[A case of cerebral polyuric hyponatremia (author's transl)]

A case of cerebral polyuric hyponatremia was reported. A 64-year-old lady had complained of visual disturbance for 4 years. She was operated upon under the diagnosis of tuberculum sellae meningioma. Sever days following operation tremendous polyuria was senn, i. e. polyuria over 40 l/day, massive sodium wasting in the urine, hyponatremia and severe thirst feeling. These situations could not easily controlled by pitressin, and 2 days after the onset of polyuria the level of sodium in the serum decreased up to 112 mEq/l, the amount of excretion of sodium into urine increased up to 186 mEq/l, and the patient had finally a convulsive seizure followed by loss of consciousness. This hyponatremia was easily controlled by infusion of hypertonic NaCl. The pathogenesis of this condition could not be explained by applying the classical concept of "Diabetes Insipidus" nor "SIADH". This hyponatremia might be the result of massive sodium wasting in the urine. And from the results obtained in our patient, these conditions should be classified in the syndrome of "Cerebral Polyuric Hyponatremia" as reported by Oi et al. It should be emphasized that the measurement of osmorality and level of electrolytes in the serum and urine had to be performed frequently when the postoperative polyuric situation was found, so that the clinical diagnosis could be established in the earlier stage. The clinical diagnosis and differentiation of postoperative disorders in water and electrolytes of central origin were discussed.