Abstract:

Lesch-Nyhan syndrome is a rare X-linked recessive genetic disease. Before the occurrence of self-injury, it could be misdiagnosed as cerebral palsy. The proband, male, 8 years and 7 months old, was admitted to the clinic due to over 8 years of developmental retardation and abnormal muscle tone. Multiple blood biochemical tests showed that uric acid was increased. Genetic analysis results confirmed that the patient had c.200 _ 201delTG variation of HPRT1 gene, which was rated as a suspected pathogenic variation by ACMG. Sanger sequencing confirmed that the variation was inherited from the mother and was an unreported new variation, thus the child was diagnosed with HPRT1 gene-associated Lesch-Nyhan syndrome. After oral allopurinol tablets and sodium bicarbonate tablets for 6 months, the level of uric acid decreased significantly, and there was no self-injury behavior. In patients with unexplained cerebral palsy, genetic examination should be performed as early as possible to help early diagnosis and genetic counseling.

Key words: HPRT1 gene, Lesch-Nyhan syndrome, clinical manifestations, gene variant, child