Endocrine Abstracts

Introduction: Diabetes insipidus (DI) is a rare condition characterized by excretion of large amounts of dilute urine and increased thirst due to deficiency or renal resistance of antidiuretic hormone (ADH). DI is often difficult to diagnose reliably and accurately, especially in patients with partial DI.

Aim: The aim of our case report is to present the patient with partial diabetes insipidus and to report the results of water deprivation and hypertonic saline stimulation tests.

Material and methods: 18-year-old female patient was admitted to the hospital with chief complaints of increased thirst and urinary frequency after transnasal adenomectomy.

Results: In accordance with the results of water deprivation and hypertonic saline stimulation tests partial ADH-deficiency was diagnosed in our patient due to maximum urine osmolality of less than 539 mOsm/kg and 504 mOsm/kg, plasma osmolality 292 mOsm/kg and 311 mOsm/kg, maximum plasma sodium was 144,4 mmol/l and 143 mmol/l, respectively, and no change in urine osmolality after administration of 0.1 mg desmopressin sublingually.

Conclusion: Postoperative diabetes insipidus is often transient, which occurs as our data show in the gradual restoration of ADH secretion through the clinic of partial diabetes insipidus (ADH deficiency).