Optic Neuritis
Optic neuritis is a condition where the optic nerve gets inflamed. Due to the inflammation, light and visual images are not clearly transmitted to the brain. Optic neuritis can be caused by autoimmune diseases such as multiple sclerosis or viral infections such as chicken pox or measles. Optic neuritis is usually the first sign of multiple sclerosis. This condition tends to affect more women than men.
Patients suffering from optic neuritis notice reduced vision. This is more so when the body temperature is elevated. The eyes are sore and painful when moved. There is reduced color perception and diminished peripheral vision. Persons suffering from optic neuritis may have headache and fever. The vision diminishes for about a week and then gradual improvement is noticed. Typically most patients suffering from optic neuritis tend to recover most of their vision within about 6 months.
The opthalmologist will test the patient's color vision and visual field. Eye presure and pupillary function will be examined. The optic disc is viewed with indirect ophthalmoscopy. Brain MRI may be taken for testing for multiple sclerosis. Intravenous steroid medication has shown results on those suffering from initial occurence of optic neuritis.
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.
Immunologist
An Immunologist can be described as a medical specialist trained to prevent, diagnose, manage and treat diseases that result from abnormalities of the immune system. Immunologists are highly qualified and trained to treat immune system disorders such as allergies, asthma, inherited immunodeficiency diseases and autoimmune diseases. Clinical immunologists and allergy specialists undergo similar training as with any other medical specialists. After completion of four years of premedical education at a college or university, they receive atleast four years of medical school education. After receiving general training in internal medicine, they receive additional training in immunology and allergy areas. Immunologists are involved in a gamut of work areas, in hospitals, private practice, diagnostic immunology laboratories, research centers and industrial houses. The medical immunologist or allergy specialist primarily identifies and treats the diseases that result from abnormalities of the immune system.
- Patients are referred by a general physician for further diagnosis, confirmation and management of clinical disorders of the immune system.
- Patients seeking the advice of an immunologist for education regarding disorders of the immune system.
- Patients suffering from life threatening allergies such as anaphylaxis.
- When food or occupational allergy is suspected, the patient is referred to an immunologist.
- When a physician contemplates immunotherapy for treatment of allergic diseases, the patient is sent to the immunologist.
- Patients suffering from asthma exhibiting continuing poor control despite regular use of asthma medication.
- Patients with unexplained inflammation such as fevers of unknown origin, unexplained fevers, weight loss.
- For investigation of recurrent or unusual opportunistic infections.
Bibliography / Reference
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