THIRD EDITION
Factsheet
Condition:
Lesch-Nyhan syndrome
Inheritance:
X-linked recessive
Genetic Etiology:
Mutation in HPRT1 gene, encoding hypoxanthine-guanine phosphoribosyltransferase.
Frequency:
1/380,000
Clinical features:
Affected males present in infancy with hypotonia and developmental delay. There is a progressive motor disorder involving both pyramidal and extrapyramidal components. There is compulsive self-injurious behavior and deposition of uric acid in joints and uric acid calculi in the urinary tract. Milder forms may present with neurological dysfunction or hyperuricemia and renal dysfunction.
Management:
Allopurinol to block conversion of hypoxanthine and xanthine to uric acid; supportive care.
Genetic counseling:
Based on X-linked recessive inheritance. Molecular genetic testing is available.