Atypical presentation of co-existent Haemophilus ducreyi and Treponema pallidum infection in an HIV-positive male.

A 25-year-old homosexual black male presented with asymmetrical perianal ulceration of uncertain clinical origin. Indepth microbiological examination revealed the combined presence of Haemophilus ducreyi and Treponema pallidum. The atypical clinical appearance may have been due to the changed immunological status of the host's being infected with Human Immunodeficiency Virus.