Skin lesion of Blastomycosis

Definition:

A rare infection caused by the yeast-like fungus Blastomyces dermatitidis, which resides in dead wood and soil.

Causes, incidence, and risk factors:

Blastomycosis is a rare fungal infection. It usually affects only the skin, but it may also become systemic, affecting internal areas including the lungs, kidneys, urinary/genital system, and bones.

The limited cutaneous (skin) form is most commonly seen in young men in North America, especially the southern and midwestern U.S. and Canada, but the disorder also occurs in Africa and Latin America.

The infection is similar to other yeast-like fungal infections, with skin lesions that may spread locally or spread into the body (disseminate). The lesion usually begins at the site of a skin injury such as a cut, bruise, or scrape. The initial lesion spreads locally on the surface of the skin, leaving behind a central scar. It may persist for long periods, mimicking skin cancer in appearance.

Immunocompromised people such as those with AIDS are at increased risk for disseminated blastomycosis.