Palisaded neutrophilic and granulomatous dermatitis: An unusual cutaneous manifestation of immune-mediated disorders

Palisaded neutrophilic and granulomatous dermatitis (PNGD) is an uncommon skin eruption most often associated with rheumatoid arthritis and other immune-mediated diseases. We present 4 cases to familiarize rheumatologists with the clinical presentation and histopathology of PNGD. We report 4 cases to illustrate the clinical and histologic spectrum of this rare skin disease found in rheumatologic patients. The disease pathogenesis and treatment options are discussed. All 4 patients presented with symmetric erythematous-to-violaceous papules and plaques that, upon biopsy, revealed a dermatitis composed of variable numbers of histiocytes and neutrophils. Some cases responded to topical corticosteroid treatment or to dapsone, whereas others resolved spontaneously. PNGD is a rare cutaneous finding in patients with a variety of immune-mediated systemic diseases, most often rheumatoid arthritis. It is a benign condition that may spontaneously remit or may respond favorably to topical corticosteroids or dapsone.