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Updated: Nov 17, 2025

Determining the Likelihood of Variant Pathogenicity Using Amino Acid-level Signal-to-Noise Analysis of Genetic Variation
Published on: January 16, 2019
Gitelman Syndrome: A Rare Case of Hypokalaemia and a Novel Mutation
Clara Matos1, Fábio Correia1, Inês Nunes da Silva1
1Department of Internal Medicine, Hospital Professor Doutor Fernando Fonseca, Amadora, Portugal.
Abstract:
Gitelman syndrome (GS) is a hereditary renal tubulopathy caused by mutations in the SLC12A3 gene which encodes the thiazide-sensitive apical sodium-chloride cotransporter. GS is characterized by hypokalaemia, hypomagnesaemia and metabolic alkalosis. Treatment is based on potassium and magnesium replacement ad eternum. We present the case of a young man with palpitations and persistent hypokalaemia, who was diagnosed with GS. Genetic testing revealed 2 mutations in the gene SLC12A3 of combined heterozygosity, both considered pathological. Interestingly, 1 of these mutations was not yet described in the literature or in the reviewed databases. We also discuss the clinical approach and the specificities of managing this rare hereditary renal tubulopathy..
Learning Points:
Gitelman syndrome is a rare cause of persistent hypokalaemia.A definitive diagnosis is determined by the identification of mutations in the SLC12A3 gene.Management consists of chronic potassium and magnesium supplementation aimed at symptom control.
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