Detection of Mycobacterial antigen and antibody in patients with tuberculosis and their association with therapy

Background: Little is known about changes in total antibodies occurring during the progression of tuberculosis or its treatment. Using passive and reverse passive hemagglutination methods, mycobacterial antibody and antigen were determined in sera of patients with acute smear-positive pulmonary tuberculosis.Methods: Fifty-nine patients were studied in different groups according to the duration of treatment in various stages of disease. The first group that did not undergo treatment showed a very low level of antibody. The second group with less than 6 months of therapy had a mean antibody titer of about 1:70. The third group underwent therapy for more than 6 months and their mean antibody titer was about 1:970. The fourth group whose disease was under control and their treatments were discontinued, showed the highest level of antibodies(1:2760). Results: A significant difference was found between the average antibody titers and the duration of treatment and course of disease. No antigen was detected in any patients except in group 5.Conclusion: A high antibody response seemed to occur after treatment when the bacteria were disrupted and their antigens released. Absence of antigen may be due to the formation of antigen-antibody complexes.