[Intestinal spirochetosis in homosexuals infected with HIV. 3 cases].

We report 3 cases of intestinal spirochetosis in homosexuals infected with the human immunodeficiency virus (2 group III and 1 group IV C1, according to the Centers for Disease Control classification) presenting with moderate, chronic diarrhea. The diagnosis was made based on the histological examination of colorectal biopsies showing a layer of spirochetes carpeting the epithelium. Electron microscopy evaluation and culturing of the microorganism provided information on the bacterium's morphology. Metronidazole effectively treated the diarrhea. Intestinal spirochetes, whose existence has been recognized for more than a century, constitute a heterogeneous group of bacteria whose pathogenic role in man remains controversial. The systemic search for these organisms in a large series of patients would help to situate their place among the various etiologies of infectious diarrhea in immunodepressed subjects.