A rare autosomal recessive disorder typically presenting in late childhood or adulthood with hypokalemia, metabolic alkalosis, hypomagnesemia, hypocalciuria, and normal blood pressure. Most patients develop symptoms including severe muscle cramping of the arms and legs due to hypokalemia and hypomagnesemia, fatigue due to renal salt wasting and hypotension, polyuria and nocturia due to chronic salt wasting, and chronic hypokalemia, which is a cause of nephrogenic diabetes insipidus and chondrocalcinosis.

The genetic mutation is in the gene coding for the thiazide-sensitive Na-Cl cotransporter in the distal tubule, resulting in a presentation similar to that of patients with chronic thiazide diuretic use. Prevalence is 1 in 40 000.

Related topic: Bartter syndrome