A Case of Idiopathic Renal Hypouricemia with SLC22A12 Gene Mutation Showing General Weakness and Incidental Renal Stone
10.3339/jkspn.2021.25.1.44
- Author:
Jin Woon JOUNG
1
;
Young Wha SONG
;
Jong Dae KIM
;
Eun Jung CHEON
Author Information
1. Department of Pediatrics, Konyang University College of Medicine, Daejeon, Korea
- Publication Type:3
- From:Childhood Kidney Diseases
2021;25(1):44-48
- CountryRepublic of Korea
- Language:English
-
Abstract:
Idiopathic renal hypouricemia (iRHUC) is a rare hereditary disease caused by a defect in urate handling of renal tubules. Type 1 renal hypouricemia (RHUC1) is diagnosed with confirmation of a mutation in SLC22A12 gene which encodes a renal urate-anion exchanger (URAT1). The majority of iRHUC patients are asymptomatic, especially during childhood, and thus many cases go undiagnosed or they are diagnosed late in older age with complications of hematuria, renal stones, or acute kidney injury (AKI). We report a case of a 7-year-old boy with subtle symptoms such as general weakness and dizziness and revealed hypouricemia and incidental nephrolithiasis. Homozygous mutations were detected in the SLC22A12(c.774G>A) by molecular analysis. The present case suggests that fractional excretion of uric acid (FEUA) screening could be better followed by the coincidental discovery of hypouricemia, to prevent conflicting complications of iRHUC, even with normal urine uric acid to creatinine ratio (UUA/UCr), and sequential genetic analysis if needed.
