What is Niemann-Pick Disease?
Niemann-Pick disease (NP) refers to a group of inherited metabolic disorders known as lipid storage diseases. Lipids (fatty materials such as waxes, fatty acids, oils, and cholesterol) and proteins are usually broken down into smaller components to provide energy for the body. In Niemann-Pick disease, harmful quantities of lipids accumulate in the spleen, liver, lungs, bone marrow, and the brain. Symptoms may include lack of muscle coordination, brain degeneration, eye paralysis, learning problems, loss of muscle tone, increased sensitivity to touch, spasticity, feeding and swallowing difficulties, slurred speech, and an enlarged liver and spleen. There may be clouding of the cornea and a characteristic cherry-red halo develops around the center of the retina. The disease has 4 related types. Type A, the most severe form, occurs in early infancy. It is characterized by an enlarged liver and spleen, swollen lymph nodes, and profound brain damage by six months of age. Children with this type rarely live beyond 18 months. Type B involves an enlarged liver and spleen, which usually occurs in the pre-teen years. The brain is not affected. In types A and B, insufficient activity of an enzyme called sphingomyelinase causes the build up of toxic amounts of sphingomyelin, a fatty substance present in every cell of the body. Types C and D may appear early in life or develop in the teen or adult years. Affected individuals have only moderate enlargement of the spleen and liver, but brain damage may be extensive and cause an inability to look up and down, difficulty in walking and swallowing, and progressive loss of vision and hearing. Types C and D are characterized by a defect that disrupts the transport of cholesterol between brain cells. Type D usually occurs in people with an ancestral background in Nova Scotia. Types C and D are caused by a lack of the NPC1 or NPC 2 proteins.
Is there any treatment?
There is currently no cure for Niemann-Pick disease. Children usually die from infection or progressive neurological loss. There is currently no effective treatment for persons with type A. Bone marrow transplantation has been attempted in a few patients with type B, and encouraging results have been reported. The development of enzyme replacement and gene therapies might also be helpful for those with type B. Individuals with types C and D are frequently placed on a low-cholesterol diet and/or cholesterol lowering drugs, but research has not shown these interventions to change the abnormal cholesterol metabolism or halt disease progression..
What is the prognosis?
Infants with type A die in infancy. Children with Type B may live a comparatively long time, but may require supplemental oxygen because of lung impairment. The life expectancy of persons with types C and D varies: some individuals die in childhood while others, who appear to be less severely affected, can live into adulthood.
What research is being done?
The National Institute of Neurological Disorders and Stroke (NINDS), a part of the National Institutes of Health (NIH), conducts research about Niemann-Pick disease in laboratories at the NIH and also supports additional research through grants to major research institutions across the country. Investigators at the NINDS have identified two different genes that, when defective, contribute to Niemann-Pick disease types C and D.
Ara Parseghian Medical Research Foundation (For Niemann-Pick Type C Disease)
National Niemann-Pick Disease Foundation, Inc.
National Tay-Sachs and Allied Diseases Association
Source: National Institutes of Health; National Institute of Neurological Disorders and Stroke
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 10/6/2011...#6059