Familial lipoprotein lipase deficiency is a group of rare genetic disorders in which a person lacks a protein needed to break down fat molecules. The disorder causes large amounts of fat to build up in the blood.

Type I hyperlipoproteinemia; Familial chylomicronemia

Familial lipoprotein lipase deficiency is usually caused by a defective gene that is passed down through families.

Persons with this condition lack an enzyme called lipoprotein lipase. Without this enzyme, the body cannot break down fat from digested food. Fat particles called chylomicrons build up in the blood.

Risk factors include a family history of lipoprotein lipase deficiency.

The disorder affects about 1 out of 1,000,000 people. The condition is usually first seen during infancy or childhood.

• Abdominal pain (may appear as colic in infancy)
• Loss of appetite
• Nausea
• Pain in the muscles and bones (musculoskeletal pain)
• Vomiting

Signs of this condition include:

• Enlarged liver
• Failure to thrive in infancy
• Fatty deposits in the skin (xanthomas)
• High triglyceride levels in the blood
• Pale retinas and white-colored blood vessels in the retinas
• Pancreatitis that keeps returning
• Yellowing of the eyes and skin (jaundice)

Blood tests will be done to check cholesterol and triglyceride levels. Rarely, a special blood test may be done after you are given blood thinners through a vein. This test looks for lipoprotein lipase activity in your blood.

Genetic tests may be done, including one for apolipoprotein CII deficiency.

Treatment aims to control the symptoms and blood triglyceride levels with a very low-fat diet. You should eat no more than 20 grams of fat per day to prevent the symptoms from coming back.

Twenty grams of fat is equal to one of the following:

• 2 8-ounce glasses of whole milk
• 4 teaspoons of margarine
• 4-ounce serving of meat

The average American diet has a fat content of up to 45% of total calories. Fat-soluble vitamins A, D, E, and K and mineral supplements are recommended for people who eat a very low-fat diet. Dietary counseling may be helpful for patients who are trying to stick to a strict diet and still get enough calories and nutrients.

Pancreatitis that is related to lipoprotein lipase deficiency responds to treatments for that disorder.

Persons with this condition who follow a very low-fat diet may live into adulthood.

Pancreatitis and recurrent episodes of abdominal pain may develop.

Xanthomas are not usually painful unless they are rubbed a lot.

Call your health care provider for screening if someone in your family has lipoprotein lipase deficiency. Genetic counseling is recommended for anyone with a family history of this disease.

There is no known prevention for this rare, inherited disorder. Awareness of risks may allow early detection. Following a very low-fat diet can dramatically improve the symptoms of this disease.

Gennest J, Libby P. Lipoprotein disorders and cardiovascular disease. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 47.

Semenkovich CF. Disorders of lipid metabolism. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier;2007: chap 217.