[Erythema elevatum diutinum associated with pyoderma gangrenosum in an HIV-positive patient].

BACKGROUND: Erythema elevatum diutinum (EED) is a very rare form of chronic dermatosis clinically characterised by reddish-violet papular nodules extending to the surfaces of the limbs and extremities. Histologically, there are classically two phases of progression initially involving associated neutrophilic dermatosis and leucocytoclastic vasculitis, which is later followed by fibrosis of characteristic appearance. We report the association of EED and pyoderma gangrenosum in a patient infected with HIV. PATIENTS AND METHODS: A 53-year-old male seen since 1989 for HIV infection had been presenting firm bilateral and symmetrical nodules on the feet for 6 months. Histological analysis of one of these nodules resulted in diagnosis of chronic erythema elevatum diutinum and treatment with dapsone was initiated. Three months later, despite regression of the EED lesions under dapsone, two large pustules appeared on the outer aspect of the right leg; they were confluent and progressed towards a superficial ulcer with rounded edges with a clinical appearance evocative of pyoderma gangrenosum (PG). Histopathological analysis demonstrated a massive dermal infiltrate beneath the ulcer comprising neutrophils with evidence of leucocytoclasia, all of which militated in favour of the diagnosis of pyoderma gangrenosum. DISCUSSION: We report for the first time the association of two forms of neutrophilic dermatosis, EED and PG, in an HIV-positive patient. This case report and certain data in the literature suggest that the various forms of neutrophilic dermatosis tend to result in a range of lesions rather than in clearly distinct entities. Copyright 2010 Elsevier Masson SAS. All rights reserved.