To investigate the clinical and genetic characteristics, pathogenesis and treatment strategy of congenital nephrogenic diabetes insipidus(CNDI)combined with hyperuricemia.

The clinical manifestations and laboratory data of an infant patient diagnosed as CNDI with hyperuricemia and his family members were collected and retrospectively analyzed. Whole exome sequencing(WES)was applied to detect the proband′s genome variation of each exon and suspected variants of AVPR2 and ABCG2 were verified by PCR-Sanger sequencing of members from his pedigree. Furthermore, we retrospectively collected the serum uric acid levels of patients(≤14-year-old) with CNDI in the First Affiliated Hospital of Zhengzhou University from January 2015 to January 2022.

The proband was clinically diagnosed with CNDI and the rest of the family members had no symptoms of polydipsia or polyuria. In addition to the proband, his father was also suffered from hyperuricemia. WES showed that the proband carried a hemizygous AVPR2 gene variation(p.S331R)and a heterozygous ABCG2 gene variation(p.N308K). The former was X-linked recessive inheritance from his mother, and the latter was autosomal dominant inheritance from the father. Fraction excretion of uric acid(FEUA)of the proband and his father with hyperuricemia were 3.1% and 2.7%, respectively. Twelve children(≤14-year-old)were diagnosed with CNDI from the respective study. Among all the cases, 11 patients were male and 1 was female, ranging from 3-month to 14-year-old. Five patients were accompanied with hyperuricemia.

Children with CNDI may be complicated with hyperuricemia, and the regimen of hydrochlorothiazide combined with benzbromarone is effective. The pathogenicity of the AVPR2 gene variation(p.S331R)and ABCG2 gene variation(p.N308K)in this pedigree needs to be further studied.

Congenital renal diabetes insipidus; Hyperuricemia in children; AVPR2 gene variation; ABCG2 gene variation; Treatment