[Evaluation of conventional and new generation tests for testing the humeral response to Mycoplasma pneumoniae antigens in natural infection in humans. I. Occurrence and level of mycoplasma antibodies in clinically healthy subjects].

The aim of the first stage of investigation was to determine, using the complement fixation test (CFT), immuno-electroprecipitation test (IEPT) and ELISA, the level of mycoplasmal antibodies in serum samples obtained from 114 clinically healthy persons (49 samples from children and youth up to 20 and 65 samples from blood donors). On the basis of obtained findings, antibody titer assumed to be diagnostically significant was determined on the means + 3 SD level in each test. Thus in the CF test the assumed titer > or = 20, in the IEP test--titer > or = 2, in the ELISA-IgA--titer > or = 100, in the ELISA- IgG--titer > or = 1600, in the ELISA-IgM--titer > or = 1200, in the ELISA -IgA + G + M--titer > or = 3200. The study allowed to establish that on with age the level of mycoplasmal antibodies in immunoglobulin of classes A and G rose while the titer of these antibodies of class IgM remained on the same level in persons up to 20 and then decreased almost twice in adults. It was also found that in all age groups the mean values of titer of antibodies against M. pneumoniae calculated for each test were lower than titer assumed to be diagnostically significant.