Department of Internal Medicine, NRITLD, Shahid Beheshti University, M.C., TEHRAN-IRAN.
Sinus histiocytosis with massive lymphadenopathy (SHML), Rosai-Dorfman Disease, is a rare histiocytic syndrome first described by Rosai and Dorfman, seen predominantly in childhood and early adulthood. Even though it is considered a benign disease, fatalities may occur due to cellular infiltrates of SHML. We report a 16–year–old boy with signs of polydypsia, polyuria, weight loss and generalized lymphadenopathy. He had been receiving corticosteroid following the diagnosis of histiocytosis X. Due to hyperglycemia, the patient was admitted with the primary diagnosis of diabetic ketoacidosis and medications were initiated. All paraclinical and immunologic examinations were negative. Axillary lymph node biopsy revealed the diagnosis of Rosai–Dorfman disease. (Tanaffos 2007; 6(3): 65-67)