Erythroderma‐Like Manifestations and High Fever in Palisaded Neutrophilic and Granulomatous Dermatitis Without Any Underlying Systemic Immunological Disease

Palisaded neutrophilic and granulomatous dermatitis (PNGD) is a reactive granulomatous dermatitis; the umbrella term includes interstitial granulomatous dermatitis and interstitial granulomatous drug reaction, in addition to PNGD. The histological findings of PNGD include leukocytoclastic vasculitis, neutrophilic infiltrates, and collagen degeneration with palisades of histiocytes and small granulomas. Clinically, the patients show symmetrical, smooth papules that are skin-colored to red, some with central umbilication or crusting, located mainly on the elbows and extremities. PNGD usually occurs with some systemic diseases, such as systemic lupus erythematosus, suggesting a cutaneous reaction pattern due to underlying internal inflammation. Although the present case was histologically diagnosed as PNGD, while excluding other granulomatous diseases, multiple indurated erythematous papules with a tendency to coalesce widely were seen, mimicking erythroderma without any underlying immunological diseases. In addition, the eruption coincided with fluctuating high fever. This was a rare case of PNGD with no underlying immunological disease that presented with severe manifestations such as fever and erythroderma.