Biomedical subjects
Publications and source records attributed to N Burdash.
During a 25-year period, four types of hepatitis-causing virus have been identified and can now be evaluated serologically. This final article in this clinical laboratory medicine series reviews routes of virus transmission and persistence and the availability of tests.
Clinical differentiation between a virus and beta-hemolytic streptococci as a cause of pharyngitis remains difficult. In the physician's laboratory, more rapid procedures using immunologic methods have replaced culture methods, traditionally requiring 2 to 3 days for identification of beta-hemolytic streptococci. Attention to the diagnostic sensitivity and specificity of these procedures will guide appropriate use.
Lyme disease is a common inflammatory disease of North America. It is caused by the spirochetal bacterium Borrelia burgdorferi, which is transmitted by the bite of a small tick, Ixodes dammini. The disease is inconsistent in its manifestation, mimicking a wide variety of maladies, many of which are noninfectious. Currently, there is no practical means for detection of the presence of the organism, and serologic studies offer the best diagnostic aid. High titers of either immunoglobulin G (IgG) or immunoglobulin M (IgM) antibodies to B burgdorferi antigens indicate disease, but lower titers can be misleading. The IgM antibodies may remain after the initial infection, and IgG antibodies may remain for years. Antibiotic therapy early in the infection may interfere with antibody production, but therapy later does not appear to have a significant effect on antibody levels. Because several methods are available for the detection of antibodies and several choices for antibody detected--IgM, IgG, or combinations--the clinical laboratory should provide guidance and advice in choosing and interpreting tests.