Background: Inappropriate antidiuretic hormone secretion syndrome is rare in patients with gynecologic tumors.
Case: A 22-year-old woman presented with inappropriate antidiuretic hormone secretion symptoms during the 2 months preceding the diagnosis of an immature ovarian teratoma. Vasopressin levels in serum and in the urine were very low. Restriction of water intake and surgical removal of the teratoma resulted in the definitive correction of the hyponatremia. This observation suggests that immature teratoma cells can produce a vasopressin-like factor, and the syndrome may be a sign of an ovarian malignancy.
Conclusion: Pelvic organs should be examined when the more common causes of inappropriate antidiuretic hormone secretion syndrome have been ruled out.