Clinical study on desmopressin acetate therapy in patients with adipsic hypernatremia: Five cases report

Abstract

Objective Adipsic hypernatremia is very rare in clinical practice and only a few cases have been reported so far. Since the pathogenesis of adipsic hypernatremia is unclear, therapeutic method is very limited and uncertain. We previously found the existence of partial central diabetes insipidus in the patient with adipsic hypernatremia according to a series of clinical studies. In this clinical study, we observed the response of vasopressin in the treatment of adipsic hypernatremia as a routinely used agent in treating central diabetes insipidus.Methods Five patients with chronic sustained hypernatremia and hypodipsia were diagnosed as adipsic hypernatremia according to the criteria by Halter. After testing plasma electrolytes, urinary osmolality, plasma osmolality, and free water clearance (CH2O);with evaluating thirsty grade and anterior pituitary function, patients were forced to drink water 2 000-2 500 ml each day combined with prednisone and/or levethyroxin supplementation therapy if hypopituitarsm was revealed. One week later, since the hypernatremia was unrelieved, desmopressin acetate (0.05-0.2 mg/d)was administered to those 5 patients. About 5-7 days later, plasma electrolytes, urinary and plasma osmolality, and free water clearance ( CH2O ) were reevaluated. Osmolality was detected by the method of freezing point depression and thirst grade by the method of visual analogue scales. Results The plasma sodium was 160-190 mmol/L and plasma osmolality was 330-370 mmoL/L without thirsty perception during the hospitalization. Four of the five patients were revealed to be suffering from hypopituitarism, but the hypernatremia could not be corrected by intentional water intake combined with prednisone treatment. After administering vasopressin 0.05-0.2 mg/d to these patients, that hypernatremia was relieved, and hyperosmolality and hypodypsia were improved effectively. During this period of time, no side effects were detected in these patients. Conclusion We testified the existence of central partial diabetes insipidus in the patients with adipsic hypernatremia. Desmopressin acetate in the treatment of adipsic hypernatremia is proved to be effective, simple, and safe. Key words: Adipsic hypernatremia; Central diabetes insipidus; Therapy; Vasopressin