Toxoplasma Antibody Assay

The damage of the toxoplasma to humans is mainly directed at children and pregnant women. Children may invade the cranial nerves and cause symptoms such as cerebral rheumatism. For pregnant women, if they infect the toxoplasma within the first three months of pregnancy, it will cause miscarriage, teratogenicity and The consequences of fetal head dysplasia, if infected in the fourth month of pregnancy, have no effect on the fetus. If there is a toxoplasma infection, the body will produce the corresponding antibodies, so the antibody test is positive. Basic Information Specialist classification: maternal checkup classification: pathogenic microbiological examination Applicable gender: whether women are fasting: not fasting Analysis results: Below normal: Normal value: no Above normal: negative: A negative test result indicates that the body may be in a normal condition. Positive: A positive test indicates that the subject may have a Toxoplasma infection. Tips: When checking, the patient should actively cooperate with the doctor and carefully operate to avoid the result. Normal value Toxoplasma antibody IgG, titer 1:256 or less; staining test with a titer of less than 1:16, negative. Clinical significance Abnormal results Enzyme-linked immunosorbent assay for the determination of toxoplasma antibody IgG with a titer of 1:256 or more; the staining test was positive with a titer greater than 1:16. Need to check the crowd for pregnancy or early maternity checkup. Positive results may be diseases: cerebral toxoplasmosis, toxoplasmosis encephalopathy Requirements for examination: The patient actively cooperates with the doctor and carefully operates to avoid incorrect results. Inspection process 1. The antigens used for detecting antibodies mainly include tachyzoite soluble antigen (cytoplasmic antigen) and membrane antigen. The former antibody appeared earlier (detected by staining test, indirect immunofluorescence test), while the latter antibody appeared later (detected by indirect hemagglutination test or the like). At the same time, multiple methods can be used to detect complementary effects and increase the detection rate. Since Toxoplasma gondii can exist for a long time in human cells, it is generally difficult to detect the current infection or the previous infection by the detection antibody, and it can be judged according to the level of the antibody titer and the change of its dynamics. Commonly used detection methods are: (1) Dyeing test (Sabin-Feldman DT): Detection of IgG antibody. It is positive 1 to 2 weeks after infection, and the antibody titer peaks at 3 to 5 weeks, and then gradually decreases, and can be maintained for many years. Antibody titer 1: positive suggestive of latent infection; 1:256 active infection 1:1024 for acute infection. The disadvantage is that it requires live insects to operate. (2) Indirect fluorescent antibody assay (IFAT): detection of IgM and IgG antibodies. It is sensitive, specific, fast, and reproducible, and is basically consistent with DT. However, if rheumatoid factor and antinuclear antibody are positive, it can cause false positive reaction. Serum antibody titer 1:64 is a previous infection, the same as DT. (3) Indirect hemagglutination test (IHA): The test method is simple. High compliance with DT results. However, it usually appears to be positive about one month after the illness. The result is judged as IFAT. Poor repeatability and sensitization of red blood cell instability and its disadvantages. (4) Enzyme-linked immunosorbent assay (ELISA): IgM and IgG antibodies can be examined. And there are advantages such as high intensity and high specificity. It can also be used for antigen identification. In recent years, a number of new and new assays have been created and derived on the basis of ELISA, such as gold grape A protein (SPA)-ELISA; horseradish peroxidase-labeled SPA substituted enzyme second antibody for ELISA (PPA) - ELISA); avidin-biotin (ABG) ELISA; gel diffusion (DIG)-ELISA; spot (DDT)-ELISA and monoclonal antibody (McAb)-ELISA and other more sensitive and specific methods. (5) Radioimmunoassay (RIA): highly sensitive and specific. 2. Detection of antigenic lines Immunological methods are used to detect pathogens (tachyzoites or cysts) in a host cell, metabolism or lysates (circulating antigens) in serum and body fluids. It is a reliable method for early diagnosis and diagnosis. Scholars around the world have established McAb-ELISA and sandwich ELISA for McAb and polyclonal antibody to detect serum circulating antigen in acute patients. The sensitivity is to detect 0.4μg/ml antigen in serum. The intradermal test was performed on the infected rat peritoneal fluid or chicken embryo fluid. Delayed, tuberculin reactions often occur. Can be used as an epidemiological survey. There are currently not many applications. Not suitable for the crowd The test was non-invasive and had no specific contraindications. Adverse reactions and risks This test is a non-invasive test that does not cause serious complications or other hazards.