Bartter's syndrome (BS) is a disease with severe hypokalaemia due to renal 
potassium wasting. The potassium loss is due to lesions at different sites 
within the renale tubule. Additional features include metabolic alkalosis, 
excess renal production of prostaglandins, hyperreninaemia, hyperaldosteronism 
and impaired pressor responses to exogenous angiotensin II. These secondary 
features are the result of renal potassium wasting. Symptoms are due to 
potassium deficiency, but many adult patients feel well despite marked 
hypokalaemia. The hypocalciuric variant of BS is called Gitelman's syndrome. 
These patients have a more benign course. The diagnosis of BS is one of 
exclusion, mainly of surreptitious vomiting, diuretic or laxative abuse. The 
primary treatment is potassium supplementation often in combination with 
potassium-sparing diuretics, prostaglandin inhibitors or ACE-inhibitors. With 
coexisting magnesium deficiency, magnesium supplementation might be effective.