Familial hypokalaemia and hypomagnesaemia. A further family.

A family of four siblings is reported. While both parents and one sib appear entirely normal, three other sibs give biochemical evidence of impaired potassium conservation, hypomagnesaemia and decreased urinary calcium output. Affected sibs may be symptom free and of either sex. The dominant clinical abnormality, when it does occur, is tetany and may be precipitated by non-specific illness. Sustained management of the hypokalaemia seems desirable.