Gitelman syndrome due to p.A204T mutation in CLCNKB gene

A 45-year-old woman presented with phenotypical features suggestive of Gitelman syndrome (adult age at diagnosis, normal–low blood pressure, hypokalaemia, metabolic alkalosis, hypomagnesaemia, and hypocalciuria). Mutational analysis revealed no significant abnormality in SLC12A3 gene, but homozygous p.A204T mutation was found in the CLCNKB gene. This is a founder effect mutation described in Spanish patients with classic and atypical Bartter syndrome. This report confirms previous descriptions and expands the clinical spectrum of this mutation.