Lysosomal Acid Lipase Deficiency

Lysosomal acid lipase deficiency is a metabolic lipid storage disease. Two rare conditions may result from this deficiency (likely representing two ends of a clinical spectrum): Symptoms include an enlarged liver and spleen (hepatosplenomegaly), poor weight gain, a yellowish color of the skin and the whites of the eyes (jaundice), vomiting, diarrhea, fatty stool (steatorrhea), and poor absorption of nutrients from food (malabsorption), as well as calcium deposits in adrenal glands, anemia, liver disease (cirrhosis), and developmental delay. Infants with this form of Lysosomal acid lipase deficiency develop failure in multiple organs, and severe malnutrition. Cholesteryl ester storage disease: Less severe and starting later in life. Symptoms may include hepatosplenomegaly, liver disease (cirrhosis), and malabsorption with diarrhea, vomiting, and steatorrhea. Lysosomal acid lipase deficiency is caused by genetic changes in the LIPA gene, which provides instructions to produce the lysosomal acid lipase enzyme. When there is not enough of this enzyme, the body cannot break down certain fats and this leads to a toxic buildup of fatty substances in the body’s cells and tissues. Inheritance is autosomal recessive. Enzyme replacement therapy for both Wolman disease and cholesteryl ester storage disease is currently approved for use in the United States, European Union, and Japan.

Genetic Mutations: Lysosomal acid lipase deficiency is caused by genetic mutations, also known as pathogenic variants. Genetic mutations can be hereditary, when parents pass them down to their children, or they may occur randomly when cells are dividing. Genetic mutations may also result from contracted viruses, environmental factors, such as UV radiation from sunlight exposure, or a combination of any of these.

If you suspect you may have this disease, you may want to start collecting your family health history. Information such as other family members who have had similar symptoms, when their/your symptoms first appeared, or exposures to any potential disease-causing environmental factors should be discussed with your medical team.

Disruption in Metabolism: Lysosomal acid lipase deficiency is caused by a disruption in a person’s metabolism. Metabolism is the series of chemical reactions in our body that turns the food we eat into energy and removes toxins. Hormones and specific proteins, called enzymes, help make the right chemical reactions happen in the right order. However, genetic changes can prevent hormones or enzymes from working properly, which can lead to a disruption in metabolism such as energy not being created for the body or toxins not being removed from the body.

Impaired Lysosomal Function: This disease is caused by an impairment, or issue, in lysosomal function. Lysosomes are located inside cells and contain digestive enzymes that help break down fats, sugars, and other substances to create energy for the body. Genetic mutations can affect lysosomes such as having a missing or non-functioning digestive enzyme. This can prevent cells from properly breaking down toxins or moving them out of the cell. If toxins build up, the cell may become damaged or die. Depending on their location in the body, these damaged or dead cells may affect different organs and body systems.

Yes. It is possible for a biological parent to pass down genetic mutations that cause or increase the chances of getting this disease to their child. This is known as inheritance. Knowing whether other family members have previously had this disease, also known as family health history, can be very important information for your medical team.

There are multiple ways, or patterns, a disease can be inherited depending on the gene(s) involved. Based on GARD’s current data, this disease can be inherited in the following pattern(s):

Autosomal Recessive: Autosomal means the gene involved is located on one of the numbered chromosomes. Recessive means that a child must inherit two copies of the mutated gene, one from each biological parent, to be affected by the disease. A carrier is a person who only has one copy of the genetic mutation. A carrier usually doesn’t show any symptoms of the disease.

If both biological parents are carriers, there is a 25% chance their child inherits both copies of the mutated gene and is affected by the disease. Additionally, there is a 50% chance their child inherits only one copy of the mutated gene and is a carrier.