SERODIAGNOSIS OF TUBERCULOSIS - DETECTION OF MYCOBACTERIAL ANTIBODIESAND ANTIGENS

Setting: The diagnosis of tuberculosis is based primarily on identific ation of mycobacteria and on clinical evidence. Recently, serological studies have been widely used experimentally as a diagnostic approach. Objective: The aim of our study was to optimize serodiagnosis of tube rculosis by detecting mycobacterial antigens and antibodies in sera fr om patients with lung tuberculosis, non-related diseases and healthy c ontrols. Design: Mycobacterium tuberculosis H37Rv was disintegrated by pressure. Cell walls were extracted with 3 M KCL and were subjected t o gel filtration in Toyopearl gel. Immune sera were prepared by immuni zation of rabbits with cell wall material. Anti H37Rv antibodies were purified by affinity chromatography. The reagents obtained were used t o detect serum antibodies and antigens (following immune complex disso ciation) using ELISA. Results: Using fraction 6 of cell wall extract, antibodies were detected in 72.2% of TB patients; there were no positi ve reactions in control subjects. By use of affinity-purified antibodi es, antigens were detected in 77.1% of TB patients, 10% of patients wi th unrelated diseases and 6.7% of healthy controls. Conclusion: Effect ive serodiagnosis of tuberculosis can be achieved only by combining de tection of both circulating antibodies and antigens using highly speci fic purified reagents and immune complex-dissociated sera.