Also known as: superficial granulomatous pyoderma, atypical plaque-like folliculitis in HIV, vegetative pyoderma gangrenosum

Clinical Features:

• An exaggerated inflammatory reaction to bacterial infection, especially Staphylococcus aureus, Pseudomonas aeruginosa and β-hemolytic streptococci.
• Typically affects patients with immunosuppression or lymphoproliferative disorders
• Presents with single to disseminated verrucous plaques with multiple pustules, usually affecting the head and neck, extremities or intertriginous areas
• This disorder typically responds well to antibiotics.
• The causative organism can usually be cultured from the lesions, even if it is not apparent on Gram stain.

Histologic Features:

• A diffuse mixed inflammatory infiltrate is present in the upper reticular dermis.
• The infiltrate often displays a zonation effect: a central area of neutrophils and a few eosinophils is surrounded by macrophages and giant cells, which are surrounded by a peripheral rim of lymphocytes and plasma cells.
• Pseudoepithelial hyperplasia is often present.
• The inflammation may center on the hair follicles in some cases.

Cases associated with this book:

Blastomycosis-like pyoderma
Author: Artur Zembowicz M.D. Ph.D.

Conference: Dermpedia Teaching Collection