[Bartter syndrome, severe rare orphan kidney disease: a step towards therapy through pharmacogenetic and...

Bartter syndromes (BS) types 1-5 are rare salt-losing tubulopathies presenting with overlapping clinical phenotypes including marked salt wasting and hypokalemia leading to polyuria, polydipsia, volume contraction, muscle weakness and growth retardation. These diseases are due to an impairment of sodium, potassium, chloride reabsorption caused by mutations in genes encoding for ion channel or transporters expressed in specific nephron tubule segments. Particularly, BS type 3 is a clinically heterogeneous form caused by mutations in CLCNKB gene which encodes the ClC-Kb chloride channel involved in NaCl reabsorption in the renal tubule. Specific therapy for BS is lacking and the only pharmacotherapy up today available is purely symptomatic and characterized by limiting side effects. The improvement of our understanding of the phenotype/genotype correlation and of the precise pathogenic mechanisms associated with BS type 3 as well as the pharmacological characterization of ClC-K chloride channels are fundamental to design therapies tailored upon patients' mutation. This mini review focused on recent studies representing relevant forward steps in the field as well as noteworthy examples of how basic and clinical research can cooperate to gain insight into the pathophysiology of this renal channelopathy, paving the way for a personalized therapy.