Niemann-Pick type B in adulthood

Niemann-Pick disease (NPD) is a rare group of autosomal recessive disorders associated with intracellular deposition of sphingomyelin. NPD type B is a milder form, generally later in onset, with a good prognosis for survival into adulthood and usually with no neurological abnormalities. The authors describe the case of a 52-year-old man who presented with unexplained pancytopenia and splenomegaly. He was admitted to emergency splenectomy due to pathological splenic rupture. The histological findings showed diffuse histiocytosis, suggesting lysosomal storage disease. The NPD was confirmed when residual activity of acid sphingomyelinase in peripheral blood leucocytes and cultured skin fibroblasts was detected. Besides lipid abnormalities, the patient also had lipid interstitial pneumonia. There is no treatment for NPD. Management is based on surveillance and supportive care. The patient has reached the sixth decade of life with no symptoms and, despite the pneumonia and splenectomy, he still has a fairly healthy life.