What is Lesch-Nyhan syndrome?
Lesch-Nyhan syndrome (LNS) is a rare, inherited disorder caused by a deficiency of the enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT). LNS is an X-linked recessive disease carried by the female parent and passed on to a male child. LNS is present at birth in males. The lack of HPRT causes a build-up of uric acid in all body fluids, and leads to symptoms such as:
- Severe gout
- Poor muscle control
- Moderate developmental disabilities, which appear in the first year of life
A striking feature of LNS is self-mutilating behaviors—characterized by lip and finger biting—that begin in the second year of life. Abnormally high uric acid levels can cause sodium urate crystals to form in the joints, kidneys, central nervous system, and other tissues of the body, leading to gout-like swelling in the joints and severe kidney problems. Neurological symptoms include:
- Facial grimacing
- Involuntary writhing
- Repetitive movements of the arms and legs similar to Huntington's disease
Because a lack of HPRT causes the body to poorly utilize vitamin B12, some males may develop a rare disorder called megaloblastic anemia.
Treatment for LNS is symptomatic. Gout can be treated with allopurinol to control excessive amounts of uric acid. Kidney stones may be treated with lithotripsy, a technique for breaking up kidney stones using shock waves or laser beams. There is no standard treatment for the neurological symptoms of LNS. Some may be relieved with the drugs carbidopa/levodopa, diazepam, phenobarbital, or haloperidol.
How can I or my loved one help improve care for people with Lesch-Nyhan syndrome?
Consider participating in a clinical trial so clinicians and scientists can learn more about LNS and related disorders. Clinical research uses human volunteers to help researchers learn more about a disorder and perhaps find better ways to safely detect, treat, or prevent disease.
All types of volunteers are needed—those who are healthy or may have an illness or disease—of all different ages, sexes, races, and ethnicities to ensure that study results apply to as many people as possible, and that treatments will be safe and effective for everyone who will use them.
Where can I find more information about Lesch-Nyhan syndrome?
Information may be available from the following resources:
National Organization for Rare Disorders (NORD)
Phone: 203-744-0100; 800-999-6673; 844-259-7178 Spanish
Purine Research Society