A triple heterozygous mutations in Gitelman syndrome with renal calculi.

BACKGROUND

Gitelman syndrome (GS) is a rare autosomal recessive salt-losing tubulopathy. Mutations in the gene encoding the renal thiazide-sensitive Na/Cl cotransporter in the distal renal tubule, cause GS. Identifying biallelic inactivating mutations in the gene is the most common finding in GS, while the detection of renal calculi is relatively rare.

CASE PRESENTATION

We report the case of a 33-year-old man admitted with recurrent limb weakness for six years. Laboratory tests showed hypokalemic alkalosis, hypocalciuria and renal potassium wasting; serum magnesium and aldosterone were normal, and ultrasound and computed tomography scans showed right-sided renal calculus. A hydrochlorothiazide test was performed, which showed a blunted response to hydrochlorothiazide. Next-generation sequencing identified triple mutations in , including novel splicing heterozygous mutations (c.2285+2T>C). He was administered with oral potassium chloride and spironolactone and maintained mild symptomatic hypokalemia during his follow-up.

CONCLUSIONS

The patient was diagnosed with Gitelman syndrome by genetic testing, accompanied by kidney stones. Although kidney stones are rare in Gitelman syndrome, they are not excluded as a criterion. The composition of kidney stones may be of significance for diagnosis and treatment. HIPPOKRATIA 2023, 27 (2):64-68.