Bartter's syndrome in two successive generations of a Saudi family

Bartter's syndrome (BS) is characterized by primary renal tubular hypokalemic metabolic alkalosis, hyperreninemia, hyperaldosteronism and normal blood pressure. The parents and siblings of a BS patient were evaluated for renal tubular function. The father and all 9 siblings of the patient had biochemical features of BS. His mother, a first cousin of his father, had hypokalemia and hyperkaluria but no other features of BS and could have been a 'carrier'. The mother and all 9 siblings were asymptomatic. Including the patient, hypomagnesemia was present in 8 of 12 family members. Therapy with a combination of potassium chloride and magnesium increased the serum potassium and magnesium levels to within normal limits. The familial occurrence in BS is well known, and reports of the disorder in siblings and the first generation of children of consanguineous marriages and normal parents have been taken to suggest an autosomal recessive inheritance. One affected parent and involvement of all siblings of the patient raise the possibility of an autosomal dominant inheritance in the present family.