Granulomatous rosacea-like skin rash: extranodal Rosai-Dorfman disease.

We report a 38-year-old man who presented with bilateral conjunctival congestion, hoarseness, and progressively growing pruritic, infiltrated skin lesions that had first begun over the face and neck, and later spread to the trunk and the limbs in 4 months. The clinical appearance of the lesions mimics granulomatous rosacea, acne vulgaris, or pityrosporum folliculitis. Histopathologic examination of the lesions from the face and chest both revealed dense dermal nodular lymphohistiocytic infiltrates which were positive for CD68 and S-100, but negative for CD1a. A systemic work-up for him detected no lymphadenopathy or other systemic involvement. A diagnosis of extranodal Rosai-Dorfman disease was made, and the patient received systemic glucocorticoids, with considerable improvement after 4 months of therapy.