Niemann-Pick Disease Testing

Niemann-Pick disease is a lysosomal storage disorder that is characterized by failure to thrive and enlargement of the liver and spleen (hepatosplenomegaly).

Approximately 1 in 90 persons of Ashkenazi Jewish descent are carriers for Niemann-Pick disease.

This blood test identifies four mutations associated with Niemann-Pick diseases, Type A and B. This test only analyzes mutations found in types A and B and has a detection rate of 95% for Ashkenazi Jewish individuals. There are at least five different reported subtypes:

• Type A is the infantile form that generally leads to death in early childhood.
• Type B is often called the chronic or non-neuropathic form in which affected individuals have absence of neurologic involvement and prolonged survival.
• Type C has a slower onset of symptoms and is considered the juvenile form.
• Type D appears to be isolated to a certain population in Nova Scotia.
• Type E is adult-onset Niemann-Pick. This test does not provide information about types C, D, and E.

This test has limited value for people of non-Ashkenazi Jewish ancestry, as the mutation detection rate is negligible. DNA test results must be combined with clinical information for the most accurate interpretation.