Rectal spirochaetosis--symptomatic response to metronidazole and mebendazole. A case report.

A white homosexual man presented with a 6-week history of intermittent diarrhoea, abdominal pain, nausea and malaise. Threadworm infestation was present, but other gastro-intestinal infection was excluded. Rectal spirochaetosis was found on examination of a rectal biopsy specimen. The patient's symptoms disappeared and the rectal tissue returned to normal on biopsy after treatment with metronidazole and mebendazole. It is suggested that the symptoms were directly related to the presence of rectal spirochaetosis, which responded to the antibiotic.