OBJECTIVETo study the clinical features of two families with distal renal tubular acidosis (dRTA) and mutations in the pathogenic gene SLC4A1.

METHODSFamily investigation, medical history collection, and measurement of biochemical parameters were performed to analyze the clinical phenotype and genetic characteristics of dRTA. Direct sequencing was used to detect SLC4A1 gene mutations.

RESULTSThree patients in these two families (two of them were mother and son) were diagnosed with dRTA with typical clinical features, including short stature, metabolic acidosis, alkaline urine, hypokalemia, and nephrocalcinosis. SLC4A1 gene analysis showed that all the three patients had a pathogenic missense mutation R589H (c.1766G>A). The child in family 1 had a de novo mutation of SLC4A1, and the child in family 2 had an SLC4A1 gene mutation inherited from the mother, which met the characteristic of autosomal dominant inheritance.

CONCLUSIONSThis study reports the R589H mutation in SLC4A1 gene in families with hereditary dRTA for the first time in China. Clinical physicians should perform gene detection for patients suspected of hereditary dRTA to improve the diagnosis and treatment of this disease.