Botryomycosis presenting as nasal cutaneous fistulas caused by Prevotella melaninogenica.

Botryomycosis is an uncommon chronic suppurative granulomatous bacterial infection that can affect the skin and viscera. Clinically, lesions typically consist of small tender nodules from which draining sinuses may develop to expel a purulent discharge. Histopathological features include characteristic aggregation of microorganisms (grain) within the inflammatory infiltrate. The commonest causative organisms are Staphylococcus aureus and Pseudomonas aeruginosa, of others. Botryomycosis resulting from Prevotella melaninogenica has not been reported previously. We report the case of a middle-aged patient with botryomycosis presenting as nasal cutaneous fistulas caused by P. melaninogenica, which was successfully treated with surgical intervention combined with systemic antibiotic treatment.