Background: Sinus histiocytosis with massive lymphadenopathy (SHML) – Rosai-Dorfman disease is a well recognised, but rare cause of lymphadenopathy in the first two decades of life. Histologically is characterised by capsular fibrosis, histiocytes and plasma cells proliferation, lymphogranulocytosis. SHML is classified as class II histiocytosis (according to WHO). The disease is considered to be a disorder of immune regulation or a reaction to certain infectious factors. Clinically, radiologically and histopathologically, SHML requires differentiation with sarcoidosis, Hodgkin’s disease, Langerhans histiocytosis, granulomatous disease, lipid storage disorders and non-specific inflammations. The clinical outcome varies from spontaneous remission to diverse responses to the treatment applied. We present this case for the reason of rarity and immunophenotypic differences
from other histiocytosis.
Case report: We present a multiple organ form of SHML in a 7 year girl with massive enlargement of cervical
lymph nodes. Histopatologic examination of a lymph node revealed a proliferation of histiocytes and plasma cells, lymphophagocytosis, presence of S-100 protein, negative reaction for CD1 and HLA-DR, electron microscopy negative for the Birbeck granules. The bone examination showed numerous osteolytic loss in the upper and lower limb bones with silmilar histopatologic changes. Due to multiple organ involvement treatment with prednisolone and vinblastine was instituted to obtain a reduction in lymphadenopathy and regression of bony ailments. The patient completed therapy two years ago with no evidence of disease.
Conclusions: Sinus histiocytosis with massive lymphadenopathy (SHML) – represents a rare cause of lymphadenopathy and should be considered in the differential diagnosis expecially with LCH.

Keywords: Rosai-Dorfman disease, Histiocytosis, children, immune dysfunction