ADENOVIRUS MASQUERADING AS MICROSPORIDIA

Enterocytozoon bieneusi is a microsporidian that causes a severe, debi litating, chronic diarrhea in some patients with the acquired immunode ficiency syndrome. Specific diagnosis of E. bieneusi currently require s an invasive biopsy procedure and time-consuming preparation of speci mens for electron microscopy. Our attempts to establish an in vitro cu lture system using mammalian cell cultures inoculated with duodenal as pirates, biopsy, or both, from 2 infected patients resulted in inadver tent coculture of an adenovirus and E. bieneusi. The adenovirus-infect ed cells deceptively appeared to contain spores of microsporidia based on light microscopic examination. Transmission electron microscopy re vealed only a few microsporidia, but numerous cells infected with an a denovirus that was subsequently identified as adenovirus type 8. We be lieve that adenovirus infections prevented the cultured cells from sup porting the proliferation off. bieneusi and ultimately destroyed the c ell cultures.