What is Niemann-Pick Disease?

A group of inherited diseases that affect how lipids collect in the spleen, liver, and brain cells, Niemann-Pick disease can give off different symptoms and affect people at different stages of life. There are four forms to this condition; typically called Type A, B, C, and D.

Type A and B

Type A and B occur when there isn't any acid sphingomyelinase, or ASM, in the body. It can lead to cell death. Type A has a higher predominance in Eastern European Jewish people.

Type C and D

Type C is caused by not being able to break down lipids and cholesterol. It is most common in Spanish descendents. Type D has defects that interfere with cholesterol movement in the brain cells and may be a variant of Type C. It is found in the French Canadian people of Yarmouth County.

Type A Symptoms

Signs of a Type A include a cherry red spot in the eye, loss of early motor skills, feeding difficulties, and belly swelling in three to six months.

Type B Symptoms

The Type B type has milder symptoms. They may have belly swelling and repeated respiratory infections but usually do not have a loss of motor skills or nervous system involvement.

Type C&D Symptoms

Type C and Type D have similar symptoms. These include an enlarged spleen or liver, difficulty in moving the limbs, seizures, tremors, slurred or irregular speech, loss of muscle tone that is sudden, learning difficulties, intellectual decline, jaundice, unsteadiness, clumsiness, walking problems, and trouble moving eyes up and down.

Diagnosis

ASM can be measured to determine how much is in the white blood cells, which is a good test for Type A and Type B cases. Or DNA testing is possible for these types. Type C and D may take skin biopsies to diagnose. Other tests that may occur are slit-lamp eye exams, liver biopsy, bone marrow aspiration, or a sphingomyelinase assay.

Treatment

There is no treatment for Type A but Type B may have gene therapy, enzyme replacement therapy, or bone marrow transplantation. Type C is treated from miglustat while Type D has no specific therapy. Diet control is recommended, low-cholesterol and healthy.

Type A is severe and can lead to death by age 3. Possible complications from any of the types of Neimann-Pick disease include death, deafness, blindness, and brain damage.

Source: A.D.A.M.