Lesch-Nyhan Syndrome

Key Features

• X-linked recessive disorder

• Manifests in boys with spasticity, dystonia, and self-mutilating behaviors

• Urinary uric acid to creatinine ratio or urine succinylpurines are useful screening tests.

Clinical Findings

• Complete deficiency is characterized by CNS dysfunction and purine overproduction with hyperuricemia and hyperuricosuria

• Choreoathetosis

• Spasticity

• Compulsive, mutilating lip and finger biting

• Gouty arthritis

• Urate ureterolithiasis

Diagnosis

• Elevated uric acid-creatinine ratio in urine

• Demonstration of enzyme deficiency in red blood cells or fibroblasts or by molecular analysis

Treatment

• Hyperhydration and alkalinization are essential to prevent kidney stones and urate nephropathy

• Allopurinol and probenecid may be given to reduce hyperuricemia and prevent gout but do not affect the neurologic status

• Physical restraints are often more effective than neurologic medications for automutilation