Aldosterone test
Aldosterone test maesures the level of aldosterone hormone in the blood. Aldosterone performs the task of maintaining optimal levels of sodium and potassium in the blood by maintaining water balance and blood volume. Elevated levels of aldosterone are indicative of aldosteronism or hyperaldosteronism. The presence of a tumor may bring about high levels of aldosterone. Low levels of aldosterone may suggest diabetes or Addison's disease. Pregnant women may notice high values of aldosterone in the blood. Medications such as corticosteroids, diuretics, female hormones and hypertension drugs can affect the results of aldosterone test. Even the body posture can affect aldosterone levels in the blood. The amount of salt consumed can cause changes in blood aldosterone levels. Aldosterone test is conducted to study any possible overactivity of adrenal glands. Aldosterone test is conducted on a blood sample or 24 hour urine sample. Normal aldosterone range for urine is 2-80 mg/24 hr. Typical blood aldosterone range is 3-10 ng/dL when the patient is in supine position and 5 - 20 ng/dL when sitting upright.
ANA blood test
Antinuclear antibodies (ANA) refer to the unusual antibodies that are detectable in the blood. ANA are gamma-globulins type of antibodies that are found in patients with certain autoimmune diseases. ANA are directed against certain components found in the nucleus of a cell in the body. These antibodies have the capacity of binding certain structures within the nucleus of the cells. The ANA test was first designed by Dr.George Friou in 1957. The laboratory blood test exposes the antibodies in the serum of the blood to cells. It is then determined whether or not antibodies are present that react to various parts of the nucleus of cells. Hence the term 'anti-nuclear' antibody is used.
Fluorescence techniques are adopted to detect the ANA antibodies in the cells. Thus ANA testing is sometimes referred to as fluorescent antinuclear antibody test (FANA). Nowadays, a method to detect antinuclear antibodies called enzyme linked immunosorbent assay (ELISA) is replacing the previous method of immunofluorescent assay technique. The ELISA method is less likely to produce false positive ANA result than the previous method.
Patterns also give doctors a clue as to the type of illness to look for while evaluating a patient. For instance, the disease Scleroderma shows in nucleolar pattern. If a person does not have any autoimmune disease, it is defined in speckled pattern. An ANA blood test is used in patients who might be suffering from Sjogren's syndrome, rheumatoid arthritis, polymyositis, scleroderma, Hashimoto's thyroiditis, juvenile diabetes mellitus, Addison's disease, vitiligo, pernicious anemia, glomerulonephritis and pulmonary fibrosis. ANA can also be found in patients with conditions that are not considered autoimmune diseases such as chronic infections and cancer.
The result of ANA test is expressed in titers. A titer of 1 to 80 (1:80) means that antibodies could be last detected when 1 part of the blood sample was diluted by 80 parts of another liquid. Usually this other liquid is a diluted salt solution. A larger second number indicates that the antibodies are present in greater concentration. Therefore a titer of 1 to 320 indicated higher concentration of antibodies in the blood than a titer of 1 to 80. The normal values of ANA blood test is : Titer below 1: 20 or 1:40 depending on the test method used.
Positive ANA test result is suggestive of autoimmune disease. It can also mean that the patient has drug induced lupus. Some drugs and infections can also induce false positive ANA test results. Steroids can cause a false-negative result. Medications, especially antibiotics such as isoniazid, penicillin, and tetracycline, birth control pills, lithium and some diuretics such as chlorthalidone can interfere with the test and affect the accuracy of the ANA test result.
Pigmentation
Melanin is responsible for imparting color to the skin, hair and iris of the eyes. Levels of melanin depend on race and amount of sunlight exposure. Melanin production increases with exposure to the skin so as to protect the skin against harmful ultraviolet rays. Skin pigmentation disorders occur as a result of the body producing either too much or too little melanin. Skin pigmentation creates a darker or lighter skin tone that may be blotchy and uneven. Sun damage is probably the leading cause of skin pigmentation problems. Other factors include drug reactions, hormonal changes, genetic factors and medications.
Hormonal therapy, childbirth or birth control pills can cause skin pigmentation changes. Many people suffer from skin pigmentation problems as a result of locally increased skin pigment production. They appear as age spots, moles, liver spots or hyper pigmentation after local skin damage. Freckles are another variation in pigmentation of the skin. They are caused but by uneven release of the pigment.
Hypopigmentation or loss of skin pigmentation is a condition where the body does not produce sufficient melanin. Sometimes after an ulcer, blister, burn, or infection heals, the skin loses some of its pigment in that area. Albino is one who suffers total hypopigmentation at birth.
Vitiligo: Vitiligo is another form of hypo pigmentation caused by the loss of pigment-producing cells in the skin (melanocytes). These white patches are very sensitive to the sun. This skin pigmentation disorder affects nearly 2% of the population and is more evident in those with darker skin. Some scientists believe vitiligo may be caused by an autoimmune disorder. It is also linked to hyperthyroidism and Addison's Disease that affects the adrenal glands.
Hyper Pigmentation is a condition where the body produces too much melanin thereby causing it to become darker than usual. Hyper pigmentation can occur due to excessive sun bathing or drug reactions. Many a time wounds and scars leave a darker patch of skin. Birthmarks, moles, and aging spots are also indications of hyper pigmentation. It is important to keep on the alert for any change in size, color or texture for indications of skin cancer.
Lichen Simplex Chronicus: This skin pigmentation disorder is characterized by dark patches of skin accompanied with severe itching. This can lead to permanent scarring and infection if untreated.
Melasma: This hyper pigmentation condition is a fallout of pregnancy hormones. A dark mask appears over the cheeks, bridge of the nose and the neck. This skin pigmentation condition is also known as chloasma and can be treated with prescription creams and over-the-counter products.
Birthmarks: This type of skin pigmentation appears at birth or in the few weeks following birth. These birthmarks do not generally pose any health risks.
Port-wine Stains: These skin pigmentation spots are caused by abnormal development of capillaries and appear as a red or purple mark on the body.
Poikiloderma: This skin condition is characterized by areas of increased and decreased pigmentation; indicative of sun damage.
Bibliography / Reference
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