Disseminated Mycobacterium simiae infection in patients with AIDS

Objectives: To report our experience with disseminated Mycobacterium simiae disease in patients with AIDS, and review other cases reported in the lite rature. Methods: We retrospectively reviewed all cases of M. simiae that were isola ted from sterile body sites over a 9-year period at the University Health S ystem Hospital at San Antonio, Texas, U.S.A. Data included patient demograp hics, clinical features, other accompanying opportunistic infections, in vi tro susceptibility, therapy and outcome. Results: Ten cases of M. simiae disseminated disease were identified. All o f them were inpatients with AIDS, Another nine cases of disseminated infect ion in AIDS patients were reported in the literature. Advanced AIDS with ab solute CD4 counts of less than 50 and an associated AIDS-defining illness c haracterized all cases. Persistent fever and debilitation without localizin g signs were the most common clinical features. Our patients responded poor ly to antimycobacterial drugs and died within 6 months of diagnosis. The on ly reported successful therapy was in patients who responded well to highly active antiretroviral therapy and antimycobacterial regimens containing cl arithromycin, ethambutol and ciprofloxacin, Conclusions: Clinical presentation of M. simiae infection mimics Mycobacter ium avium complex, with fever and progressive debilitation, but is less res ponsive to therapy. Immuno-reconstitution with potent antiretroviral therap y may be the best therapy for such resistant disease. (C) 2000 The British Infection Society.