Early-Onset Gitelman Syndrome With Normomagnesemia and Absence of Metabolic Alkalosis: Expanding the Phenotypic Spectrum

Abstract

Abstract Gitelman syndrome is an autosomal recessive tubulopathy caused by SLC12A3 mutations and typically presents with hypokalemia, metabolic alkalosis, and hypomagnesemia. However, atypical phenotypes are increasingly recognized. We report a four-year-old child with recurrent hypokalemia without hypomagnesemia or metabolic alkalosis. Genetic analysis revealed compound heterozygous SLC12A3 variants, including a missense mutation and a novel frameshift mutation. This case expands the phenotypic and mutational spectrum of Gitelman syndrome and highlights that it should be considered in pediatric hypokalemia even in the absence of classical biochemical features. Keywords Gitelman syndrome; SLC12A3; hypokalemia

Keywords

• Gitelman syndrome
• SLC12A3
• hypokalemia

Normomagnezemi ve Metabolik Alkaloz Yokluğu ile Seyreden Erken Başlangıçlı Gitelman Sendromu: Fenotipik Spektrumun Genişletilmesi

Abstract

Özet Gitelman sendromu, SLC12A3 mutasyonlarının neden olduğu otozomal resesif bir tübülopatidir ve tipik olarak hipokalemi, metabolik alkaloz ve hipomagnezemi ile seyreder. Ancak atipik fenotipler giderek daha sık tanımlanmaktadır. Bu olgu sunumunda, hipomagnezemi veya metabolik alkaloz olmaksızın tekrarlayan hipokalemi ile başvuran dört yaşında bir çocuk sunulmuştur. Genetik analizde, missense bir mutasyon ve yeni bir frameshift mutasyonu içeren bileşik heterozigot SLC12A3 varyantları saptandı. Bu olgu, Gitelman sendromunun fenotipik ve mutasyonel spektrumunu genişletmekte ve klasik biyokimyasal özellikler bulunmasa bile pediatrik hipokalemi olgularında Gitelman sendromunun düşünülmesi gerektiğini vurgulamaktadır. Anahtar Kelimeler: Gitelman sendromu; SLC12A3; hipokalemi

Keywords

• Gitelman Sendromu
• SLC12A3
• Hipokalemi

References

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