Microsporidial polymyositis in human immunodeficiency virus-infected patients, a rare life-threatening opportunistic infection: clinical suspicion, diagnosis, and management in resource-limited settings.

INTRODUCTION: Microsporidial myositis is a rare opportunistic infection that has been reported in HIV-infected and HIV-uninfected immunocompromised patients.

METHODS: In this study we present a retrospective analysis of 5 cases of microsporidial myositis in HIV-infected patients, including the clinical, laboratory, and histologic features, and a review of the literature.

RESULTS: Five young men with HIV infection [median CD4 count of 20 cells (range 14-144)/mm(3) ] who presented with signs and symptoms suggestive of myositis underwent EMG-NCV and muscle biopsy, which revealed signs compatible with microsporidial myositis. Early and aggressive treatment led to improvement in 3 patients. Two of the 5 patients died due to a delay in diagnosis, because the spores were mistaken for Candida without confirmatory stains or a high index of suspicion.

CONCLUSIONS: Myositis in HIV-infected patients with low CD4 counts should be evaluated using muscle biopsy. A high index of suspicion is required for early diagnosis of microsporidial myositis in HIV-infected patients. Early diagnosis and immediate, aggressive treatment are the keys to favorable outcomes in these patients.