Abstract:

Objective To analyze the clinical features and HPRT1 gene variation characteristics of Lesch-Nyhan syndrome in children and to improve the understanding for the disease. Methods The clinical manifestations, laboratory examination and genetic test results of 8 children diagnosed with Lesch-Nyhan syndrome and followed up from July 2015 to November 2019 were retrospectively analyzed, and the clinical characteristics and HPRT1 gene variation characteristics of the children were analyzed and summarized. Results All the 8 patients were male, and the onset of disease was from 3 months to 11 months old. The patients mainly visited because of developmental retardation, accompanied by pyramidal and extrapyramidal symptoms. Four patients had self-mutilation behavior before seeing a doctor, another 4 patients did not have at present, and the blood uric acid increased in different degrees. Six variations (c.609+5G>A, exon 2-3 del, c.131G>A, exon7-8 del, c.384+2T>A and c.212G>A) were detected in their HPRT1 gene. After oral sodium bicarbonate, allopurinol and baclofen and home-based rehabilitation, the symptoms of brain injury were relieved in 5 patients. One patient died of asphyxia, 1 died of pulmonary infection, and 1 was aggravated without regular medication and reexamination. Conclusions The clinical symptoms of Lesch Nyhan syndrome are complex. The main characteristics are nervous system dysfunction, self-mutilation behavior and hyperuricemia. Gene sequencing is the key to diagnosis. Symptomatic treatment can improve symptoms of the patients.

Key words: Lesch Nyhan syndrome, hypoxanthine guanine phosphoribosyltransferase, self- mutilation behavior, hyperuricemia, HPRT1 gene