Rosai-Dorfman disease with cutaneous plaques and autoimmune haemolytic anemia.

Sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease) is a non-Langerhan cell histiocytosis which primarily involves lymph nodes. Extranodal involvement in the form of cutaneous plaques can occur and can pose a diagnostic challenge because of pleomorphic presentation and histopathological mimics. Rarely, systemic autoimmune involvement may complicate the disease process. We present a 28-year-old woman with slowly evolving scaly erythematous cutaneous plaques and fluctuating lymphadenopathy, associated with autoimmune haemolytic anaemia. The patient responded favourably to oral corticosteroids and acitretin with significant flattening of cutaneous plaques, reduction in size of neck nodes and improvement of anaemia.