Forgotten cause of severe hyponatremia

Introduction Sheehan syndrome is (pan)hypopituitarism because of postpartum pituitary infarction due to massive obstetrical hemorrhage. Enlargement of the pituitary gland, smaller sellar region, disseminated intravascular coagulation or autoimmunity are predisposing factors. The absence of lactation after labor and the inability to resume the menstrual cycle later are presenting symptoms. Some patients with Sheehan's syndrome have a sudden onset of severe hypopituitarism immediately after labor, most often in the form of severe hyponatremia. Central adrenal insufficiency is the most usual cause of hyponatremia, although in some cases the syndrome of inappropriate antidiuretic hormone secretion has been also described. Case report A 39-year-old female patient was admitted to the Intensive Care Unit due to severe hyponatremia with neurological symptoms (Na 103 mmol/L, Cl 72 mmol/L, K 3.7 mmol/L), and absence of lactation. Previously, on the sixth postpartum day, she was admitted to the Obstetrics and Gynecology Clinic due to severe headache, nausea, vomiting, and blurred vision. The symptoms persisted since labor, which was complicated with severe hemorrhage (1000 ml) due to obstetric complications. Treatment began with the 3% hypertonic saline solution with restriction of fluid intake. In regard to panhypopituitarism, replacement therapy with hydrocortisone and levothyroxine was initiated. Diabetes insipidus was excluded. Growth hormone replacement therapy and combination of progesterone and progestogens was started during follow-up. Conclusion Early diagnosis of Sheehan's syndrome is essential. Pituitary insufficiency in these patients has a in that can sometimes result in coma and death.