Asymptomatic intestinal microsporidiosis in a human immunodeficiency virus-seronegative, immunocompetent Zambian child.

Most detected cases of microsporidia have involved immunocompromised patients. For example these parasites are a frequent cause of diarrhea and biliary illness in HIV patients. One study identified a case of asymptomatic intestinal Enterocytozoon bieneusi infection in an HIV-seronegative immunocompetent Zambian child. The case was detected through a population-based survey conducted in Zambias Samfya district in 1994. Stool samples from 176 children were examined for microsporidia spores and HIV serostatus was determined. The one case of electron microscopy-confirmed E bieneusi involved a 7-month-old HIV-negative boy of good nutritional status. All other laboratory findings were normal. The boys mother reported no history of diarrhea in the preceding 2 weeks. Repeat stool testing at 16 and 28 months of age failed to reveal microsporidia and the child remained HIV-negative. This case suggests that E bieneusi may be a naturally occurring parasite in asymptomatic immunocompetent individuals.