Niemann-Pick disease type B revealed by sea blue histiocytes: A case report

Niemann-Pick type B is a rare autosomal recessive syndrome storage disease. It is due to a total or partial deficiency in sphingomyelinase, causing a buildup of sphingomyelin in reticulo-endothelial cellular system. The diagnosis is based on examining enzyme deficiency. The clinical context and careful examination of the blood and bone marrow may therefore be a key step in the diagnostic process. In this respect, we mention a rare case of a young woman aged 20 years; the latter suffers from thrombocytopenia associated with splenomegaly that justified realization of myelogram which discovered, after staining with May-Grunwald-Giemsa (MGG), the presence of numerous histiocytes blue infiltrating the bone marrow. With these clinical and cytological data in mind, the diagnosis of Niemann-Pick disease type B is raised. This is made valid by measuring the enzymatic activity of acid sphingomyelinase lysosomal which is decreased. (C) 2013 Elsevier Masson SAS. All rights reserved.