A type of sphingolipidosis that is often caused by a deficiency in sphingomyelinase resulting in the accumulation of sphingomyelin in brain and erythrocytes, and thereby leads to CNS damage, thrombocytopenia, spasticity, ataxia, and organ enlargement (particularly hepatosplenomegaly)
Sphingolipidosis is a collective term for the various metabolic disorders due to an abnormal sphingolipid metabolism. One of them is the Niemann-Pick disease. This condition is characterized by a buildup of sphingomyelin in the lysosomes of the brain cells and erythrocytes. This is often due to a deficiency of a functional sphingomyelinase. Sphingomyelinase is a hydrolase enzyme that is essential in sphingolipid metabolism. In particular, it breaks down the sphingomyelin into phosphocholine and ceramide.
Niemann-Pick disease may be caused by a mutation in SMPD1 gene. This affects the production of a functional sphingomyelinase, and accounts for Niemann-Pick disease types A and B. Mutation in NPC1 or NPC2 gene affects the production of a protein involved in the transport of lipids. This accounts for the Niemann-Pick disease type C. Niemann-Pick disease is hereditary and is passed on to offspring as an autosomal recessive trait.
The main symptoms of Niemann-Pick disease are hepatosplenomegaly, thrombocytopenia, seizures, mental retardation, spasticity, dysarthria, and ataxia (unsteady gait). The condition may be fatal at early childhood though some individuals may live well into adulthood (in benign type).
The name is derived from Albert Niemann and Ludwig Pick who described the condition in 1914 and in 1930s, respectively.
- Niemann disease
- sphingomyelin lipidosis