
Although not as common as other symptoms, some patients may have a sore throat.

What complications are seen with measles?

Approximately 30% of cases of measles have an associated complication. These complications can include diarrhea (8%), ear infections (7%), pneumonia (6%), blindness (1%), acute brain inflammation (encephalitis) (0.1%), and persistent brain inflammation (subacute sclerosing panencephalitis) (0.0001%).
Blindness associated with measles is due to a combination of poor nutrition (specifically vitamin A deficiency) and the measles infection. Prevention is the most effective treatment. In third-world countries, post-measles blindness is the leading cause of blindness, with up to 60,000 cases occurring annually.
Acute encephalitis, although rare, is extremely dangerous and results in death in approximately 15% of patients who develop it. When it occurs, acute encephalitis generally starts six days after onset of the rash. Symptoms can include fever, headache, vomiting, stiff neck, drowsiness, seizures, and coma.
Subacute sclerosing panencephalitis (SSP) is an extremely rare degenerative condition of the brain and spinal cord (central nervous system). It is believed to be caused by a chronic infection of the central nervous system with the measles virus. Typically, symptoms start years after the patient had measles (average seven years, range one month to 27 years). The patient has a slow and progressive loss of brain function, seizures, and eventually death results. There is no known treatment for SSP.
Most deaths from measles are due to pneumonia in children and encephalitis in adults. There are approximately 2.2 deaths per 1,000 people who get the measles. The people most likely to have complications (including death) are those who are malnourished or who have weakened immune systems (for example, people with AIDS or other conditions that weaken the immune system).

What is atypical measles?

Atypical measles occurs in people who received the killed measles vaccine (KMV; only used from 1963 until 1967) and who are exposed to wild-type measles virus. The KMV unfortunately sensitizes the patient to the measles virus but does not offer any protection. The disease is characterized by fever, pleural effusions, pneumonia, and swelling of the extremities. The rash of atypical measles is different from measles in that it may have an urticarial component (hives) and usually appears first on the ankles and wrists.
It is recommended by the U.S. Centers for Disease Control and Prevention (CDC) that people who may have received the KMV should receive revaccination with the live measles vaccine.
The virus can be isolated in tissue culture in the lab. Blood (serologic) tests are also available.

What is modified measles?

Modified measles is seen in patients who, because they were unimmunized, received immune globulin after being exposed to a patient with measles. It is also seen occasionally in young infants who have limited immunity from their mothers. The immune globulin prolongs the time from exposure to onset of symptoms (incubation period). When the symptoms do occur, they are much milder than those seen with normal measles and tend to last a shorter period of time.

How is the diagnosis of measles made?

The diagnosis of suspected measles is mostly clinical, meaning that the appearance and history of the patient suggest the diagnosis. In a person with known exposure to someone with measles or travel to a foreign country, measles should always be considered when faced with a patient who has high fever and characteristic rash. Until the rash appears, the presence of Koplik's spots should help to suggest the diagnosis. Most cases of suspected measles in the United States turn out not to be measles (see below). It is recommended that the diagnosis be confirmed using a blood test for IgM, a type of antibody against the virus. If the IgM test is positive, viral cultures should be obtained. The state and local health department should be contacted immediately for any suspected case in order to follow the correct procedures for viral culture and isolation of the patient. Further information on laboratory testing of suspected cases is available from the CDC (http://www.cdc.gov/vaccines/pubs/surv-manual/chpt07-measles.htm).

If it is not measles, what else could it be?

There are a large number of infectious diseases and other conditions that can cause some of the symptoms of measles. These include, but are not limited to, dengue fever, drug rashes, enteroviral infections, fifth disease, German measles (rubella), Kawasaki disease, Rocky Mountain spotted fever, roseola, and toxic shock syndrome. It is important that suspected cases be seen by a medical expert and appropriate laboratory tests be ordered.

What should I do if I have been exposed to measles?

People who have been appropriately vaccinated (or who have had the disease) and who are exposed to a patient with measles do not need to do anything. If an unimmunized person is exposed to a patient with measles, they should receive the vaccine as soon as possible. This may prevent the disease if given within 72 hours of exposure. Immune globulin may have some benefit if given within six days of exposure. The CDC recommends that immune globulin be utilized for household contacts of infected people, immunocompromised people, and pregnant women. It is not recommended that immune globulin be utilized to control a measles outbreak.

Is there any treatment for measles after symptoms and signs develop?

The treatment of patients with measles is mostly focused upon symptom relief. Specific complications like pneumonia may require antibiotics. Patients should be on bed rest until the fever has resolved and should remain well hydrated. In malnourished patients, vitamin A supplementation is recommended. Patients should be isolated to prevent spread of the disease.

If measles only rarely occurs in the United States, why should I get vaccinated?

Although measles only rarely occurs in the United States, it still does occur and can be fatal. In the year 2000, almost 1 million children died of the disease. Through a very intensive effort by the World Health Organization, this was decreased to only 164,000 in 2008. When the number of vaccinated individuals starts to decrease, we see the disease start to occur more frequently. This occurred from 1989 until 1991 in the U.S. During that period, there were 55,000 cases and 123 deaths from measles in the U.S. Due to a massive public-health effort, almost all children in the U.S. now receive measles vaccine before they are allowed to enter school. The number of cases of measles in the U.S. dropped to only 37 in 2004. Most cases are now from outside the U.S. (commonly from adopted children from China), although some cases occur as people in this country are exposed to the infected international traveler.

What is the prognosis for measles?

Most people who contract measles will recover completely. Only 2.2 out of 1,000 people who get measles will die. People who are malnourished or immunocompromised are more likely to have complications or die. However, it is possible for any person to die from the measles, which highlights the importance of becoming vaccinated. Almost no one who has been vaccinated has died from the disease.

How can I prevent contracting measles?

The only way to prevent measles is by receiving measles immunization: This is commonly given as a shot containing measles, mumps, and rubella vaccine (MMR) or a shot containing measles, mumps, rubella, and varicella vaccine (MMRV). The MMRV is not recommended for anyone older than 12 years of age. The current recommendation is that everyone receives two doses of the vaccine after 1 year of age. If the vaccine is received before 1 year of age, the person should receive two additional doses.
The measles vaccine is also available as a single vaccine; however, in most cases, there is no reason to utilize the measles vaccine alone without mumps and rubella vaccine. The complete schedule of recommended vaccinations is available from the CDC (http://www.cdc.gov/vaccines/recs/schedules/child-schedule.htm).

Is there any truth to the fear of getting autism from vaccines?

There is no valid scientific evidence that the measles vaccine, or any other vaccine, is the cause of autism. The possibility of an association between the measles vaccine and autism was proposed by Andrew Wakefield and colleagues in 1998. The research published by Wakefield was found to be flawed and actually forged, and the results have not been able to be repeated by other researchers. Since 1998, there have been numerous studies that have examined for such an association. None of these studies have shown any risk of autism associated with the use of the vaccine. A recent study performed in Japan after the MMR vaccine was removed from the market showed that autism continued to increase after the vaccine was no longer being utilized. Although autism is a very serious disease that warrants good research to find out its many causes, not obtaining vaccinations is potentially dangerous and not supported by the best scientific data available today.

Who should not receive measles vaccinations?

The following groups of people should not receive measles vaccinations:

People who have suffered a severe allergic reaction to either the measles vaccine or its components (gelatin or neomycin) should not receive the vaccine.

Women known to be pregnant should not receive the vaccine. Pregnancy should be avoided for four weeks after vaccination.

Severely immunocompromised patients (cancer patients or patients who are receiving large doses of corticosteroids) should not receive the vaccine. However, those leukemia patients who have been in remission for three months may receive the MMR.

Patients with severe human immunodeficiency virus (HIV) infections should not receive the vaccine. However, asymptomatic patients with HIV are considered to be safe for vaccination. The CDC has issued guidelines for vaccination based on the CD4+ T-lymphocyte counts.

People with a moderate to severe acute illness should wait until their illness resolves before receiving the vaccine.

Patients with history of thrombocytopenic purpura or thrombocytopenia (low platelets) may be at increased risk, and immunization should be decided on a case-by-case basis.

If a child has an egg allergy, can they still receive the measles vaccine?

Although the measles vaccine is made using chick embryos, there is no evidence of increased reactions in people with an egg allergy. Therefore the CDC recommends giving MMR vaccine to egg-allergic children without any prior skin testing or the use of special protocols.

What adverse reactions can occur with the measles vaccination?

Adverse reactions to measles vaccination (as part of the MMR) include fever (5%-15%), rash (5%), joint aches (5%), and low platelet count (thrombocytopenia; one instance per 30,000 doses). In adult women, up to 25% will suffer joint pain that is due to the rubella component of the vaccine. The fever usually occurs seven to 12 days after the vaccination, and the rash occurs seven to 10 days after vaccination.

Who should be revaccinated?

The following group of people should be considered unvaccinated and should receive at least one dose of vaccine:

People vaccinated before their first birthday should be revaccinated.

Anyone known to have been vaccinated with the killed measles vaccine (KMV) should be revaccinated.

Anyone vaccinated with KMV who received their dose of live measles vaccine with four months of their last dose of vaccine should be revaccinated.

Anyone vaccinated before 1968 in whom it is not known if the vaccine was KMV or not should be revaccinated.

Where can I find more information about measles?

1. http://wwwn.cdc.gov/travel/yellowBookCh4-Measles.aspx

2. http://www.cdc.gov/vaccines/pubs/
pinkbook/downloads/meas.pdf

3. http://www.cdc.gov/vaccines/pubs/surv-manual/chpt07-measles.htm

4. http://www.who.int/mediacentre/factsheets/fs286/en/

5. http://www.who.int/vaccines-documents/GlobalSummary/GlobalSummary.pdf

6. http://www.immunize.org/catg.d/p2065.pdf (autism)

Measles At A Glance

Measles is a potentially serious disease.
Measles is due to a virus that is easily spread.
Measles can be complicated by ear infections, pneumonia, or encephalitis.
Measles infection of the brain (encephalitis) can cause convulsions, mental retardation, and even death.
Measles in pregnant women can cause miscarriages or premature delivery.
Measles can be prevented through vaccination.
Each person not immunized against measles is at risk for measles and puts others at risk.

REFERENCES:

American Academy of Pediatrics. "Measles." Red Book: 2006 Report of the Committee on Infectious Diseases, 28th ed. Ed. Pickering, L.K. Elk Grove Village, IL: American Academy of Pediatrics, 2006.

Perry, R.T., and N.A. Halsey. "The Clinical Significance of Measles: A review." J Infect Dis 189 (2004): S4–16.

United States. Centers for Disease Control and Prevention. "Measles." Manual for the Surveillance of Vaccine-Preventable Diseases, 4th ed. 2008. <http://www.cdc.gov/vaccines/pubs/surv-manual/chpt07-measles.htm>.

United States. Centers for Disease Control and Prevention. "Measles, Mumps, and Rubella -- Vaccine Use and Strategies for Elimination of Measles, Rubella, and Congenital Rubella Syndrome and Control of Mumps: Recommendations of the Advisory Committee on Immunization Practices (ACIP)." MMWR 47 (No. RR-8) 1998: 1–57.

United States. Centers for Disease Control and Prevention. "Notes from the Field: Measles Transmission Associated With International Air Travel -- Massachusetts and New York, July -- August 2010." MMWR 59.33 Aug. 2010: 1073.

United States. Centers for Disease Control and Prevention. "Use of Combination Measles, Mumps, Rubella, and Varicella Vaccine: Recommendations of the Advisory Committee on Immunization Practices (ACIP)." MMWR 59(RR03) 2010: 1-12.

World Health Organization. "Fifty-Sixth World Health Assembly. Agenda item 14.7. Reducing Global Measles Mortality." Geneva: World Health Organization, 2003. <http://www.who.int/gb/ebwha/pdf_files/WHA56/ea56r20.pdf>.

2010-12-02T04:07:00.000-08:00

What is cholera?

Cholera is an acute, diarrheal illness caused by infection of the intestine with the bacterium Vibrio cholerae. An estimated 3-5 million cases and over 100,000 deaths occur each year around the world. The infection is often mild or without symptoms, but can sometimes be severe. Approximately one in 20 (5%) infected persons will have severe disease characterized by profuse watery diarrhea, vomiting, and leg cramps. In these people, rapid loss of body fluids leads to dehydration and shock. Without treatment, death can occur within hours.

Where is cholera found?

The cholera bacterium is usually found in water or food sources that have been contaminated by feces (poop) from a person infected with cholera. Cholera is most likely to be found and spread in places with inadequate water treatment, poor sanitation, and inadequate hygiene.

The cholera bacterium may also live in the environment in brackish rivers and coastal waters. Shellfish eaten raw have been a source of cholera, and a few persons in the United States have contracted cholera after eating raw or undercooked shellfish from the Gulf of Mexico.

How does a person get cholera?

A person can get cholera by drinking water or eating food contaminated with the cholera bacterium. In an epidemic, the source of the contamination is usually the feces of an infected person that contaminates water and/or food. The disease can spread rapidly in areas with inadequate treatment of sewage and drinking water. The disease is not likely to spread directly from one person to another; therefore, casual contact with an infected person is not a risk for becoming ill.

What are the symptoms of cholera?

Cholera infection is often mild or without symptoms, but can sometimes be severe. Approximately one in 20 (5%) infected persons will have severe disease characterized by profuse watery diarrhea, vomiting, and leg cramps. In these people, rapid loss of body fluids leads to dehydration and shock. Without treatment, death can occur within hours.

How long after infection do the symptoms appear?

It can take anywhere from a few hours to 5 days for symptoms to appear after infection. Symptoms typically appear in 2-3 days.

Who is most likely to get cholera?

Individuals living in places with inadequate water treatment, poor sanitation, and inadequate hygiene are at a greater risk for cholera.

What should I do if I think I have cholera?

If you think you may have cholera, seek medical attention immediately. Dehydration can be rapid so fluid replacement is essential.

How is cholera diagnosed?

To test for cholera, doctors must take a stool sample or a rectal swab and send it to a laboratory to look for the cholera bacterium.

What is the treatment for cholera?

Cholera can be simply and successfully treated by immediate replacement of the fluid and salts lost through diarrhea. Patients can be treated with oral rehydration solution, a prepackaged mixture of sugar and salts to be mixed with water and drunk in large amounts. This solution is used throughout the world to treat diarrhea. Severe cases also require intravenous fluid replacement. With prompt rehydration, fewer than 1% of cholera patients die.

Antibiotics shorten the course and diminish the severity of the illness, but they are not as important as receiving rehydration. Persons who develop severe diarrhea and vomiting in countries where cholera occurs should seek medical attention promptly.

Should I be worried about getting cholera from others?

The disease is not likely to spread directly from one person to another; therefore, casual contact with an infected person is not a risk for becoming ill.

How can I avoid getting cholera?

The risk for cholera is very low for people visiting areas with epidemic cholera. When simple precautions are observed, contracting the disease is unlikely.

All people (visitors or residents) in areas where cholera is occurring or has occurred should observe the following recommendations:

Drink only bottled, boiled, or chemically treated water and bottled or canned carbonated beverages. When using bottled drinks, make sure that the seal has not been broken.

To disinfect your own water: boil for 1 minute or filter the water and add 2 drops of household bleach or ½ an iodine tablet per liter of water.

Avoid tap water, fountain drinks, and ice cubes.

Wash your hands often with soap and clean water.

If no water and soap are available, use an alcohol-based hand cleaner (with at least 60% alcohol).

Clean your hands especially before you eat or prepare food and after using the bathroom.

Use bottled, boiled, or chemically treated water to wash dishes, brush your teeth, wash and prepare food, or make ice.

Eat foods that are packaged or that are freshly cooked and served hot.

Do not eat raw and undercooked meats and seafood or unpeeled fruits and vegetables.

Dispose of feces in a sanitary manner to prevent contamination of water and food sources

Is a vaccine available to prevent cholera?

Currently, there are two oral cholera vaccines available, Dukoral (manufactured by SBL Vaccines) which is World Health Organization (WHO) prequalified and licensed in over 60 countries, and ShanChol (manufactured by Shantha Biotec in India), which is licensed in India and is pending WHO prequalification. Because the vaccine is a two dose vaccine, multiple weeks can elapse before persons receiving the vaccine are protected. Therefore, vaccination should not replace standard prevention and control measures. In addition, CDC does not recommend cholera vaccines for most travelers, nor is the vaccine available in the United States. This is because the available vaccines offer incomplete protection for a relatively short period of time.

Further information about Dukoral can be obtained from the manufacturers:

Dukoral®
SBL Vaccin AB,
SE-105 21 Stockholm, Sweden
telephone +46-8-7351000,
e-mail: info@sblvaccines.se
website: www.sblvaccines.se

Dengue Fever

2010-11-27T01:33:00.000-08:00

What is dengue fever?

Dengue fever is a disease caused by a family of viruses that are transmitted by mosquitoes. It is an acute illness of sudden onset that usually follows a benign course with symptoms such as headache, fever, exhaustion, severe muscle and joint pain, swollen glands (lymphadenopathy), and rash. The presence (the "dengue triad") of fever, rash, and headache (and other pains) is particularly characteristic of dengue. Other signs of dengue fever include bleeding gums, severe pain behind the eyes, and red palms and soles.
Dengue (pronounced DENG-gay) strikes people with low levels of immunity. Because it is caused by one of four serotypes of virus, it is possible to get dengue fever multiple times. However, an attack of dengue produces immunity for a lifetime to that particular serotype to which the patient was exposed.
Dengue goes by other names, including "breakbone" or "dandy fever." Victims of dengue often have contortions due to the intense joint and muscle pain, hence the name breakbone fever. Slaves in the West Indies who contracted dengue were said to have dandy fever because of their postures and gait.

Dengue hemorrhagic fever is a more severe form of the viral illness. Manifestations include headache, fever, rash, and evidence of hemorrhage in the body. Petechiae (small red or purple blisters under the skin), bleeding in the nose or gums, black stools, or easy bruising are all possible signs of hemorrhage. This form of dengue fever can be life-threatening and can progress to the most severe form of the illness, dengue shock syndrome.

What areas are at high risk for contracting dengue fever?

Dengue is prevalent throughout the tropics and subtropics. Outbreaks have occurred recently in the Caribbean, including Puerto Rico, the U.S. Virgin Islands, Cuba, and Central America. Cases have also been imported via tourists returning from areas with widespread dengue, including Tahiti, Singapore, the South Pacific, Southeast Asia, the West Indies, India, and the Middle East (similar in distribution to the areas of the world that harbor malaria and yellow fever). Dengue is now the leading cause of acute febrile illness in U.S. travelers returning from the Caribbean, South America, and Asia.

A 2009 outbreak of dengue fever in Key West, Fla., showed that three patients who did not travel outside of the U.S. contracted the virus. Subsequent testing of the population of Key West has shown that up to 55 of the people living in the area have antibodies to dengue. As of July 17, 2010, 17 individuals have been identified that acquired dengue in Key West in 2010.

Dengue fever is common, and statistics show it may be increasing in Southeast Asia. Thailand, Vietnam, Singapore, and Malaysia have all reported an increase in cases. According to the U.S. Centers for Disease Control and Prevention (CDC), there are an estimated 100 million cases of dengue fever with several hundred thousand cases of dengue hemorrhagic fever requiring hospitalization each year. Nearly 40% of the world's population lives in an area endemic with dengue.

How is dengue fever contracted?

The virus is contracted from the bite of a striped Aedes aegypti mosquito that has previously bitten an infected person. The mosquito flourishes during rainy seasons but can breed in water-filled flower pots, plastic bags, and cans year-round. One mosquito bite can inflict the disease.

The virus is not contagious and cannot be spread directly from person to person. There must be a person-to-mosquito-to-another-person pathway.

What are dengue fever symptoms and signs?

After being bitten by a mosquito carrying the virus, the incubation period ranges from three to 15 (usually five to eight) days before the signs and symptoms of dengue appear. Dengue starts with chills, headache, pain upon moving the eyes, and low backache. Painful aching in the legs and joints occurs during the first hours of illness. The temperature rises quickly as high as 104 F (40 C), with relative low heart rate (bradycardia) and low blood pressure (hypotension). The eyes become reddened. A flushing or pale pink rash comes over the face and then disappears. The glands (lymph nodes) in the neck and groin are often swollen.

Fever and other signs of dengue last for two to four days, followed by a rapid drop in body temperature (defervescence) with profuse sweating. This precedes a period with normal temperature and a sense of well-being that lasts about a day. A second rapid rise in temperature follows. A characteristic rash appears along with the fever and spreads from the extremities to cover the entire body except the face. The palms and soles may be bright red and swollen.

What is the treatment for dengue fever?

Because dengue fever is caused by a virus, there is no specific medicine or antibiotic to treat it. For typical dengue, the treatment is purely concerned with relief of the symptoms (symptomatic). Rest and fluid intake for adequate hydration is important. Aspirin and nonsteroidal anti-inflammatory drugs should only be taken under a doctor's supervision because of the possibility of worsening hemorrhagic complications. Acetaminophen (Tylenol) and codeine may be given for severe headache and for the joint and muscle pain (myalgia).

What is the prognosis for typical dengue fever?

Typical dengue is fatal in less than 1% of cases. The acute phase of the illness with fever and myalgias lasts about one to two weeks. Convalescence is accompanied by a feeling of weakness (asthenia), and full recovery often takes several weeks.

What is dengue hemorrhagic fever?

Dengue hemorrhagic fever (DHF) is a specific syndrome that tends to affect children under 10 years of age. It causes abdominal pain, hemorrhage (bleeding), and circulatory collapse (shock). DHF is also called Philippine, Thai, or Southeast Asian hemorrhagic fever and dengue shock syndrome.
DHF starts abruptly with high continuous fever and headache. There are respiratory and intestinal symptoms with sore throat, cough, nausea, vomiting, and abdominal pain. Shock occurs two to six days after the start of symptoms with sudden collapse, cool, clammy extremities (the trunk is often warm), weak pulse, and blueness around the mouth (circumoral cyanosis).
In DHF, there is bleeding with easy bruising, blood spots in the skin (petechiae), spitting up blood (hematemesis), blood in the stool (melena), bleeding gums, and nosebleeds (epistaxis). Pneumonia is common, and inflammation of the heart (myocarditis) may be present.
Patients with DHF must be monitored closely for the first few days since shock may occur or recur precipitously (dengue shock syndrome). Cyanotic (bluish) patients are given oxygen. Vascular collapse (shock) requires immediate fluid replacement. Blood transfusions may be needed to control bleeding.

The mortality (death) rate with DHF is significant. It ranges from 6%-30%. Most deaths occur in children. Infants under a year of age are especially at risk of dying from DHF.

How can dengue fever be prevented?

The transmission of the virus to mosquitoes must be interrupted to prevent the illness. To this end, patients are kept under mosquito netting until the second bout of fever is over and they are no longer contagious.
The prevention of dengue requires control or eradication of the mosquitoes carrying the virus that causes dengue. In nations plagued by dengue fever, people are urged to empty stagnant water from old tires, trash cans, and flower pots. Governmental initiatives to decrease mosquitoes also help to keep the disease in check but have been poorly effective.
To prevent mosquito bites, wear long pants and long sleeves. For personal protection, use mosquito repellant sprays that contain DEET when visiting places where dengue is endemic. Limiting exposure to mosquitoes by avoiding standing water and staying indoors two hours after sunrise and before sunset will help. The Aedes aegypti mosquito is a daytime biter with peak periods of biting around sunrise and sunset. It may bite at any time of the day and is often hidden inside homes or other dwellings, especially in urban areas.
There is currently no vaccine available for dengue fever. There is a vaccine undergoing clinical trials, but it is too early to tell if it will be safe or effective. Early results of clinical trials show that a vaccine may be available by 2012.

Dengue Fever At A Glance

Dengue fever is a disease caused by a family of viruses that are transmitted by mosquitoes.
Symptoms such as headache, fever, exhaustion, severe joint and muscle pain, swollen glands (lymphadenopathy), and rash. The presence (the "dengue triad") of fever, rash, and headache (and other pains) is particularly characteristic of dengue fever.
Dengue is prevalent throughout the tropics and subtropics. Outbreaks have occurred recently in the Caribbean, including Puerto Rico, the U.S. Virgin Islands, Cuba, and Central America.
Because dengue fever is caused by a virus, there is no specific medicine or antibiotic to treat it. For typical dengue fever, the treatment is purely concerned with relief of the symptoms (symptomatic).
The acute phase of the illness with fever and myalgias lasts about one to two weeks.
Dengue hemorrhagic fever (DHF) is a specific syndrome that tends to affect children under 10 years of age. It causes abdominal pain, hemorrhage (bleeding), and circulatory collapse (shock).
The prevention of dengue fever requires control or eradication of the mosquitoes carrying the virus that causes dengue.
There is currently no vaccine available for dengue fever.

Hepatitis C part 2

2010-11-27T01:20:00.000-08:00

What is the role of a liver biopsy in the management of chronic hepatitis C?

Blood tests can tell the clinician whether HCV is present but cannot tell the level of liver damage that has occurred. Liver biopsy allows the clinician to determine how much inflammation and scarring is present in a small sample of liver tissue. Liver biopsy may be recommended when the clinician is uncertain about whether to begin treatment or wishes to monitor the response within the liver to therapy.

Who should receive antiviral therapy for hepatitis C virus?

Patients at risk for cirrhosis should be considered for treatment of HCV. According to a consensus statement from the National Institutes of Health (NIH) these include persons with:

HCV infection and persistent elevation of ALT (alanine aminotransferase, a liver enzyme in the blood)
High levels of HCV RNA in the blood
HCV infection and evidence of fibrosis (scarring) on liver biopsy
HCV infection and evidence of at least moderate inflammation and liver cell injury (necrosis) on liver biopsy

These are general guidelines. Patients and providers may decide that treatment is needed for other reasons. For example, patients with HIV have a more rapid course of liver injury and may need treatment at an earlier stage. Newer therapies may be offered to selected patients in research settings.

Individuals who should not be treated with antiviral therapy include those who are unable to comply with the treatment schedule, should not take the specific medications (for example, allergy), and have reversible serious untreated conditions such as unstable heart disease, uncontrolled high blood pressure, or untreated major depression.

Patients with unstable (decompensated) cirrhosis are at high risk for complications for treatment and usually do not receive medical treatment, except in research settings. Fundamentally, the decision regarding antiviral therapy in chronic HCV infection should be tailored to the individual patient with careful consideration of the risks and benefits.

All patients with HCV should be vaccinated against hepatitis B and hepatitis A. They also should be counseled on measures to prevent the spread of HCV and eliminating alcohol use. Finally, risk behaviors for HCV overlap with those of HIV, and all patients with HCV should be tested for HIV.

What are the different patterns of response to antiviral treatment?

Treatment responses are mainly defined by results of the HCV RNA testing. Four patterns of response to antiviral treatment have been described:

1. sustained virologic response,

2. relapse,

3. partial response, and

4. non-response.

Sustained virologic response

The optimal response is a sustained virologic response (SVR), defined as the absence of detectable HCV RNA in serum using a sensitive test at the end of the treatment and six months later. Most of these individuals will remain in remission (no signs of the disease) indefinitely, with no detectable hepatitis C virus RNA in the blood or liver. Moreover, follow-up biopsies show a marked reduction in inflammation and there even can be regression of scarring. Longer follow-up of these patients is necessary, however, to evaluate definitively whether sustained responders will avoid the complications of cirrhosis and live longer.

Relapse

Relapsers are patients who initially eliminate the RNA from their blood but then develop detectable RNA again shortly after discontinuing therapy. The RNA becomes detectable again within six months and usually within the first three months of stopping treatment.

Partial responders

Patients whose HCV RNA levels decline but never become undetectable are referred to as partial responders.

No response

Patients who have sustained levels of detectable HCV RNA during therapy are known as non-responders. Patients in whom HCV RNA becomes undetectable during the early period of treatment but reappears before the end of therapy, should probably likewise be considered non-responders. This reappearance of HCV RNA during therapy is referred to as a 'break through' of HCV.

What are the goals of therapy for hepatitis C virus?

The ultimate goals of antiviral therapy are to eliminate HCV, improve or normalize the liver tests and histology (microscopic appearance), prevent progression to cirrhosis and liver cancer, prolong survival, and improve the quality of life.

As already indicated, only a sustained virologic response provides the possibility of achieving all of the ultimate goals, since most patients who have an SVR will remain in remission indefinitely. The rest of the patients (non-responders, partial responders and relapsers) may show improvement in blood tests with or without relief of symptoms.

What are the therapy options for previously untreated patients with chronic hepatitis C?

For previously untreated patients without reasons to be excluded from treatment, the optimal treatment is combined treatment with pegylated interferon and ribavirin (Rebetol, Copegus). Patients who have reasons not to receive ribavirin may be treated solely with pegylated interferon. Older preparations of interferon are less effective and less commonly used.

Pegylated interferon

Interferons are a family of naturally occurring proteins that are produced by the body to fight viral infections. To produce pegylated interferon, the interferon is processed by attaching ethylene glycol to it. This process is called pegylation and it slows the elimination of interferon from the body so that its effects are more prolonged. There are currently two types of pegylated interferon: pegylated interferon alpha 2b (Peg-Intron A) and pegylated interferon alpha 2a (Pegasys). Both pegylated interferon alpha 2b and 2a; are given as a subcutaneous injection once a week.

Optimally, pegylated interferon therapy should be combined with ribavirin. In persons who cannot take ribavirin, monotherapy with pegylated interferon may be used. Monotherapy has been shown to achieve sustained virologic response rates of 23% to 25% in patients.

Ribavirin

The antiviral agent, ribavirin (Rebetol, Copegus), is a nucleoside analogue that is taken by mouth. Nucleoside analogues are man-made molecules that closely resemble the biochemical units that make up genetic material (RNA and DNA). Ribavirin works by fooling the virus into using it instead of the normal building blocks, thereby slowing viral reproduction. Ribavirin has not worked well when used alone for hepatitis C.

Combined pegylated interferon and ribavirin

Combined therapy with both pegylated interferon and ribavirin produces a sustained virologic response in 28% to 50% of patients with genotype 1.
For unknown reasons, response rates are lower in African American persons and higher in Caucasians.
In patients with genotype 2, sustained response rates are higher (76% to 82%).
The duration of therapy depends on the genotype of the HCV.
Hence the recommended duration of treatment for HCV genotype 2 and 3 is 24 weeks and for genotype 1 is 48 weeks.
Sustained virologic response usually is accompanied by a return to normal serum ALT levels and improvement in inflammation within the liver.

Combination therapy is associated with more side effects than monotherapy (see below). In research studies, up to 20% of patients receiving combination therapy required a reduction in the doses or discontinuation of therapy because of the side effects. Nevertheless, combination therapy represents significant progress in the treatment of chronic HCV and is the current standard of care.

Some patients treated successfully with combination therapy still have detectable virus after 12 weeks of treatment but go on to have a sustained response. Therefore, patients on combination therapy should have hepatitis C virus RNA measured at 24 weeks of therapy. In those who are still positive for the virus at that time, consideration is given to stopping treatment, since the chance of sustained response is small.

How are relapses and nonresponders treated?

The optimal treatment for nonresponders and relapsers is not well established.
A minority of nonresponders (6% to 12%) will respond to a second course of pegylated interferon and ribavirin.
Patients initially treated with older interferon alpha monotherapy can be considered for the therapy of either pegylated interferon alpha monotherapy or pegylated interferon alpha plus ribavirin therapy.
Newer preparations of interferon such as 'consensus interferon' and albumin interferon are being studied and show promise in persons who did not respond to combination therapy.

Despite the failure to achieve sustained virologic response, treatment may slow the progression of HCV to cirrhosis, although this has not been shown for certain.

Should individuals with acute hepatitis C be treated?

When people first acquire HCV, the infection is said to be 'acute'. There is no standard approach to treatment for acute HCV. Most patients with acute HCV do not have symptoms, so they are not recognized as being infected. However, some have low-grade fever, fatigue or other symptoms that lead to an early diagnosis. Others who become infected have a known exposure to an infected source, such as a needlestick injury, and are monitored closely. Treatment decisions should be made on a case-by-case basis. However many experts prefer to hold treatment for several months to see whether the patient eliminates the virus without treatment.

What are the side effects of treatment for hepatitis C virus?

Flu-like symptoms, hair thinning and depression are common side effects of interferon or pegylated interferon. Depression may be serious and is common enough that patients should be monitored for this side effect.

Interferons may cause transient bone marrow suppression resulting in reduced white blood cell counts and hemoglobin. Reductions in white blood cell counts may cause increased susceptibility to infection. Death rarely occurs as a result of therapy, but may occur from progressive liver failure in patients with advanced cirrhosis.

Certain side effects are attributed to the addition of ribavirin to interferon, including nausea, cough, shortness of breath, rash, itching, insomnia, and loss of appetite.

Ribavirin also causes anemia due to the destruction of red blood cells (hemolysis). This anemia is usually mild but can become clinically significant. Ribavirin particularly may cause destruction of red blood cells (hemolysis) in people with kidney failure. Anemia improves with a reduction in the dose of ribavirin.

Ribavirin also accumulates in the testicles and ovaries and causes birth defects in animals. Although no birth defects have been reported in humans as yet, both men and women should use contraceptive measures to avoid pregnancy during and for at least six months after ribavirin treatment.

What about liver transplantation for hepatitis C?

HCV is the leading reason for liver transplantation in the U.S., accounting for 40% to 45% of transplants. HCV routinely recurs after transplantation and infects the new liver. Approximately 25% of these patients with recurrent hepatitis will develop cirrhosis within five years of transplantation. Despite these findings of recurrence, the five-year survival rate for patients with HCV is comparable to that of patients who are transplanted for other types of liver disease.

Treatment for recurrent hepatitis is not a simple issue. Interferon is an immune modulator (modifier) that may promote rejection of the transplanted liver. Furthermore, interferon may not be well tolerated by patients who just underwent transplantation and are taking many different kinds of medications.

What is the current research and what is in the future for hepatitis C?

As our awareness of HCV infection increases, more and more patients are being diagnosed with this condition. Current research includes diagnosis, natural history, treatment, and vaccine development.

Diagnosis: More accurate tests are being developed to detect even smaller amounts of the virus.
Natural history: There is much we do not know about the natural history of chronic HCV. Why do some people clear the virus spontaneously? What makes some people develop cirrhosis when others appear to have little liver damage? What predicts response to treatment or re-treatment?
Treatment: New formulations of interferon are being developed in the hopes of improving response rates. In addition, new agents are being tested in combination with pegylated interferon and ribavirin. Some of these agents, like telaprevir, inhibit protease enzymes that HCV needs in order to reproduce.
Vaccine development: Scientists have not been able to develop an effective vaccine against HCV. This is partly due to the ability of the HCV to change (mutate) and evade the body's immune responses.

Hepatitis C at A Glance

HCV is one of several viruses that cause hepatitis (inflammation of the liver).
Up to 85% of individuals who are initially (acutely) infected with HCV will fail to eliminate the virus and will become chronically infected.
HCV is spread most commonly through inadvertent exposure to infected blood. Intravenous drug abuse is the most common mode of transmission. The risk of acquiring HCV through sexual contact is low.
Generally, patients do not develop symptoms of chronic infection with HCV until they have extensive scarring of the liver (cirrhosis). Some individuals, however, may have fatigue and other non-specific symptoms in the absence of cirrhosis. A minority of patients with HCV have symptoms from organs outside of the liver.
In the U.S., Infection with HCV is the most common cause of chronic hepatitis and the most common reason for liver transplantation.
HCV is diagnosed by determining levels in the blood of antibodies to the virus and then confirmed with other tests for viral RNA. The amount of viral RNA in the blood (viral load) does not correlate with the severity of the disease but can be used to track the response to treatment.
A liver biopsy may be used to assess the amount of liver damage (liver cell injury and scarring), which can be important in planning treatment.
Considerable progress has been made in the treatment of HCV. Combined therapy with pegylated interferon and ribavirin is the standard treatment regimen.
Treatment results in reduced inflammation and scarring of the liver in most sustained responders and also occasionally (and to a much lesser extent) in those who relapse or do not respond.

Hepatitis C part 1

2010-11-27T01:10:00.000-08:00

What is hepatitis C?

Hepatitis C is an infection of the liver caused by the hepatitis C virus (HCV). It is difficult for the human immune system to eliminate the virus from the body, and infection with HCV usually becomes chronic. Over decades, chronic infection with HCV damages the liver and can cause liver failure in some people. In the U.S., the number of new cases of infection with HCV has declined over the last 10 years from a peak of some 200,000 annually to about 19,000 in 2006. When the virus first enters the body, there usually are no symptoms, so these numbers are estimates. Up to 85% of newly infected people fail to clear the virus and become chronically infected. In the U.S., more than three million people are chronically infected with HCV. Infection is most common among people who are 40 to 60 years of age, reflecting the high rates of infection in the 1970s and 1980s. There are 8,000 to 10,000 deaths each year in the U.S. related to HCV. HCV is the leading cause of liver transplantation in the U.S and is a risk factor for liver cancer.

What is the nature (biology) of the hepatitis C virus?

'Hepatitis' means inflammation of the liver. HCV is one of several viruses that can cause hepatitis. It is unrelated to the other common hepatitis viruses (for example, hepatitis A or hepatitis B). HCV is a member of the Flaviviridae family of viruses. Other members of this family of viruses include those that cause yellow fever and dengue.

Viruses belonging to this family all have ribonucleic acid (RNA) as their genetic material. All hepatitis C viruses are made up of an outer coat (envelope) and contain enzymes and proteins that allow the virus to reproduce within the cells of the body, in particular, the cells of the liver. Although this basic structure is common to all hepatitis C viruses, there are at least six distinctly different strains of the virus which have different genetic profiles (genotypes). In the U. S., genotype 1 is the most common form of HCV. Even within a single genotype there may be some variations (genotype 1a and 1b, for example). Genotyping is important to guide treatment because some viral genotypes respond better to therapy than others. The genetic diversity of HCV is one reason that it has been difficult to develop an effective vaccine since the vaccine must generate viral proteins from each genotype

How does liver damage occur in hepatitis C infection?

The presence of HCV in the liver triggers the human immune system, which leads to inflammation. Over time (usually decades), prolonged inflammation may cause scarring. Extensive scarring in the liver is called cirrhosis. When the liver becomes cirrhotic, the liver fails to perform its normal functions, (liver failure), and this leads to serious complications and even death. Cirrhotic livers also are more prone to become cancerous.

How is hepatitis C virus spread and how can transmission be prevented?

HCV is spread (transmitted) most efficiently through inadvertent exposure to infected blood.

The most common route of transmission is needles shared among users of illicit drugs.
Accidental needle-sticks in healthcare workers also have transmitted the virus.
The average risk of getting HCV from a stick with a contaminated needle is 1.8% (range 0% to 10%).
Prior to 1992, some people acquired the infection from transfusions of blood or blood products. Since 1992, all blood products are screened for HCV, and cases of HCV due to blood transfusion now are extremely rare.
HCV also can be passed from mother to unborn child. Approximately 4 of every 100 infants born to HCV-infected mothers become infected with the virus.
A small number of cases are transmitted through sexual intercourse. The risk of transmission of HCV from an infected individual to a non-infected spouse or partner without the use of condoms over a lifetime has been estimated to be 1% to 4%
Finally, there have been some outbreaks of HCV when instruments or sharp tool have been re-used without appropriate cleaning between patients.

Transmission of HCV can be prevented in several ways.

Programs have been aimed at avoiding needle sharing among drug addicts. Needle exchange programs and educational interventions have reduced high-risk behaviors. However, the population of drug addicts is a difficult population to reach, and rates of HCV remain high among addicts (30% of younger users).
Among healthcare workers, safe needle-usage techniques have been developed to reduce accidental needle-sticks. Newer syringes have self-capping needle systems that avoid the need to manually replace a cap after drawing blood and reduce the risk of needle-sticks.
There is no clear way to prevent transmission of the HCV from mother to child.
Persons with multiple sexual partners should use barrier precautions such as condoms to limit the risk of HCV as well as other sexually-transmitted diseases.
Monogamous couples should consider the low risk of transmission when deciding whether to use condoms during intercourse. Some couples may decide to use them and some may not.
Screening tests for blood products have almost eliminated the risk of transmission through transfusion, estimated by the CDC to be less than one in two million transfused blood products.
People with HCV should not share razors or toothbrushes with others.
It is critical that physicians and clinics follow manufacturer's directions for sterilizing/cleaning instruments and that disposable sharp instruments be discarded properly.

It is important to realize that HCV is not spread by casual contact. Thus, shaking hands, kissing, and hugging are not behaviors that increase the risk of transmission. There is no need to use special isolation procedures when dealing with infected patients.

What are the symptoms of hepatitis C infection?

About 75% of people have no symptoms when they first acquire HCV infection. The remaining 25% may complain of fatigue, loss of appetite, muscle aches or fever. Yellowing of the skin or eyes (jaundice) is rare at this early stage of infection.

Over time, the liver in people with chronic infection may begin to experience the effects of the persistent inflammation caused by the immune reaction to the virus. Blood tests may show elevated levels of liver enzymes, a sign of liver damage, which is often the first suggestion that the infection may be present. Patients may become easily fatigued or complain of nonspecific symptoms.

As cirrhosis develops, symptoms increase and may include :

weakness,
loss of appetite,
weight loss,
breast enlargement in men,
a rash on the palms,
difficulty with the clotting of blood, and
spider-like blood vessels on the skin.

In patients with advanced cirrhosis, the liver begins to fail. This is a life-threatening problem. Confusion and even coma (encephalopathy) may result from the inability of the liver to process certain toxic substances.

Increased pressure in the blood vessels of the liver (portal hypertension) may cause fluid to build up in the abdominal cavity (ascites) and result in engorged veins in the swallowing tube (esophageal varices) that tear easily and can bleed suddenly and massively. Portal hypertension also can cause kidney failure or an enlarged spleen resulting in a decrease of blood cells and the development of anemia, increased risk of infection and bleeding.

In advanced cirrhosis, liver failure causes decreased production of clotting factors. Patients with advanced cirrhosis often develop jaundice because the damaged liver is unable to eliminate a yellow compound, called bilirubin that is formed from the hemoglobin of old red blood cells.

What conditions outside the liver are associated with hepatitis C?

Most of the signs and symptoms of HCV relate to the liver. Less commonly, HCV causes conditions outside of the liver.

An example is when the body produces unusual antibodies called 'cryoglobulins'. These cryoglobulins cause inflammation of the arteries (vasculitis) which may damage the skin, joints, and kidneys. Patients with cryoglobulinemia may have joint pain, arthritis, a raised purple rash on the legs, generalized pain or swelling. In addition, these patients may develop Raynaud's phenomenon, in which the fingers and toes turn color (white, then purple, then red) and become painful at cold temperatures.
Two skin conditions, lichen planus and porphyria cutanea tarda, have been associated with chronic infection with HCV.
For reasons that are unclear, diabetes is three times more common among patients with chronic HCV infection than in the general population.
Low platelet counts may occur as a result of antibody-mediated platelet destruction.
HCV also is associated with B-cell lymphoma, a cancer of the lymph system.

What is the usual progression of chronic infection with the hepatitis C virus?

Our understanding of the natural progression (history) of HCV infection still is evolving.

Of 100 people infected with HCV, it is estimated that 75 to 85 will become chronically infected, 60 to 70 will develop liver disease, 5 to 20 will develop cirrhosis and 1 to 5 will die from complications of liver disease like cirrhosis or liver cancer.

Scientists are learning more about what causes some people to have milder problems and others to have serious complications. Drinking alcohol or acquiring other hepatitis viruses are risk factors for severe disease. Thus, persons who have chronic hepatitis C should avoid drinking and should be vaccinated against the other hepatitis viruses (A and B).

Liver cancer (hepatocellular carcinoma) is associated with cirrhosis due to chronic HCV infection. Some experts recommend screening patients with HCV and cirrhosis for liver cancer every six months with abdominal ultrasound and a blood test for alpha-fetoprotein (a marker for liver cancer). The effectiveness of this screening is unclear.

Who is at high risk and should be tested for hepatitis C infection?

Currently, screening for HCV is not recommended as part of a routine physical examination.

Rather, testing should be done in individuals at high risk for infection including current and past users of injectable drugs and persons exposed to infected blood or organs from infected persons.
Children born to chronically infected mothers should be tested to determine if they carry the virus.
Persons with abnormal levels of liver enzymes in the blood also should be tested.

These are not the only circumstances under which tests may be done. In general, testing is recommended when exposure to the virus is suspected.

What are the diagnostic tests for hepatitis C virus and how are they used to diagnose hepatitis C virus infection?

Several diagnostic tests currently are available for the diagnosis of HCV. They can be categorized according to the way the tests are used.

Screening tests

Screening tests are tests that are used to diagnose a condition or disease among individuals not known to have the disease. It is particularly useful for individuals who have risk factors for the condition or disease. The first step in screening for HCV is to test blood for the antibody to HCV using an enzyme-linked immunosorbent assay (ELISA). If the ELISA test is negative (does not find the antibody), the patient is assumed to be free of HCV. It takes several weeks (up to six months) for antibodies to develop after the initial infection with HCV, so this screening test may miss a few newly-infected individuals. However, in HCV physicians usually are looking for chronic infection so missing a few recently-infected individuals is not of much importance.

The ELISA test for HCV antibody is not perfect and may sometimes be positive in people who are not currently infected. Thus, if the ELISA test for HCV antibody is positive, additional testing is done to confirm the diagnosis with another type of test for the antibody. One such test is called the recombinant immunoblot assay (RIBA). It is read as either 'positive', 'negative' or 'indeterminate'. Indeterminate means that the result is unclear. Another option is to use molecular tests to measure the amount of HCV ribonucleic acid (RNA) in the blood.

Molecular tests for hepatitis C virus

As previously described, HCV is an RNA virus, meaning that it contains RNA. Several tests (assays) are available to measure the amount of HCV RNA in a person's blood. These tests are referred to as molecular tests because they examine the virus at the molecular level. A single negative test for RNA does not mean that there is no infection because the virus may appear in the blood intermittently or may exist in small amounts. Newer tests have helped by detecting smaller and smaller amounts of virus in the blood.

Testing for RNA is useful in determining whether or not a patient has circulating virus in the blood (viremia). Hence, it can be used to confirm that a positive ELISA truly reflects active hepatitis C virus infection.

RNA testing also should be done in individuals who may have been recently exposed to HCV. HCV RNA testing is more sensitive (that is, will detect more cases) than the conventional ELISA testing in this setting. The reason for this greater sensitivity is that it may take a person several weeks after exposure to HCV to develop the antibodies, whereas HCV RNA becomes detectable one to three weeks after exposure. Finally, HCV RNA testing may be helpful to assess a patient's virologic response to treatment at certain time points during antiviral therapy (see treatment of HCV below).

Hepatitis B part 2

2010-11-26T00:49:00.000-08:00

Self-Care at Home

The goals of self-care are to relieve symptoms and prevent worsening of the disease.

Drink plenty of fluids to prevent dehydration. Although, broth, sports drinks, gelatin, frozen ice treats (such as Popsicles), and fruit juices may be better because they also provide calories.

Ask your physician before taking any medications, even those that are over-the-counter. Some medications depend on the liver, and liver damage may impair the body's ability to metabolize these drugs. If you are on prescription medications, check with your physician to see if the doses should be adjusted or if the medication should be temporarily discontinued.

Avoid drinking alcohol until your health care practitioner allows it. Individuals with chronic HBV should avoid alcohol for the rest of their lives.

Try to eat a diet that provides adequate nutrition. Take it easy. It may take some time for your energy level to return to normal.

Avoid prolonged, vigorous exercise until symptoms start to improve.

Call your health care practitioner for advice if your condition worsens or new symptoms appear.

Avoid any activity that may spread the infection to other people (sexual intercourse, sharing needles, etc).

Medical Treatment

Acute hepatitis B infection

Acute hepatitis B infection is not treated with antiviral medications.

If the infected person is dehydrated from vomiting or diarrhea, a doctor may prescribe IV fluids to help them feel better. Medications may also be used to control these symptoms.

People with mild symptoms can be cared for at home.

Chronic hepatitis B infection

The degree of liver damage is related to the amount of active, replicating (multiplying) virus in the blood and liver. Regularly measuring the amount of HBV DNA ('viral load') in the blood gives your physician a good idea of how fast the virus is multiplying. The treatments now in use are classified as antiviral drugs, because they try to stop the virus from multiplying.

Antiviral agents, while the best therapy known for chronic hepatitis B, do not work in all individuals with the disease.

There are several antiviral agents for chronic hepatitis B approved by the U.S. Food and Drug Administration (FDA). New drugs are always being tested and treatment recommendations are subject to change.

Antiviral therapy is not appropriate for everyone with chronic HBV infection. It is reserved for people whose infection is most likely to progress to active hepatitis or cirrhosis.

Decisions to start medications for treatment of hepatitis B are made by the patient and health care practitioner, often in consultation with a specialist in diseases of the digestive system (gastroenterologist) or liver (hepatologist).

The decision to treat is guided by results of liver function tests, HBV DNA tests, and, frequently, liver biopsies after a complete history and physical examination.

Treatment is usually started when blood tests indicate that liver functions are deteriorating and the amount of replicating HBV is rising. Many people never reach this point. For those who do, the interval between diagnosis and starting treatment is quite variable.

Hepatitis B Medications

All of the following medications described that are used to treat chronic hepatitis B are antiviral medications. They reduce the ability of the virus to reproduce in the body and give the liver a chance to heal itself. These drugs are not a cure for hepatitis B, but they do reduce the damage caused by the virus. Although these medications are similar in some ways, they differ in other important ways. Talk to your health care practitioner about the best medication for you.

Pegylated interferon alfa-2b (Pegasys®)

Pegylated interferon is used alone or in combination with other medications.

Pegylated interferon slows the replication of the virus and boosts the body's immune system to fight the infection.

It works best in people who have relatively low levels of HBV DNA (low viral load).

Pegylated interferon usually is not given to people whose liver damage has progressed to cirrhosis, because it can make the liver damage worse.

Treatment is often given for 48 weeks, which is shorter than for other medications, but pegylated interferon requires regular shots (injections) while other medications are taken orally.

Pegylated interferon has unpleasant side effects in many people. The side effects are similar to having the flu. For many people, side effects are so severe that they cannot continue taking the medication.

Liver function tests and HBV DNA tests are used to check how well the treatment is working.

Interferon appears to stop the liver damage in up to 40% of people although relapse is possible.

Nucleoside/nucleotide analogues (NAs)

Nucleoside/nucleotide analogues (NAs) are compounds that mimic normal building blocks for DNA. When the virus tries to use the analogues, it is unable to make new viral particles. Examples of these agents include adefovir (Hepsera®), entecavir (Baraclude®), lamivudine (Epivir-HBV®, Heptovir®, Heptodin®), Telbivudine (Tyzeka®) and tenofovir (Viread®).

NAs reduce the amount of virus in the body. Between 20% and 90% of patients may have levels reduced so far that they become undetectable. Obviously, this is a broad range. The higher success rates are achieved in patients who do not have "hepatitis B e antigen" (HBeAg). HBeAg is detected by a blood test and indicates that the virus is actively multiplying.

Side effects are less common than with pegylated interferon. NAs have been associated with changes in body fat distribution, reduced blood cell counts, and increased levels of lactic acid in the blood. Rarely, NAs are associated with a severe flare of hepatitis that can be serious or fatal.

HBV may become resistant to NAs over time.

NAs do not cure the infection. Relapse is possible even in patients who have had a good response to treatment.

Surgery

There is no surgical therapy for hepatitis B.

If liver damage is so severe that the liver starts to fail, liver transplant may be recommended.

Liver transplant is a major process and surgery with an extended recovery period.

It also depends on the availability of a matching donor liver.

If liver transplant becomes a possibility for an individual, a health care practitioner will discuss the risks and benefits with them.

Hepatitis B Vaccine

There is a vaccine against the hepatitis B virus (Engerix-B, Recombivax HB). It is safe and works well to prevent the disease. A total of 3 doses of the vaccine are given over several months. Hepatitis B vaccine is also produced as a combination product which includes other common childhood vaccinations. This can reduce the number of shots that a child needs at a single visit.

The following groups should be vaccinated for hepatitis B:

All children younger than 19 years, including all newborns - especially those born to mothers who are infected with HBV

All health care and public safety workers who may be exposed to blood

People who have hemophilia or other blood clotting disorders and receive transfusions of human clotting factors

People who have end-stage renal disease including those who require hemodialysis for kidney disease

Travelers to countries where HBV infection is common. This includes most areas of Africa, Southeast Asia, China and Central Asia, Eastern Europe, the Middle East, the Pacific Islands, and the Amazon River basin of South America.

People who are in prison

People who live or work in residential facilities for developmentally disabled persons

People who inject illegal drugs

People with chronic liver disease such as hepatitis C

People who have multiple sex partners or have ever had a sexually transmitted disease

Men who have sex with men

Persons with HIV

People who have a sexual partner who is an HBV carrier.

Household contacts of persons who are carriers of HBV.

Anyone who wants to be vaccinated, regardless of risk factors.

Hepatitis B immune globulin (BayHep B, Nabi-HB) is given along with the hepatitis B vaccine to unvaccinated people who have been exposed to hepatitis B.

These include close contacts of people with HBV infection, health care workers who are exposed to HBV-contaminated blood, and infants born to mothers infected with HBV.

Giving the immune globulin and the vaccine together in these situations prevents transmission of the disease in 80% to 90% percent of cases.

Hepatitis B Prevention

In addition to the hepatitis B vaccine, other ways to protect yourself from HBV infection include:

If you are sexually active, practice safe sex. Correct use of latex condoms can help prevent transmission of HBV, but even when used correctly, condoms are not 100% effective at preventing transmission. Men who have sex with men should be vaccinated against both hepatitis A and hepatitis B.

If you inject drugs, don't share needles or other equipment.

Don't share anything (including grooming products) that might have blood on it, such as a razor, toothbrush, fingernail clippers, etc.

Think about the health risks if you are planning to get a tattoo or body piercing. You can become infected if the artist or person piercing you does not sterilize needles and equipment, use disposable gloves, or wash hands properly.

Health care workers should follow standard precautions and handle needles and sharps safely.

If you are pregnant or think you might be pregnant, tell your health care practitioner if you have any of the risk factors for HBV infection

Hepatitis B Prognosis

Some people rapidly improve after acute hepatitis B. Others have a more prolonged disease course with very slow improvement over several months, or with periods of improvement followed by worsening of symptoms. A small group of people (about 1% of infected people) suffer rapid progression of their illness during the acute stage and develop severe liver damage (fulminate hepatitis). This may occur over days to weeks and may be fatal.Other complications of HBV include development of a chronic HBV infection. People with chronic HBV infection are at further risk for liver damage (cirrhosis), liver cancer, liver failure, and death.

Hepatitis B part 1

2010-11-26T00:42:00.000-08:00

Hepatitis B Overview

Hepatitis B is an infectious hepatitis caused by the hepatitis B virus (HBV). This infection has two possible phases; 1) acute and 2) chronic.

Acute hepatitis B refers to newly acquired infections. Affected individuals notice symptoms approximately 1 to 4 months after exposure to the virus. In most people with acute hepatitis, symptoms resolve over weeks to months and they are cured of the infection. However, a small number of people develop a very severe, life-threatening form of acute hepatitis called fulminant hepatitis.
Chronic hepatitis B is an infection with HBV that lasts longer than 6 months. Once the infection becomes chronic, it may never go away completely.

Approximately 90% to 95% of infected adults are able to fight off the virus so their infection is cured. Only about 5% to 10% of adults infected with HBV go on to develop chronic infection. Children are at much higher risk for chronic infection. Up to 90% of infected young children will fail to clear the virus from their bodies and go on to develop chronic infection.

About two-thirds of people with chronic HBV infection are chronic carriers. These people do not develop symptoms, even though they harbor the virus and can transmit it to other people. The remaining one third develop "active" hepatitis, a disease of the liver that can be very serious.

The liver is an important organ that filters toxins out of the blood, stores energy for later use, helps with digestion, and makes substances that fight infections and control bleeding.

The liver has an incredible ability to heal itself, but long-term inflammation caused by HBV can result in permanent damage.

Scarring of the liver is called cirrhosis, a condition traditionally associated with alcoholism but one that is also caused by chronic active hepatitis B infection. When this occurs, the liver can no longer carry out its normal functions and may fail completely. The only treatment for liver failure is liver transplant.

Chronic hepatitis B also can lead to a type of liver cancer known as hepatocellular carcinoma.

Any of these conditions can be fatal. About 15% to 25% percent of people with chronic hepatitis B die of liver disease.

Hepatitis B is the most common serious liver infection in the world. Worldwide, about 350 million people are chronic carriers of HBV, of whom, more than 620,000 die from liver-related disease each year.

In the United States, hepatitis B is largely a disease of young adults aged 20-50 years. About 800,000 to 1.4 million Americans are chronic hepatitis B virus carriers, and the disease causes about 3, 000 deaths each year.

The good news is that infection with HBV is usually preventable because there is an effective vaccine. Use of the vaccine has resulted in an 82% decrease in the number of new infections reported in the United States each year.

Hepatitis B Transmission and Causes

The hepatitis B virus is known as a blood-borne virus because it is transmitted from one person to another via blood or fluids contaminated with blood. Another important route of transmission is from an infected mother to a newborn child, which occurs during or shortly after birth.

Direct contract with blood may occur through the use of dirty needles during illicit drug use, inadvertent needle sticks experienced by healthcare workers, or contact with blood through other means. Semen, which contain small amounts of blood, and saliva that is contaminated with blood also carry the virus.

The virus may be transmitted when these fluids come in contact with broken skin or a mucous membrane (in the mouth, genital organs, or rectum) of an uninfected person.

People who are at an increased risk of being infected with the hepatitis B virus include the following:

Men or women who have multiple sex partners, especially if they don't use a condom

Men who have sex with men

Men or women who have sex with a person infected with hepatitis B virus

People with other sexually transmitted diseases

People who inject drugs with shared needles

People who receive transfusions of blood or blood products

People who undergo dialysis for kidney disease

Institutionalized mentally handicapped people and their attendants, caregivers, and family members

Health care workers who are stuck with needles or other sharp instruments contaminated with infected blood

Infants born to infected mothers

In some cases, the source of transmission is never known.

You cannot get hepatitis B from the following activities:

Having someone sneeze or cough on you

Hugging someone

Handshaking a persons hand

Breastfeeding your child

Eating food or drinking water

Casual contact (such as an office or social setting)

Hepatitis B Symptoms

Half of all people infected with the hepatitis B virus have no symptoms and may never realize that they have been infected. Adults are more likely to develop symptoms than children. For those who do get sick, symptoms usually develop within 1 to 4 months after exposure to the virus. The initial symptoms are often similar to the flu.

Common symptoms of hepatitis B include:

Appetite loss

Feeling tired (fatigue)

Nausea and vomiting

Itching all over the body

Pain over the location of the liver (on the right side of the abdomen, under the lower rib cage)

Jaundice (a condition in which the skin and the whites of the eyes turn yellow in color)

Dark urine (the color of cola or tea)

Pale-colored stools (grayish or clay colored)

Many types of acute viral hepatitis such as hepatitis A and hepatitis C have symptoms that are indistinguishable from hepatitis B.

Fulminate hepatitis is a severe form of acute hepatitis that can be life-threatening if not treated right away. Fortunately, fulminate hepatitis is rare. The symptoms of fulminate hepatitis develop very suddenly and may include:

Mental disturbances such as confusion, lethargy, extreme sleepiness or hallucinations (hepatic encephalopathy)

Sudden collapse with fatigue

Jaundice

Swelling of the abdomen

Prolonged nausea and vomiting can cause dehydration. Individuals with dehydration may notice these symptoms:

Extreme weakness

Confusion or trouble concentrating

Headache

Lack of urination

Irritability

Symptoms of liver damage may include the following:

Fluid retention causing swelling of the belly (ascites) and sometimes the legs

Weight gain due to ascites

Persistent jaundice

Loss of appetite, weight loss, wasting

Vomiting with blood in the vomit

Bleeding from the nose, mouth, or rectum; or blood in the stool

Hepatic encephalopathy (excessive sleepiness, mental confusion, and in advanced stages, development of coma)

When to Seek Medical Care

Call your health care professional if you have any of the following:

Nausea and vomiting that does not go away in 1-2 days

The inability to keep down liquids

A high fever or fever that persists more than 2 days

Yellow skin or eyes

Dark-colored urine (like tea or cola)

Pain in the abdomen.

For severe symptoms including confusion or delirium go to a hospital emergency department.

You should also contact your health care practitioner if you think you may have been exposed to the hepatitis B virus.

If you have chronic hepatitis B infection and think you might be pregnant; or if you are pregnant and think you have been exposed to hepatitis B inform health care practitioner right away.

Hepatitis B Treatment

Acute hepatitis B usually resolves on its own and does not require medical treatment. If very severe, symptoms such as vomiting or diarrhea are present, the affected person may require treatment to restore fluids and electrolytes. There are no medications that can prevent acute hepatitis B from becoming chronic.
If a person has chronic hepatitis B, they should see their health care provider regularly

Hepatitis A

2010-11-25T07:29:00.000-08:00

Hepatitis A Overview

Hepatitis is a general term that means inflammation of the liver. Inflammation of the liver can result from infection, from exposure to alcohol, certain medications, chemicals, or poisons, or from a disorder of the immune system.

Hepatitis A refers to liver inflammation caused by infection with the hepatitis A virus (HAV). HAV is one of several viruses that can cause hepatitis and is one of the 3 most common hepatitis viruses in the United States. The other 2 are hepatitis B and hepatitis C.

Unlike hepatitis B and hepatitis C, hepatitis A does not cause chronic (ongoing, long-term) disease. Although the liver does become inflamed and swollen, it heals completely in most people without any long-term damage. Once you have had hepatitis A, you develop lifelong immunity and cannot get the disease again.

Because of the way it is spread, the hepatitis A virus tends to occur in epidemics and outbreaks. As many as 1 in 3 people in the United States have antibody to HAV, meaning they have been exposed to the virus, but most do not become ill. The number of cases of hepatitis A in the United States varies among different communities and has not been affected significantly by the introduction of the hepatitis A vaccine since the early 1990s.

Hepatitis A Causes

The hepatitis A virus is found in the stools (feces) of people with hepatitis A. It is transmitted when a person puts something in his or her mouth that has been contaminated with the feces of an affected person. This is referred to as fecal-oral transmission.

o If food or drinking water becomes contaminated with stool from an infected person (usually because of inadequate hand washing or poor sanitary conditions), the virus can quickly spread to anyone who drinks or swallows the contaminated food or water.

o The virus can also be spread by eating raw or undercooked shellfish collected from water that has been contaminated by sewage.

o The hepatitis A virus can be transmitted through blood transfusions, although this is extremely rare.

People who are infected can start spreading the infection about 1 week after their own exposure. People who do not have symptoms can still spread the virus. Infection with HAV is known to occur throughout the world.

o The risk of infection is greatest in developing countries with poor sanitation or poor personal hygiene standards.

o Infection rates are also higher in areas where direct fecal-oral transmission is likely to occur, such as daycare centers, prisons, and mental institutions.

People at increased risk for hepatitis A infection

o Household contacts of people infected with HAV

o Sexual partners of people infected with HAV

o International travelers, especially to developing countries

o Military personnel stationed abroad, especially in developing countries

o Men who have sex with other men

o Users of illegal drugs (injected or non-injected)

o People who may come into contact with HAV at work

Workers in professions such as health care, food preparation, and sewage and waste water management are not at greater risk of infection than the general public.

People who live or work in close quarters, such as dormitories, prisons, and residential facilities, or work in or attend daycare facilities are at increased risk only if strict personal hygiene measures are not observed.

Hepatitis A Symptoms

Many people with HAV infection have no symptoms at all. Sometimes symptoms are so mild that they go unnoticed. Older people are more likely to have symptoms than children. People who do not have symptoms can still spread the virus.

Symptoms of hepatitis A usually develop between 2 and 6 weeks after infection. The symptoms are usually not too severe and go away on their own, over time. The most common symptoms are as follows:

o Nausea

o Vomiting

o Diarrhea, especially in children

o Low-grade fever

o Loss of appetite

o Rash

o Tiredness, fatigue

o Jaundice - A yellow discoloration of the skin and the whites of the eyes

o Urine is dark brownish in color, like cola or strong tea.

o Pain in area of liver - On the right side of the abdomen, just under the rib cage

If the vomiting is severe, dehydration may occur. The symptoms of dehydration include the following:

o Feeling weak, tired, or "blah"

o Feeling confused or unable to concentrate

o Rapid heartbeat

o Headache

o Urinating less frequently than usual

o Irritability

Symptoms usually last less than two months, although they may last as long as nine months. About 15% of people infected with hepatitis A have symptoms that come and go for 6-9 months.

Hepatitis does not occur simply from being near someone who has the disease at work or at school.

When to Seek Medical Care

The health care provider should be called if any of the following symptoms occur:

Nausea and vomiting that does not improve within 1-2 days

Yellow skin or eyes

Dark colored urine

Pain in the belly (abdomen)

The following situations also warrant a call to the health care provider:

You have symptoms and think that you might have been exposed to someone with hepatitis.

You have other medical problems and think that you might have hepatitis.

You have had close contact with someone diagnosed with hepatitis.

If you cannot reach your health care provider, or if you have any of the following, go to the emergency department.

Vomiting and inability to keep down any liquids

Severe pain or high fever

Confusion, delirium, or difficulty awakening

Hepatitis A Diagnosis

Your health care provider will ask you questions about your illness. You will be asked about your symptoms and about any possible exposures to hepatitis.

If your health care provider determines that you may be at risk for contracting hepatitis, you will have blood drawn.

The blood will be tested to determine how well your liver is functioning.

A test will be done for antibody to hepatitis A. The test will show whether you have been exposed recently to HAV.

Your blood probably will be tested for the hepatitis B and hepatitis C viruses as well.

If you have had a large amount of vomiting or have not been able to take in liquids, your blood electrolytes may be out of balance. Your blood chemistry may be tested to check this

Hepatitis A Treatment

There are no specific medicines to cure infection with hepatitis A. Most people require no treatment except to relieve symptoms.

If you have been exposed to someone who is infected with HAV, there is a treatment that may prevent you from becoming infected. It is called immune globulin and is more likely to be effective when given within 2 weeks of exposure.

Self-Care at Home

The following measures can help you feel better while you are having symptoms.

Take it easy; curtail your normal activities and spend time resting at home.

Drink plenty of clear fluids to prevent dehydration.

Avoid medicines and substances that can cause harm to the liver such as acetaminophen (Tylenol) and preparations that contain acetaminophen.

Avoid alcoholic beverages, as these can worsen the effects of HAV on the liver.

Avoid prolonged, vigorous exercise until symptoms start to improve.

Call your health care provider if symptoms worsen or a new symptom appears.

Be very careful about personal hygiene to avoid fecal-oral transmission to other members of the household.

Medical Treatment

If you are dehydrated, your doctor may prescribe IV fluid to help you feel better.

If you are experiencing significant nausea and vomiting, you will receive medicines to control these symptoms.

People whose symptoms are well controlled can be cared for at home.

If dehydration or other symptoms are severe or if you are extremely confused or difficult to arouse, then you may need to stay in the hospital.

Next Steps

Follow-up

Follow the recommendations of your health care provider.

Take it easy; get plenty of rest.

Drink plenty of clear fluids.

Avoid alcoholic beverages.

Avoid medicines such as acetaminophen (Tylenol) that can be harmful to the liver.

Avoid prolonged or vigorous physical exercise until your symptoms improve.

Call your health care provider if symptoms worsen or a new symptom appears

Hepatitis A Prevention

If you have hepatitis A, strict personal hygiene and hand washing help prevent transmission of HAV to others.

Wash your hands thoroughly every time you use the bathroom, before touching or preparing food, and before touching others. Wash carefully with soap and warm water and dry thoroughly.

Contaminated surfaces should be cleaned with household bleach to kill the virus.

Heat food or water to 185°F or 85°C to kill the virus.

If you are not infected with HAV, you can protect yourself from becoming infected.

Wash your hands carefully with soap and warm water several times a day, including every time you use the bathroom, every time you change a diaper, and before preparing food.

Do not eat raw or undercooked seafood or shellfish such as oysters from areas of questionable sanitation (just about everywhere).

Travelers to developing countries should not drink untreated water or beverages with ice in them. Fruits and vegetables should not be eaten unless cooked or peeled.

There are vaccines that work to prevent infection with HAV.

The vaccines, Havrix and VAQTA, contain no live virus and are very safe. No serious adverse effects have been reported. Some people have some soreness at the injection site for a few days.

The vaccines are given in a series of 2 shots. The second is given 6-18 months after the first. The shots can be given at the same time as other vaccines.

Your protection starts about 2-4 weeks after the first shot. The second dose is necessary to ensure long-term protection.

The vaccines are thought to protect from infection for at least 20 years.

The vaccines must be given before exposure to the virus. They do not work after exposure.

Not everyone needs to have the hepatitis A vaccines. However, the vaccines are recommended for the following groups:

All children older than 2 years who live in communities where the number of HAV infections is unusually high or where there are periodic outbreaks of hepatitis A (The vaccines are not recommended for children younger than 2 years because they are not as effective.)

People who are likely to be exposed to HAV at work - The only group of workers shown to be at higher risk than the general population is people who work in research laboratories where HAV is stored and handled. Routine vaccination is not recommended for health care workers, food service workers, daycare personnel, and sewage and waste-water workers.

Travelers to developing countries (it must be given at least 4 weeks before travel)

Men who have sex with men

People who use illegal drugs - This group has higher-than-average rates of HAV infection.

People who are likely to become seriously ill if they are infected with HAV - This includes people with impaired immune systems or chronic liver disease.

People with blood-clotting disorders who receive clotting factors

If you have never had hepatitis A and are exposed to the virus, call your health care provider immediately. There is a treatment that may prevent you from becoming infected. It is called hepatitis B immune globulin (BayHep B, Nabi-HB).

Immune globulin is a preparation of antibodies that can fight the virus in the body.

It is given as a one-time shot (injection).

It must be given within 2 weeks after exposure for maximum protection.

Immune globulin can be safely given to children younger than 2 years.

Immune globulin can be given during pregnancy and breastfeeding.

Immune globulin can provide short-term protection against infection if given before exposure. This protection lasts no longer than 3 months.

If you have had hepatitis A confirmed by a blood test, you cannot get it again. You should continue to practice preventive measures, however, to prevent transmission of other infections.

Hepatitis A Prognosis

Hepatitis A symptoms are usually mild and go away on their own.

Rarely will you develop complications such as relapsing hepatitis or liver failure.

With relapsing hepatitis, symptoms improve, but then return.

Death from hepatitis A is rare.

The elderly, the very young, and people with advanced chronic liver diseases such as from hepatitis C are at greatest risk for complications from hepatitis A

Hepatitis

2010-11-25T07:09:00.000-08:00

Hepatitis (plural hepatitides) is an inflammation of the liver characterized by the presence of inflammatory cells in the tissue of the organ. The name is from the Greek hepar (ἧπαρ), the root being hepat- (ἡπατ-), meaning liver, and suffix -itis, meaning "inflammation". The condition can be self-limiting (healing on its own) or can progress to fibrosis (scarring) and cirrhosis.
Hepatitis may occur with limited or no symptoms, but often leads to jaundice, anorexia (poor appetite) and malaise. Hepatitis is acute when it lasts less than six months and chronic when it persists longer. A group of viruses known as the hepatitis viruses cause most cases of hepatitis worldwide, but it can also be due to toxins (notably alcohol, certain medications and plants), other infections and autoimmune diseases.

Signs and symptoms

Acute

Initial features are of nonspecific flu-like symptoms, common to almost all acute viral infections and may include malaise, muscle and joint aches, fever, nausea or vomiting, diarrhea, and headache. More specific symptoms, which can be present in acute hepatitis from any cause, are: profound loss of appetite, aversion to smoking among smokers, dark urine, yellowing of the eyes and skin (i.e., jaundice) and abdominal discomfort. Physical findings are usually minimal, apart from jaundice in a third and tender hepatomegaly (swelling of the liver) in about 10%. Some exhibit lymphadenopathy (enlarged lymph nodes, in 5%) or splenomegaly (enlargement of the spleen, in 5%).

Acute viral hepatitis is more likely to be asymptomatic in younger people. Symptomatic individuals may present after convalescent stage of 7 to 10 days, with the total illness lasting 2 to 6 weeks.

A small proportion of people with acute hepatitis progress to acute liver failure, in which the liver is unable to clear harmful substances from the circulation (leading to confusion and coma due to hepatic encephalopathy) and produce blood proteins (leading to peripheral edema and bleeding). This may become life-threatening and occasionally requires a liver transplant.

Chronic

Chronic hepatitis often leads nonspecific symptoms such as malaise, tiredness and weakness, and often leads to no symptoms at all. It is commonly identified on blood tests performed either for screening or to evaluate nonspecific symptoms. The occurrence of jaundice indicates advanced liver damage. On physical examination there may be enlargement of the liver.

Extensive damage and scarring of liver (i.e. cirrhosis) leads to weight loss, easy bruising and bleeding tendencies, peripheral edema (swelling of the legs) and accumulation of ascites (fluid in the abdominal cavity). Eventually, cirrhosis may lead to various complications: esophageal varices (enlarged veins in the wall of the esophagus that can cause life-threatening bleeding) hepatic encephalopathy (confusion and coma) and hepatorenal syndrome (kidney dysfunction).

Acne, abnormal menstruation, lung scarring, inflammation of the thyroid gland and kidneys may be present in women with autoimmune hepatitis.

Causes

Acute

Viral hepatitis:

Non viral infection

Alcohol
Toxins: Amanita toxin in mushrooms, carbon tetrachloride, asafetida
Drugs: Paracetamol, amoxycillin, antituberculosis medicines, minocycline and many others (see longer list below).
Ischemic hepatitis (circulatory insufficiency)
Pregnancy
Auto immune conditions, e.g., Systemic Lupus Erythematosus (SLE)
Metabolic diseases, e.g., Wilson's disease

Chronic

Viral hepatitis: Hepatitis B with or without hepatitis D, hepatitis C (neither hepatitis A nor hepatitis E causes chronic hepatitis)
Autoimmune

Autoimmune hepatitis

Alcohol
Drugs

Non-alcoholic steatohepatitis
Heredity

Primary biliary cirrhosis and primary sclerosing cholangitis occasionally mimic chronic hepatitis

Alcoholic hepatitis

Ethanol, mostly in alcoholic beverages, is a significant cause of hepatitis. Usually alcoholic hepatitis comes after a period of increased alcohol consumption. Alcoholic hepatitis is characterized by a variable constellation of symptoms, which may include feeling unwell, enlargement of the liver, development of fluid in the abdomen ascites, and modest elevation of liver blood tests. Alcoholic hepatitis can vary from mild with only liver test elevation to severe liver inflammation with development of jaundice, prolonged prothrombin time, and liver failure. Severe cases are characterized by either obtundation (dulled consciousness) or the combination of elevated bilirubin levels and prolonged prothrombin time; the mortality rate in both categories is 50% within 30 days of onset.

Alcoholic hepatitis is distinct from cirrhosis caused by long term alcohol consumption. Alcoholic hepatitis can occur in patients with chronic alcoholic liver disease and alcoholic cirrhosis. Alcoholic hepatitis by itself does not lead to cirrhosis, but cirrhosis is more common in patients with long term alcohol consumption. Patients who drink alcohol to excess are also more often than others found to have hepatitis C.^{[citation needed]} The combination of hepatitis C and alcohol consumption accelerates the development of cirrhosis.

Drug induced

A large number of drugs can cause hepatitis:

Agomelatine (antidepressant)
Allopurinol
Amitriptyline (antidepressant)
Amiodarone (antiarrhythmic)
Atomoxetine ^[8]
Azathioprine^[9]
Halothane (a specific type of anesthetic gas)
Hormonal contraceptives
Ibuprofen and indomethacin (NSAIDs)
Isoniazid (INH), rifampicin, and pyrazinamide (tuberculosis-specific antibiotics)
Ketoconazole (antifungal)
Loratadine (antihistamine)
Methotrexate (immune suppressant)
Methyldopa (antihypertensive)
Minocycline (tetracycline antibiotic)
Nifedipine (antihypertensive)
Nitrofurantoin (antibiotic)
Paracetamol (acetaminophen in the United States) can cause hepatitis when taken in an overdose. The severity of liver damage may be limited by prompt administration of acetylcysteine.
Phenytoin and valproic acid (antiepileptics)
Troglitazone (antidiabetic, withdrawn in 2000 for causing hepatitis)
Zidovudine (antiretroviral i.e., against HIV)
Some herbs and nutritional supplements

The clinical course of drug-induced hepatitis is quite variable, depending on the drug and the patient's tendency to react to the drug. For example, halothane hepatitis can range from mild to fatal as can INH-induced hepatitis. Hormonal contraception can cause structural changes in the liver. Amiodarone hepatitis can be untreatable since the long half life of the drug (up to 60 days) means that there is no effective way to stop exposure to the drug. Statins can cause elevations of liver function blood tests normally without indicating an underlying hepatitis. Lastly, human variability is such that any drug can be a cause of hepatitis.

Other toxins

Other Toxins can cause hepatitis:

Amatoxin-containing mushrooms, including the Death Cap (Amanita phalloides), the Destroying Angel (Amanita ocreata), and some species of Galerina. A portion of a single mushroom can be enough to be lethal (10 mg or less of α-amanitin).
White phosphorus, an industrial toxin and war chemical.
Carbon tetrachloride ("tetra", a dry cleaning agent), chloroform, and trichloroethylene, all chlorinated hydrocarbons, cause steatohepatitis (hepatitis with fatty liver).
Cylindrospermopsin, a toxin from the cyanobacterium Cylindrospermopsis raciborskii and other cyanobacteria.

Metabolic disorders

Some metabolic disorders cause different forms of hepatitis. Hemochromatosis (due to iron accumulation) and Wilson's disease (copper accumulation) can cause liver inflammation and necrosis.

Non-alcoholic steatohepatitis (NASH) is effectively a consequence of metabolic syndrome.

Obstructive

"Obstructive jaundice" is the term used to describe jaundice due to obstruction of the bile duct (by gallstones or external obstruction by cancer). If longstanding, it leads to destruction and inflammation of liver tissue.

Autoimmune

Anomalous presentation of human leukocyte antigen (HLA) class II on the surface of hepatocytes, possibly due to genetic predisposition or acute liver infection; causes a cell-mediated immune response against the body's own liver, resulting in autoimmune hepatitis.

Alpha 1-antitrypsin deficiency

In severe cases of alpha 1-antitrypsin deficiency (A1AD), the accumulated protein in the endoplasmic reticulum causes liver cell damage and inflammation.

Non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the occurrence of fatty liver in people who have no history of alcohol use. It is most commonly associated with obesity (80% of all obese people have fatty liver). It is more common in women. Severe NAFLD leads to inflammation, a state referred to as non-alcoholic steatohepatitis (NASH), which on biopsy of the liver resembles alcoholic hepatitis (with fat droplets and inflammatory cells, but usually no Mallory bodies).

The diagnosis depends on medical history, physical exam, blood tests, radiological imaging and sometimes a liver biopsy. The initial evaluation to identify the presence of fatty infiltration of the liver is medical imaging, including such ultrasound, computed tomography (CT), or magnetic resonance (MRI). However, imaging cannot readily identify inflammation in the liver. Therefore, the differentiation between steatosis and NASH often requires a liver biopsy. It can also be difficult to distinguish NASH from alcoholic hepatitis when the patient has a history of alcohol consumption. Sometimes in such cases a trial of abstinence from alcohol along with follow-up blood tests and a repeated liver biopsy are required.

NASH is becoming recognized as the most important cause of liver disease second only to hepatitis C in numbers of patients going on to cirrhosis.^{[citation needed]}

Ischemic hepatitis

Ischemic hepatitis is caused by decreased circulation to the liver cells. Usually this is due to decreased blood pressure (or shock), leading to the equivalent term "shock liver". Patients with ischemic hepatitis are usually very ill due to the underlying cause of shock. Rarely, ischemic hepatitis can be caused by local problems with the blood vessels that supply oxygen to the liver (such as thrombosis, or clotting of the hepatic artery which partially supplies blood to liver cells). Blood testing of a person with ischemic hepatitis will show very high levels of transaminase enzymes (AST and ALT), which may exceed 1000 U/L. The elevation in these blood tests is usually transient (lasting 7 to 10 days). It is rare that liver function will be affected by ischemic hepatitis.

References

1. ^ Online Etymology Dictionary

2. ^ Ryder S, Beckingham I (2001). "ABC of diseases of liver, pancreas, and biliary system: Acute hepatitis". BMJ 322 (7279): 151–153. doi:10.1136/bmj.322.7279.151. PMID 11159575.

3. ^ ^a ^b V.G. Bain and M. Ma, Acute Viral Hepatitis, Chapter 14, First principle of gastroenterology (an online text book)

4. ^ ^a ^b Chronic hepatitis at Merck Manual of Diagnosis and Therapy Home Edition

5. ^ Figure 7.12 (Some causes of acute parenchymal damage), Parveen, M.D. Kumar (Editor), Michael, M.d. Clark (Editor) (2005). Clinical Medicine: with STUDENT CONSULT Access. Philadelphia, PA: W.B. Saunders Company. ISBN 0-7020-2763-4.

6. ^ Scott Moses, MD, Acute Hepatitis causes, Family practice notebook.com

7. ^ "Hepatitis as a result of chemicals and drugs". HealthAtoZ. Archived from the original on 2006-06-23. http://web.archive.org/web/20060623141402/http://www.healthatoz.com/healthatoz/Atoz/dc/caz/infc/hepa/hepres.jsp. Retrieved 2006-07-01.

8. ^ Lim JR, Faught PR, Chalasani NP, Molleston JP (2006). "Severe liver injury after initiating therapy with atomoxetine in two children". J. Pediatr. 148 (6): 831–4. doi:10.1016/j.jpeds.2006.01.035. PMID 16769398.

9. ^ Bastida G, Nos P, Aguas M, Beltrán B, Rubín A, Dasí F, Ponce J (2005). "Incidence, risk factors and clinical course of thiopurine-induced liver injury in patients with inflammatory bowel disease". Aliment Pharmacol Ther 22 (9): 775–82. doi:10.1111/j.1365-2036.2005.02636.x. PMID 16225485.

10. ^ Nadir A, Reddy D, Van Thiel DH (2000). "Cascara sagrada-induced intrahepatic cholestasis causing portal hypertension: case report and review of herbal hepatotoxicity". Am. J. Gastroenterol. 95 (12): 3634–7. doi:10.1111/j.1572-0241.2000.03386.x. PMID 11151906.

Malaria and Its Symptoms

2010-10-18T11:49:00.000-07:00

Definitions and symptoms

As the malaria parasites enter the blood stream they infect and destroy red blood cells. Destruction of these essential cells leads to fever and flu-like symptoms, such as chills, headache, muscle aches, tiredness, nausea, vomiting and diarrhea. These initial symptoms are non-specific: in other words, they are self-reported symptoms that do not indicate a specific disease process.

Uncomplicated malaria (can be caused by all strains of Plasmodium)

Malaria is considered uncomplicated when symptoms are present but there are no clinical or laboratory signs to indicate severity or vital organ dysfunction.² The symptoms of uncomplicated malaria are non-specific and include fever.

Severe malaria (only caused by P. falciparum)

Infection with P. falciparum, if not promptly treated, can quickly progress to severe malaria. The main symptoms of severe malaria include: coma, severe breathing difficulties, low blood sugar, and low blood haemoglobin (severe anaemia). It is diagnosed on the basis of the presence P. falciparum parasites and one of the above symptoms with no other obvious cause. Children are particularly vulnerable since they have little or no immunity to the parasite. If untreated, severe malaria can lead to death.

Cerebral malaria (only caused by P. falciparum)

Malaria is classified as cerebral when it manifests with cerebral symptoms, such as coma.