Abstract: Objective　To explore the clinical and genetic variation characteristics of primary hyperaciduria typeⅠ(PH1) in children. Method　The clinical data of PH1 in 5 children were retrospectively analyzed. Results　In 5 children (3 boys; 2 girls), the age at onset ranged from 2 months to 4 years. All of the patients had refractory metabolic acidosis, hyperkalemia, hypocalcemia and other non-specific clinical manifestations, and the older children could have the specific manifestations of multiple kidney stones. Genetic tests showed that all 5 children had mutations at different sites of AGXT gene and a total of 6 mutation sites were found, in which exon 6 c.679_680del deletion mutation was in 3 children and exon 2 c.190A>T mutation was first reported. Conclusion　The clinical manifestations of PH1 are diverse, and genetic testing is helpful for early diagnosis and intervention and also delay of the progress of terminal kidney.

Key words: primary hyperoxaluria typeⅠ;　AGXT gene;　child