Ecthyma gangrenosum: an unusual cutaneous manifestation of the head and neck.

Ecthyma gangrenosum (EG) is a recognized cutaneous infection commonly associated with Pseudomonas aeruginosa bacteremia. It typically occurs in patients who are septic and severely immunocompromised. Clinical presentation characteristically begins as an erythematous or hemorrhagic vesicle or bulla, which evolves into a necrotic ulcer with eschar and surrounding erythema. This was first described in association with Pseudomonas septicemia by Barker in 1897 and was later given the name "ecthyma gangrenosum" by Hitschmann and Kreibich.