Lysosomal storage disorders are caused by defects in enzymes located in the lysosome, a part of the body’s cells. Normally these enzymes work to break down certain complex carbohydrates (sugars).
If your child has a lysosomal storage disorder, it means certain enzymes are missing or do not work the way they should. If the substances cannot be broken down, it can lead to cell damage and eventually damage the organs in the body.
There are over 50 different types of lysosomal storage disorders. The most common types include:
- Gaucher disease. This disorder affects the spleen and bones.
- Hunter syndrome. This disorder causes permanent, progressive damage to organs and affects appearance, mental development and physical abilities.
- Hurler syndrome. This disorder causes problems with hearing, joints and potentially the heart.
- Fabry disease. This disorder affects the heart, kidneys and skin.
- Maroteaux-Lamy syndrome. This progressive condition causes many tissues and organs to enlarge.
- Morquio syndrome. This disorder affects the development of bones, including the spine.
- Pompe disease. This disorder affects the heart, liver and muscle tissue.
Lysosomal storage disorders are inherited, meaning your child received the gene from one or both parents before birth.
The symptoms of lysosomal storage disorders vary depending on the specific disorder. They may include:
- Anemia
- Breathing difficulties
- Excessive bleeding or bruising
- Facial or other bone abnormalities
- Hyperactivity or other behavioral problems
- Intellectual and/or physical developmental delay
- Pain and stiffness in the joints
- Seizures
- Enlarged abdomen due to enlarged spleen or liver
- Vision and hearing problems
Diagnosis of Lysosomal Storage Disorders
Your child's doctor may suspect a lysosomal storage disorder if he or she sees a pattern of symptoms. Further testing of the blood, urine and tissue for enzyme deficiencies can be used to help diagnose a lysosomal disorder.
Genetic testing may also be used to help determine your risk of passing on a particular gene mutation to future children. Prenatal genetic testing, done via amniocentesis and chorionic villus sampling, can be used to help diagnose lysosomal storage disorders during pregnancy. During amniocentesis, a hollow needle is inserted into the uterus to obtain a sample of the amniotic fluid. Chorionic villus sampling involves taking a tiny tissue sample from the fetal portion of the placenta. Each of these procedures involves some potential risk to the fetus and should be discussed with both a geneticist and OB/GYN before a decision is made to pursue such testing.
Treatments
Treatments
There is no cure for lysosomal storage disorders. However, treatment is available to help your child cope with various symptoms.
The most common treatment option is enzyme replacement therapy using periodic intravenous (IV) infusions. Treatment usually takes about four to five hours and is given every one to two weeks based on your child’s prescription and recommended treatment schedule.
In certain conditions, bone marrow transplantation may also be an option to slow disease progression and is generally used in conjunction with enzyme replacement therapy to help achieve the best outcome. The bone marrow may be taken from your child’s own body, or it may be taken from a healthy donor match. During the procedure, stem cells from the bone marrow are passed into your child’s body through a central line (tube placed in a large vein near the heart to help deliver treatment). The process can take anywhere from half an hour to several hours and will not be painful.
Key Points to Remember
Key Points to Remember
- Lysosomal storage disorders affect enzymes that normally break down certain complex carbohydrates (sugars).
- There is no cure for lysosomal disorders, but enzyme replacement therapy may help reduce symptoms.
- Genetic testing, including prenatal genetic testing, may help determine if a future or unborn child is at risk for a lysosomal storage disorder.
Support Services & Resources
Support Services & Resources
Visit the following websites to find support and information related to lysosomal storage disorders.
Riley at IU Health offers a broad range of supportive services to make life better for families who choose us for their children's care.
This online resource from the U.S. National Library of Medicine provides more information on Gaucher disease.
Learn more about the diagnosis and treatment of Hunter syndrome (mucopolysaccharidosis type II).
Read more about Hurler syndrome, also called mucopolysaccharidosis type I.
Learn more about how Fabry disease is diagnosed and managed.
Find more information about Maroteaux-Lamy syndrome, also called mucopolysaccharidosis type VI.
Morquio syndrome is also called mucopolysaccharidosis type IV. Learn more about this syndrome.
Learn more about the diagnosis and treatment of Pompe disease.
This nonprofit support organization offers support and programs for people and families with Fabry disease.
This website offers support, information and research for people with Gaucher disease.
This website offers education, support and information about mucopolysaccharidosis (MPS) and related lysosomal storage diseases.