Reduction of hyponatremia in a schizophrenic with polydipsia-hyponatremia syndrome by surgical intervention.

In a chronic schizophrenic with polydipsia-hyponatremia syndrome, we observed physiological data consecutively before and after a successful LAPIDES vesicostomy for his bladder retention. Although his polydipsia was unchanged, frequency of hyponatremia was significantly reduced after the operation. We found that bladder retention might be one of the factors relevant to the prediction of hyponatremia from diurnal weight gain.