A lysosomal storage disease due to sphingomyelin accumulation in the reticuloendothelial system; there are five types distinguished by age of onset, amount of central nervous system involvement, and degree of enzyme deficiency. At least some types are characterized by foamy reticular cells containing phospholipids which infiltrate the liver, spleen, lungs, lymph nodes, and bone marrow.Types A and B occur when acid sphingomyelinase (ASM) is not properly produced in the body, specifically in the white blood cells. Type C is primarily concerned with the body’s inability to efficiently remove excess cholesterol and other lipids. Without proper breakdown, cholesterol builds up in the spleen and liver, and excessive amounts of other fats accumulate in the brain. Type D occurs when the body cannot properly move cholesterol between cells of the brain, and is believed to be a variant of type C. Type E is a rare type of Niemann-Pick disease that occurs in adults. Little is known about this type. This disease mainly causes swollen lymph nodes, brain damage, lung disease, respiratory infections, tremors, neurological problems etc.
No specific treatment is known for type A, but symptoms are treated. In adult patients with type B, physicians try to keep cholesterol levels down to normal levels. If statins are used, they monitor liver function. If the spleen is enlarged and platelet levels low, acute episodes of bleeding may require transfusions of blood products. If they have symptoms of interstitial lung disease, they may need oxygen. Anecdotally, organ transplant has been attempted with limited success. Future prospects include enzyme replacement and gene therapy. Bone marrow transplant has been tried for type B.Results of a survey shows the extrapolation of Prevalence Rate of Niemann-Pick disease type C2 in India is 7,100 for the estimated total population of 10,65,07,06,072.Investigators at the NINDS have identified two different genes that, when defective, contribute to Niemann-Pick disease type C. NINDS scientists are studying the mechanisms by which lipids accumulating in these storage diseases causes harm to the body. Additional research studies hope to identify biomarkers (signs that may indicate risk of a disease and improve diagnosis) for the lipid storage disorders.