Phaeohyphomycosisis an infection with dematiaceous fungi that most commonly affects immunocompromised patients. The disease presents with nodulocystic lesions and may recur over the years.

It is a rare fungal infection caused by a various genus of dematiaceous fungi that are characterized by the presence of melaninlike cell wall pigments considered to hinder immune clearance by scavenging phagocyte-derived free radicals locally. The fungi are ubiquitous in soil and vegetation and usually penetrate the skin at sites of minor trauma.

The patients with subcutaneous phaeohyphomycosis can present with nodules, cysts, tumors, and/or verrucous plaques. The diagnosis needs a clinicopathologic correlation. Rapid diagnosis is made based on the observation of septate brown hyphae and/or yeast forms. There is no standard treatment of phaeohyphomycosis. Typical management comprises of azole therapy; however, excision with close follow-up is considered a reasonable alternative

Reference:

Turner N, Kibbi N, Panse G, ImaedaS. Recurrent cutaneous Exophiala Phaeohyphomycosis in an immunosuppressed patient. Cutis. 2020; 106(5): E7-E8.