The effect of dapsone in high and normal dosage on the clinical and cell-mediated immune status of patients with borderline (BT-BL) leprosy

Abstract

Twenty-six patients with untreated borderline leprosy, 16 of whom (R group) had red raised lesions indicating incipient reversal reaction, were allotted randomly to dapsone 1 mg or 4 mg/kg body weight/day for the initial 2 months of treatment. The R group patients on high dosage dapsone did not show significantly greater clinical improvement during the trial period . Before treatment,their immune response (leucocyte migration inhibition test) to sonicated (but not whole) M. Leprae was higher than that of the 10 patients with macular lesions (Q group). The response of Q group patients was unaffected by dapsone treatment, but in R group patients the response was reduced to Q group level after 1 month of dapsone treatment (both dosages). This suppression persisted for a week when dapsone was temporarily discontinued.