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.Niemann-Pick disease types A and B occur when cells in the body do not have an enzyme called acid sphingomyelinase (ASM). Type A occurs in all races and ethnicities. It is more common in the Ashkenazi (Eastern European) Jewish population. Type C occurs when the body cannot properly break down cholesterol and other fats (lipids). This leads to too much cholesterol in the liver and spleen and too much of other lipids in the brain. Type C is most common among Puerto Ricans of Spanish descent. Type D involves a defect that interferes with how cholesterol moves between brain cells. It is a variant of type C.
It causes Abdominal (belly area) swelling within 3 to 6 months, Seizures, Unsteady gait, clumsiness, walking problems, Difficulty moving limbs, Jaundice at birth. Several treatment options, including bone marrow transplants, enzyme replacement therapy, and gene therapy have been used. Research is ongoing to determine the effectiveness of such treatments. A medication called miglustat is currently used to treat type C. Miglustat is classified as an enzyme inhibitor, and works by preventing the body from producing fatty substances (in the case of type C, cholesterol) so that less of it will build up in the body. And there is no treatment for type A and D.The word 'prevalence' of Niemann-Pick disease, type C2 usually means the estimated population of people who are managing Niemann-Pick disease, type C2 at any given time (i.e. people with Niemann-Pick disease, type C2). The term 'incidence' of Niemann-Pick disease, type C2 means the annual diagnosis rate, or the number of new cases of Niemann-Pick disease, type C2 diagnosed each year (i.e. getting Niemann-Pick disease, type C2). Hence, these two statistics types can differ: a short disease like flu can have high annual incidence but low prevalence, but a life-long disease like diabetes has a low annual incidence but high prevalence.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.