Serious side effects of rifampin on the course of WHO/MDT: a case report.

A male born in 1935 was diagnosed as having lepromatous leprosy when he was 17 years old. In addition to dapsone (DDS) monotherapy, he had been treated with rifampin (RMP) for 2 terms: first with 450 mg a day for 2 years when he was 39 years old; second with 150 mg a day for 2 months after a 1-year interval from the first regimen. During these entire courses with RMP, no complication was noted. When he was 64 years old in 1999, a diagnosis of relapsed borderline tuberculoid (BT) leprosy was made, and he was started on the multibacillary (MB) regimen of the World Health Organization multidrug therapy (WHO/MDT). After the third dose of monthly RMP, he developed a flu-like syndrome and went into shock. A few hours later, intravascular hemolysis occurred followed by acute renal failure. He was placed on hemodialysis for 7 series and recovered almost completely about 2 months later. The immune complexes with anti-RMP antibody followed by complement binding may have accounted for these symptoms. Twenty-four reported cases of leprosy who had developed side effects of RMP under an intermittent regimen were analyzed; 9 of the cases had had prior treatment with RMP but 15 had not. Adverse effects were more likely to occur in MB cases and were more frequent during the first 6 doses of intermittent regimens. The cases with prior treatment with RMP had had a higher incidence of serious complications such as marked hypotension, hemolysis and acute renal failure. However, many exceptions were also found, and we could not verify any fully dependable factor(s) to predict the side effects of RMP. More field investigation is desirable, and monthly administration of RMP must be conducted under direct observation through the course of WHO/MDT.