%A Constant-Desportes M %A Guelpa-Lauras C %A Carolina J %A Léoture A %A Grasset JH %A Sansarricq H %T A case of relapse with drug-susceptible M. leprae after multidrug therapy %0 Journal Article %D 1991 %J International Journal of Leprosy and other Mycobacterial Diseases %P 0148-916X %V 59 %N 2 %X A male born in 1930 was diagnosed as smear-positive borderline leprosy in 1971, and was treated with dapsone and/or sul-famethoxypyridazine f rom 1972 to 1980 with clinical improvement. However, new skin lesions with smears strongly positive appeared in August 1980, and he was diagnosed as having downgraded to lepro-matous (LL) leprosy, but the bacilli recovered f rom the skin biopsy were fully susceptible to both dapsone and rifampin by mouse foot pad technique. Between 1981 and 1983, the patient was treated with 24 months of rifampin 600 mg and dapsone 100 mg daily, supplemented with prothion-amide 500 mg daily during the initial 3 months, and his skin lesions gradually improved during treatment with the combined regimen. Afterward, the patient was kept under surveillance without treatment. f rom 1984 to 1986, his skin smears were negative, and no bacilli could be found f rom a skin biopsy taken in 1985. Then in 1987, 52 months after stopping treatment, new skin lesions appeared with a high concentration of Mycobacterium leprae (2 x 106/mg tissue). The drug-susceptibility test again demonstrated that the organisms were fully susceptible to both dapsone and rifampin. Apparently the relapse was due to re-multiplication of drug-susceptible persisters.