Lysosomal storage disorders (LSDs) are a group of rare genetic conditions that can affect various organs in the body. There are more than 70 types of LSDs, some of which have subtypes.  

Lysosomes are sac-like structures in almost every cell of the human body. Their job is to degrade (break down) and reuse cellular material. The material that should be broken down but builds up in LSDs in the lysosome is known as the substrate. The substrate may be a type of sugar or fat. 

Enzymes are types of proteins within lysosomes that can break down specific substrates. An LSD is typically caused by changes in a gene leading to not enough activity of a certain enzyme. As a result, the substrate builds up, leading to the signs and symptoms of the LSD. 

All LSDs are life lasting, progressive (worsen over time), and multisystemic (affect multiple organs). They can be serious and sometimes life-limiting. However, for many patients, their LSDs can be managed.

 

Symptoms vary across the different types of LSDs. Depending on the condition, one or many of these symptoms may occur: 

• Delays in intellectual and/or physical development 
• Mobility, vision, and/or hearing issues 
• Difficulty breathing 
• Easy bleeding or bruising 
• Enlarged organs, such as liver or spleen 
• Joint stiffness and pain 
• Bone deformities 
• Fatigue 

These are not all possible symptoms, nor do all patients have all the listed symptoms. Talk to your doctor about any symptoms that concern you. 

 

As LSDs commonly run in families, it is important for many patients to understand who else in your family (such as children, siblings, parents) may be at risk for the condition. It can be helpful to speak with a healthcare provider to discuss what genetic testing options are available and which specific test would be the most informative. 

Individuals can be diagnosed at all stages of life. Some people may find out they have an LSD because they experience certain symptoms, while others can receive a diagnosis after someone in their family has done genetic testing. In some instances, children may be diagnosed a few days after they are born as a result of newborn screening (NBS). While all babies in the United States receive newborn screening, only certain states test for specific LSDs. Talk to your healthcare provider to discuss more about NBS in your state.  

Although currently there is no cure for LSDs, treatment may help manage and alleviate symptoms for many patients. Enzyme replacement therapy (ERT) is the most common type of treatment for LSDs. It is administered to patients through intravenous (IV) infusions by trained health care providers either at a health center or at home if your doctor thinks that is proper for you. Substrate reduction therapy (SRT) is another type of treatment for some LSDs, which takes the form of an oral pill. There are also other therapies as important parts of the management, such as physical therapy or occupational therapy, that can help patients manage some symptoms. 

Talk to your doctor about if you should be considered for testing, or you are interested in starting treatment with your confirmed diagnosis.