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Niemann-Pick Disease


Matt Demczko

, MD, Mitochondrial Medicine, Children's Hospital of Philadelphia

Reviewed/Revised Oct 2021 | Modified Sep 2022

Niemann-Pick disease is a sphingolipidosis Sphingolipidoses Lysosomal enzymes break down macromolecules, either those from the cell itself (eg, when cellular structural components are being recycled) or those acquired outside the cell. Inherited defects... read more , an inherited disorder of metabolism, caused by deficient sphingomyelinase activity, resulting in accumulation of sphingomyelin (ceramide phosphorylcholine) in reticuloendothelial cells. Diagnosis is by DNA analysis and/or enzyme analysis of white blood cells. Bone marrow transplantation, stem cell transplantation, and enzyme replacement may be treatment options.

Children with type A have < 5% of normal sphingomyelinase activity. The disease is characterized by hepatosplenomegaly, failure to thrive, and rapidly progressive neurodegeneration. Death occurs by age 2 or 3 years.

Patients with type B have sphingomyelinase activity within 5 to 10% of normal. Type B is more variable clinically than type A. Hepatosplenomegaly and lymphadenopathy may occur. Pancytopenia is common. Most patients with type B have little or no neurologic involvement and survive into adulthood; they may be clinically indistinguishable from those with type I Gaucher disease Gaucher Disease Gaucher disease is a sphingolipidosis, an inherited disorder of metabolism, resulting from glucocerebrosidase deficiency, causing deposition of glucocerebroside and related compounds. Symptoms... read more . In severe cases of type B, progressive pulmonary infiltrates cause major complications.

Diagnosis of Niemann-Pick Disease

  • Prenatal screening

  • White blood cell sphingomyelinase assay

Both types are usually suspected by history and examination, most notably hepatosplenomegaly. Diagnosis of Niemann-Pick disease can be confirmed by DNA analysis and/or sphingomyelinase assay on white blood cells and can be made prenatally by using amniocentesis or chorionic villus sampling. DNA tests also can be done to diagnose carriers. (Also see testing for suspected inherited disorders of metabolism Initial testing Most inherited disorders of metabolism (inborn errors of metabolism) are rare, and therefore their diagnosis requires a high index of suspicion. Timely diagnosis leads to early treatment and... read more .)

Treatment of Niemann-Pick Disease

  • Possible bone marrow transplantation, stem cell transplantation, and enzyme replacement

Bone marrow transplantation, stem cell transplantation, and enzyme replacement are under investigation as potential treatment options.

More Information

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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