Bartter syndromes are defined as a family of inherited recessive autosomal 
tubulopathies. They are characterized by hypochloremia, hypokalemia, metabolic 
alkalosis associated with potassium renal leakage and normal blood pressure 
despite increased plasma renin activity. Three forms of the disease are 
identified as followed: 1) Gitelman syndrome or hypocalciuria hypomagnesemia 
syndrome is a mild form often discovered in childhood or teenagers in reason of 
tetany. It is an homogeneous disorder related to mutations of the genes encoding 
the thiazide-sensitive Na-Cl cotransporter located in the distal convoluted 
tubule. 2) Antenatal Bartter syndrome with hypercalciuria and nephrocalcinosis 
or hyperprostaglandin E syndrome is a severe form, often revealed by hydramnios, 
prematurity and growth delay. It is related to mutations of two types of genes 
encoding for transporters of Henle's loop: the bumetanide-sensitive 
cotransporter Na-K-2Cl (NKCC2) [type I] or the inwardly-rectifying potassium 
channel (ROMK) [type II]. 3) the classical form or type III Bartter syndrome, 
often revealed by dehydration in the first year of life, is associated with 
hypomagnesemia in 20% of cases and normal or increased calciuria. This form is 
related to mutations of CLCNKB gene encoding for a chloride channel in Henle's 
loop. This classification, in part related to the demonstration of mutations in 
the genes encoding for tubular chloride or potassium channels, does not fit all 
cases, overlapping syndromes are frequent. Moreover some endocrinological 
(diabetes) and neurological (deafness) abnormalities are sometimes associated 
with Bartter syndromes. Both phenotypic and genetic approach must help to the 
diagnosis of these tubulopathies.