Rosai-Dorfman disease.

Sinus histiocytosis with massive lymphadenopathy, also known as Rosai-Dorfman disease, is a rare histiocytic proliferative disorder of unknown aetiology. The classic presentation of Rosai-Dorfman disease is massive, bilateral, painless cervical lymphadenopathy. Extranodal disease is also common, often with a particular predilection for the head and neck regions. We report a rare case of Rosai-Dorfman disease with nodal and multiple extranodal manifestations in a 13-year-old girl. The patient had cervical and mediastinal lymphadenopathy, multiple soft tissue swellings of the scalp, bilateral proptosis and goitre due to thyroid gland involvement. She responded to steroids, with remission of the swellings and symptoms. This case is being reported for its rarity, multiple extranodal manifestations and thyroid gland involvement. Thyroid gland involvement in Rosai-Dorfman disease has rarely been reported in the literature.