• GRAM-NEGATIVE RODS
• NON-MOTILE
• NON-SPORE-FORMING
• CATALASE: POSITIVE
• OXIDASE: NEGATIVE
• FACULTATIVELY ANAEROBIC

Klebsiella will produce acid, which lowers the pH of the agar below 6.8 and results in the appearance of pink colonies.

Klebsiella and Enterobacter, produce mucoid colonies which appear very moist and sticky. This phenomenon happens because the organism is producing a capsule.

Klebsiella on MacConkey

• Segmented neutrophilic granulocyte during degradation, often seen as an artifact after prolonged sample storage (more than eight hours).

Granulocyte during degradation

Causal organisms:

• Trichophyton rubrum is the most common cause.
• Epidermophyton floccosum and T. mentagrophytes var.interdigitale are also seen.
• Not unusual condition often reduced in size via strolling barefoot
  on contaminated floors.
• Extensive sweating and occlusive sneakers predispose to
  the condition.
• Infection with the moulds Scytalidium dimidiatum (Hendersonulatoruloidea) and S. hyalinum is clinically indistinguishable.

Clinical manifestations:
3 types are recognized:

• acute or chronic interdigital infection: itching, peeling,
  maceration and fissuring of toe webs
• chronic hyperkeratotic (moccasin or dry type): high quality, white
  scaling restricted to heels, soles and lateral borders of toes
• vesicular (inflammatory) infection: vesicle formation on
  soles, instep and interdigital cleft. Secondary bacterial or yeast infection is also possible.

Diagnosis:

Microscopy

• Direct microscopy of pores and skin scrapings softened with KOH unearths
  branching hyphae without or with arthrospores.

Culture

• Isolation of the dermatophyte at 28°C permits identification.

Tinea pedis – Feet Dermatophyte infection

Image Source: tipfak.com

Clinical setting for DIC:

(i) Main trauma
(ii) Septicaemia (usually with acidosis)
(iii) Obstetric crises (placental abruption, eclampsia, retained lifeless foetus)
(iv) Malignancy (acute promyelocytic leukaemia)

Exams for DIC embody FBC (with blood film for fragments), platelet depend (as part of FBC), prothrombin time (PT), APTT, fibrinogen assay and D-dimers.

Pathogenesis of DIC (Disseminated intravascular coagulation)

• A high CK, or one that goes up from the first to the second or later samples, generally indicates that there has been some damage to the heart or other muscles. It can also indicate that your muscles have experienced heavy use. If your doctor suspects a heart attack and your CK is high, she will usually order a more specific test (troponin or CK-MB) to see if your heart is damaged.

CK-MB

• CK-MB is usually ordered, along with total CK, in persons with chest pain to determine whether the pain is due to a heart attack. It may also be ordered in a person with a high CK to determine whether damage is to the heart or other muscles.

• If the value of CK-MB is elevated and the ratio of CK–MB to total CK (relative index) is more than 2.5–3, it is likely that the heart was damaged. A high CK with a relative index below this value suggests that skeletal muscles were damaged.

Heart Attack – Cardiac Markers

• Cholesterol testing is recommended as a screening test to be done on all adults at least once every five years. It is frequently done in conjunction with a routine physical exam. It is usually ordered in combination with other tests including HDL, LDL, and triglycerides — often called a lipid profile.

• Cholesterol is tested at more frequent intervals (often several times per year) in patients who have been prescribed diet and/or drugs to lower their cholesterol. The test is used to track how well these measures are succeeding in lowering cholesterol to desired levels and in turn lowering the risk of developing heart disease.

Bad vs Good Cholesterol

• All sexually active females under 20 years of age (test at least once a year).
• Women ages 20 and older who have one or more risk factors (test annually). Risk factors include having new or multiple sex partners, having sex with someone who has other partners, and not using barrier contraceptives, such as condoms.
• All women with an infection of the cervix.
• All pregnant women.

A positive test indicates an active infection that requires treatment with a course of antibiotics.

Chlamydia Antigen Detection:

• The test is an immunoassay in the format of immuno-chromatographic strips (ICSs) encased within a plastic cassette. The test detects antigen using high-affinity antibodies fixed onto nitrocellulose strips. A is a solubilising buffer, which releases the chlamydia from the host cells on the swab. B is a reagent mixture, which contains the reagents necesssary to visualise the test result.

Rapid Chlamydia Antigen Detection Test

Sources:
Peeling et al. Nature Reviews Microbiology 4, S7–S19 (December 2006) | doi:10.1038/nrmicro1569

Calcium can be used as a diagnostic test if you go to your doctor with symptoms that suggest:

• kidney stones,
• bone disease, or
• neurologic (nerve-related) disorders.

Your doctor also may order a calcium test if:

• you have kidney disease, because low calcium is especially common in those with kidney failure;
• you have symptoms of too much calcium, such as fatigue, weakness, loss of appetite, nausea, vomiting, constipation, abdominal pain, urinary frequency, and increased thirst;
• you have symptoms of low calcium, such as cramps in your abdomen, muscle cramps, or tingling fingers; or
• you have other diseases that can be associated with abnormal blood calcium, such as thyroid disease, intestinal disease, cancer, or poor nutrition.

Your doctor may order an ionized calcium test if you have numbness around the mouth and in the hands and feet and muscle spasms in the same areas, which are symptoms of low levels of ionized calcium. If calcium levels fall slowly, however, many people have no symptoms at all.

You may need calcium monitoring as part of your regular laboratory tests if you have certain kinds of cancer (particularly breast, lung, head and neck, kidney, and multiple myeloma) or kidney disease or transplant. You may need to be monitored for calcium level also if it is clear that you have abnormal calcium levels or if you are receiving calcium or vitamin D

A normal calcium result with other normal lab results means that you have no problems with calcium metabolism (use by the body).

Because about half of the calcium in your blood is bound by albumin (a protein), these two tests are usually ordered together. Calcium values must be interpreted in combination with albumin to determine if the calcium concentration of serum is appropriate. As albumin levels rise, calcium rises as well, and vice versa.

A high calcium level is called hypercalcemia. You have too much calcium in your blood and will need treatment for the underlying condition. This usually is caused by:

• Hyperparathyroidism (increase in parathyroid gland function): This condition is usually caused by a benign (not cancerous) tumor on the parathyroid gland. This form of hypercalcemia is usually mild and can be present for many years before being noticed.
• Cancer: Cancer can cause hypercalcemia when it spreads to the bones, which releases calcium into the blood, or when cancer causes a hormone similar to PTH to increase calcium levels.

Other causes of hypercalcemia include:

• hyperthyroidism,
• sarcoidosis,
• tuberculosis,
• bone breaks combined with bed rest or not moving for a long periods of time,
• excess Vitamin D intake,
• kidney transplant, and high protein levels (for example, if a tourniquet is used for too long while blood is collected). In this case, free or ionized calcium remains normal.

High levels of ionized calcium occur with all the above, except high protein levels.

Low calcium levels, called hypocalcemia, mean that you do not have enough calcium in your blood or that you don’t have enough protein in your blood. The most common cause of low total calcium is low protein levels, especially low albumin. When low protein is the problem, the ionized calcium level remains normal.

Low calcium, known as hypocalcemia, is caused by many conditions:

• low protein levels,
• underactive parathyroid gland (hypoparathyroidism),
• decreased dietary intake of calcium,
• decreased levels of vitamin D,
• magnesium deficiency,
• too much phosphorus,
• acute inflammation of the pancreas,
• chronic renal failure,
• calcium ions becoming bound to protein (alkalosis),
• bone disease,
• malnutrition, and alcoholism.

Causes of low ionized calcium levels include all the above, except low protein levels.

Calcium Regulation

• A CEA test is ordered when the patient’s symptoms suggest the possibility of cancer. The CEA level is also tested before treatment in cancer patients, especially patients with GI cancers. CEA levels are monitored during therapy. It is also used to follow up patients after therapy.

• On initial testing, patients with smaller and early-stage tumors are likely to have low, if not normal, CEA levels, while patients with more advanced tumors, or tumors that have spread throughout the body, are likely to have initially high CEA levels. When CEA levels decrease to “normal” levels after therapy, it means that the CEA-producing tumor has been removed. A steadily rising CEA level is occasionally the first sign of tumor recurrence. When cancer spreads to other organs, CEA levels rise and may be present in other types of bodily fluids besides blood. For example, if CEA is detected in cerebrospinal fluid, this indicates a central nervous system metastasis.

• to help differentiate between cancer of the pancreas and bile ducts and other non-cancerous conditions, such as pancreatitis; 
• to monitor a patient’s response to pancreatic cancer treatment; and
• to watch for pancreatic cancer recurrence.

CA 19-9 can only be used as a marker if the cancer is producing elevated amounts of it; if CA 19-9 is not initially elevated, then it usually cannot be used later as a marker.

CA 19-9 may be ordered along with other tests, such as carcinoembryonic antigen (CEA), bilirubin, and/or a liver panel, when a patient has symptoms that may indicate pancreatic cancer, including abdominal pain, nausea, weight loss, and jaundice.

If CA 19-9 is initially elevated in pancreatic cancer, then it may be ordered several times during cancer treatment to monitor response and, on a regular basis following treatment, to help detect recurrence.

Low amounts of CA 19-9 can be detected in a certain percentage of healthy people, and many conditions that affect the liver or pancreas can cause temporary elevations.

Moderate to high levels are found in pancreatic cancer, other cancers, and in several other diseases and conditions. The highest levels of CA 19-9 are seen in excretory ductal pancreatic cancer — cancer that is found in the pancreas tissues that produce food-digesting enzymes and in the ducts that carry those enzymes into the small intestine. This tissue is where 95% of pancreatic cancers are found.

Serial measurements of CA 19-9 may be useful during and following treatment because rising or falling levels may give your doctor important information about whether the treatment is working, whether all of the cancer was removed successfully during surgery, and whether the cancer is likely returning.