Lipid storage disorders Support Group

Lipid storage disorders (or lipidoses) are a group of inherited metabolic disorders in which harmful amounts lipids (fats) accumulate in some of the body’s cells and tissues. People with these disorders either do not produce enough of one of the enzymes needed to metabolize lipids or they produce enzymes that do not work properly. Over time, this excessive storage of fats can cause permanent cellular and tissue damage, particularly in the brain, peripheral nervous system, liver, spleen and bone marrow.

Gaucher disease is the most common of the lipid storage diseases. It is caused by a deficiency of the enzyme glucocerebrosidase. Fatty material can collect in the spleen, liver, kidneys, lungs, brain, and bone marrow. Symptoms may include enlarged spleen and liver, liver malfunction, skeletal disorders and bone lesions that may cause pain, severe neurologic complications, swelling of lymph nodes and (occasionally) adjacent joints, distended abdomen, a brownish tint to the skin, anemia, low blood platelets, and yellow spots in the eyes. Persons affected most seriously may also be more susceptible to infection. The disease affects males and females equally.

Niemann-Pick disease is actually a group of autosomal recessive disorders caused by an accumulation of fat and cholesterol in cells of the liver, spleen, bone marrow, lungs, and, in some patients, brain. Neurological complications may include ataxia, eye paralysis, brain degeneration, learning problems, spasticity, feeding and swallowing difficulties, slurred speech, loss of muscle tone, hypersensitivity to touch, and some corneal clouding. A characteristic cherry-red halo develops around the center of the retina in 50 % of patients.

Fabry disease, also known as alpha-galactosidase-A deficiency, causes a buildup of fatty material in the autonomic nervous system, eyes, kidneys, and cardiovascular system. Fabry disease is the only x-linked lipid storage disease. Males are primarily affected although a milder form is common in females, some of whom may have severe manifestations similar to those seen in affected males. Onset of symptoms is usually during childhood or adolescence. Neurological symptoms include burning pain in the arms and legs, which worsens in hot weather or following exercise, and the buildup of excess material in the clear layers of the cornea (resulting in clouding but no change in vision). Fatty storage in blood vessel walls may impair circulation, putting the patient at risk for stroke or heart attack. Other symptoms include heart enlargement, progressive kidney impairment leading to renal failure, gastrointestinal difficulties, decreased sweating, and fever. Angiokeratomas (small, non-cancerous, reddish-purple elevated spots on the skin) may develop on the lower part of the trunk of the body and become more numerous with age.

Farber’s disease, also known as Farber’s lipogranulomatosis or ceramidase deficiency, describes a group of rare autosomal recessive disorders that cause an accumulation of fatty material in the joints, tissues, and central nervous system. The disorder affects both males and females. Disease onset is typically in early infancy but may occur later in life. Children who have the classic form of Farber’s disease develop neurological symptoms within the first few weeks of life. These symptoms may include moderately impaired mental ability and problems with swallowing. The liver, heart, and kidneys may also be affected. Other symptoms may include vomiting, arthritis, swollen lymph nodes, swollen joints, joint contractures (chronic shortening of muscles or tendons around joints), hoarseness, and xanthemas which thicken around joints as the disease progresses. Patients with breathing difficulty may require insertion of a breathing tube. Most children with the disease die by age 2, usually from lung disease. In one of the most severe forms of the disease, an enlarged liver and spleen (hepatosplenomegaly) can be diagnosed soon after birth. Children born with this form of the disease usually die within 6 months.

Krabbé disease (also known as globoid cell leukodystrophy and galactosylceramide lipidosis) is an autosomal recessive disorder caused by deficiency of the enzyme galactosylceramidase. The disease most often affects infants, with onset before age 6 months, but can occur in adolescence or adulthood. The buildup of undigested fats affects the growth of the nerve’s protective myelin sheath and causes severe degeneration of mental and motor skills. Other symptoms include muscle weakness, hypertonia (reduced ability of a muscle to stretch), myoclonic seizures (sudden, shock-like contractions of the limbs), spasticity, irritability, unexplained fever, deafness, optic atrophy and blindness, paralysis, and difficulty when swallowing. Prolonged weight loss may also occur. The disease may be diagnosed by its characteristic grouping of certain cells, nerve demyelination and degeneration, and destruction of brain cells. In infants, the disease is generally fatal before age 2. Patients with a later onset form of the disease have a milder course of the disease and live significantly longer. No specific treatment for Krabbé disease has been developed, although early bone marrow transplantation may help some patients.

Metachromatic leukodystrophy, or MLD, is a group of disorders marked by storage buildup in the white matter of the central nervous system and in the peripheral nerves and to some extent in the kidneys. Similar to Krabbé disease, MLD affects the myelin that covers and protects the nerves. This autosomal recessive disorder is caused by a deficiency of the enzyme arylsufatase A. Both males and females are affected by this disorder.

Wolman’s disease, also known as acid lipase deficiency, is a severe lipid storage disease that is usually fatal by age 1. This autosomal recessive disorder is marked by accumulation of cholesteryl esters (normally a transport form of cholesterol) and triglycerides (a chemical form in which fats exist in the body) that can build up significantly and cause damage in the cells and tissues. Both males and females are affected by this severe disorder. Infants are normal and active at birth but quickly develop progressive mental deterioration, enlarged liver and grossly enlarged spleen, distended abdomen, gastrointestinal problems including steatorrhea (excessive amounts of fats in the stools), jaundice, anemia, vomiting, and calcium deposits in the adrenal glands, causing them to harden.

Currently there is no specific treatment available for most of the lipid storage disorders but highly effective enzyme replacement therapy is available for patients with type 1 Gaucher disease, some patients with type 3 Gaucher disease, and Fabry disease. Ongoing research is in place to provide enzyme replacement for other lipidoses as well as gene therapy. Patients with anemia may require blood transfusions. In some patients, the enlarged spleen must be removed to improve cardiopulmonary function. The drugs phenytoin and carbamazepine may be prescribed to help treat pain (including bone pain) for patients with Fabry disease. Restricting one’s diet does not prevent lipid buildup in cells and tissues.