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.