Dematiaceous molds
From IDWiki
- Phenotypic grouping of fungi based on the presence of melanin
Background
- Melanin is a virulence factor which protects again proteolytic enzymes, oxydation, and phagocytosis
- Includes so-called "black yeast", which appear yeast-like early in culture
Clinical Presentations
- Phaeohyphomycosis typically refers to cutaneous, subcutaneous, and disseminated disease, and is often acquired by traumatic innoculation
- Superficial cutaneous infection
- Subcutaneous phaeohyphomycosis
- Disseminated disease, more common in immunocompromised patients
- Chromoblastomycosis
- Mycetoma
| Disease | Organisms | Notes |
|---|---|---|
| Localized cutaneous infection or abscess | Alternaria species, Exophiala species, Phialophora species | Traumatic inoculation. Can become disseminated if immunocompromised. |
| Mycetoma | Madurella species, Exophiala jeanselmei, Leptosphaeria species | Spectrum from cutaneous to deep bone. Chronic draining, including granules. |
| Chromoblastomycosis | Cladophialophora carrionii, Fonsecaea species, Phialophora species | Chronic subcutaneous infection with sclerotic or muriform bodies |
| Keratitis | Most common in India. Usually from traumatic inoculation | |
| Black piedra | Piedraia hortae | Present in the tropics. Involves only the hair. |
