Botryomycosis caused by Staphylococcus aureus and Pneumocystis carinii in a patient with acquired immunodeficiency disease.

Botryomycosis is an uncommon, chronic, granulomatous and/or suppurative, opportunistic infection affecting the skin and viscera, primarily caused by bacteria. The exact pathogenesis of this infection is not well understood. However, both the host's immune status and microbial infectivity have been implicated in the pathogenesis of this unusual clinical condition. To date, botryomycosis caused by a nonbacterial pathogen has not been reported in the literature. We report a case of cutaneous botryomycosis caused by combined Staphylococcus aureus and Pneumocystis carinii. Cutaneous P. carinii infection without pulmonary involvement is extremely rare.