Lesch-Nyhan Syndrome

Lesch-Nyhan syndrome is a genetic disorder. It affects the metabolism of purines in the body. Purines are protein molecules that are important for the metabolism of RNA and DNA, which make up our genetic codes. Lesch-Nyhan syndrome is characterized by uric acid build-up, neurologic disability, and behavioral problems, including self-injury. This disease, which mainly affects men, is rare.

  • Causes

    Lesch-Nyhan syndrome is caused by a mutation or change in a gene. This change results in the absence of the enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT). HPRT is needed to metabolize uric acid. Without this enzyme, uric acid builds up in the central nervous system, kidneys, and other areas of the body.

    This gene mutation occurs on the X chromosome. It can either be a new mutation in the affected person or inherited from the person's mother, who is a carrier.

  • Definition

    Lesch-Nyhan syndrome is a genetic disorder. It affects the metabolism of purines in the body. Purines are protein molecules that are important for the metabolism of RNA and DNA, which make up our genetic codes. Lesch-Nyhan syndrome is characterized by uric acid build-up, neurologic disability,
    and
    behavioral problems, including
    self-injury. This disease, which mainly affects men, is rare.

  • Diagnosis

    The doctor will ask about symptoms, behavior traits, and medical history. A physical exam will be done.

    Your bodily fluids may be tested. This can be done with blood tests.

  • Prevention

    There are no guidelines to prevent Lesch-Nyhan syndrome. If you have a family history of this condition, you can talk to a genetic counselor when deciding whether to have children.

  • Risk Factors

    Factors that increase your chances of developing Lesch-Nyhan syndrome include:

    • Sex: male
    • Having male family members on the mother's side of the family with Lesch-Nyhan syndrome

  • Symptoms


    The first symptom of Lesch-Nyhan syndrome
    may be
    orange-colored crystal-like deposits in the diaper. This may occur in children as young as three months. These deposits are caused by increased uric acid in the urine. Other symptoms include:

    • Irritability

    • Nervous system impairment:

      • 4 to 6 months—lack of muscle tone and inability to lift the head
      • 6 months—unusual arching of the back
      • 9 months—inability to crawl or stand
      • 12 months—inability to walk
      • 12+ months—spasms of the limbs and facial muscles
    • Blood in the urine
    • Pain and swelling of joints
    • Difficulty swallowing



    • Behavioral problems and self injury—occurs in all cases
    Uric Acid Deposits in Joint
    uric acid toe
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  • Treatment

    There is no treatment to cure Lesch-Nyhan. However,
    good hydration and
    certain medications may help to alleviate some of its symptoms. For example:

    With treatment, the average life expectancy is early- to mid-20s. There may be an increased risk of sudden death due to respiratory causes. However, many patients live longer with good medical and psychological care.