STUDIES ON ANTITUBERCULOUS AGENT-INDUCED HYPERSENSITIVITY BY LEUCOCYTE MIGRATION INHIBITION TEST

Abstract

In 17 patients suspected of hypersensitivity to antituberculous agents, the identities of the allergenic drugs were determined by leucocyte migration inhibition test (LMIT). The evaluation of LMIT and the involvement of delayed-type hypersensitivity (DTH) were investigated for hypersensitivity induced by antituberculous agents. The overall sex distribution was 11 males and 9 females, and all cases were over 50 years old. These consisted of 9 cases of skin eruptions, 5 of hepatopathy, 5 of pyrexia. 1 of pneumonititis, 1 of pulmonary infiltration with eosinophilia syndrome and 1 of thrombocytopenia. Also, the categories of allergic symptoms overlapped to some extent in the cases with concomitant symptoms. An LMIT was performed using an indirect agarose-plate method. The antigen concentration was 50μg/ml for isoniazide (INH) or ethambutol (EB), and 10μg/ml for rifampicin (RFP). The LMIT-positive rate was 88% for all 17 cases. Leucocyte migration activating factor (LMAF) and leucocyte migration inhibitory factor (LMIF) were detected in 71% and 29%, LMAF being found significantly (p<0.01) more often than LMIF The LMIT-positive rate for each antituberculous agent was 12% for INH, 65% for RFP and 31% for EB, (RFP having the highest rate of the three drugs). LMAF and LMIF were detected at 59% and 6%, with RFP, LMAF being found significantly (p<0.0005) more often than LMIF Our findings indicate that LMIT is valuable in detecting the causative drugs in antituberculous-agent-hypersensitive patients, and DTH plays a major role in the pathogenesis of this hypersensitivity. RFP has the highest allergenicity in antituberculous agents, while LMAF is highly involved in DTH induced by RFP