در اهداكنندگان خون A06 ضدآنتي ژن مايكوباكتريايي IgG ، IgM سرو اپيدميولوژي آنتي باديهاي

A seroepidemiologic survey of serumic IgG and IgM Against A60 antigen in healthy blood donors

Because of the world wide spread of infectious mycobacteria, awarness of quantity of community contact with this microorganism is a necessity. Serologic assays are one of the major tools for determining the history of cantact and contamination of people with mycobacteria. We used an enzyme-linked immunoabsorbent assay (ELISA) test to assess serum antibodies IgG and IgM against antigen 60 (anti-A60). These tests were applied to 542 healthy blood donors reffering to Kermanshah Blood Bank. Out of 542 healthy individuals, 280 cases (51.7%) were negative for anti-A60 IgG, 112 cases(20.7%) were suspicious and 150 cases (27.7%) were found positive. Out of 542 healthy individuals, 399 cases (73.6%) were negative for anti-A60 1gM, 58 cases (10.7%) were suspicious and 85 cases (15.7%) were found positive. There was no meaningful correlation between area of living, history of BCG vaccination, level of education, job, financial status, sex and mean rank of serum concentrations of IgG and IgM (P>0.05). There was a meaningful correlation between ages of blood donors and their IgM serum (and not IgG) level (P<0.001). The least seropositive cases (21.18%) were found in the, first age group (17-24 years old). In the second age group (25-34 years old), the seropositive cases were greather than the other two groups. Among seropositive cases, 45 persons (52.94%) were in the second group. The least seronegative cases, were found in the third age group (88 cases). These individuals (166 cases) covered 84.7% of population of the third group and 41.6% of seronegative cases. Additionally, the first group included the least suspicious cases (12 cases) and seropositives (18 cases). In general, the most members of each group were seronegatives. Determining the correlation between age and serum IgM, we evaluated the correlation between age and other variations. Among the variations, there was a meaningful relation between age and job; mainly, members of the first age group were soldiers (49 cases-25%), students (45 cases-23%) and unemployed persons (24 cases-12.2%). We suppose that considerable presence of anti-A60 IgG and IgM antibodies are because of endemicity of mycobacteria in the area. At this situation, a considerable number of people, suffer from inapparent infections and are in a "persistent state". By the way, A number of positive results can be considered as a false positive results (because of community of A60 among mycobacteria and cross-reaction of A60 among mycobacteria). So we recommend changing the serumic dilution and cut-off point of the test before doing the same study in our country. We suggest that the higher number of seronegaitves in the. first group age may be due to their contact circumstances with mycobacteria and quality of their humoral immunity function.