Endocrine Abstracts

Introduction: Hyponatremia is the most common electrolyte disorder that occurs in 15-30% of hospitalized patients. It is manifested by a wide range of clinical changes, from very mild to life-threatening conditions. Hyponatremia in the elderly is mainly caused by drugs (thiazides and antidepressants), SIADH or endocrinopathies. The paper presents a patient with severe hyponatremia after surgery of subdural hematoma and oxcarbazepine therapy.

Case report: A 77-year-old female was admitted to the Department of internal diseases in 2023, September due to slow speech, disorientation, inability of walking, occasionally abdominal pain. At the end of August 2023. she had a surgery of subdural hematoma due to nausea, headache, walking instability with preoperative normal mineral status. Her cousin denies vomiting, diarrhea, head injuries. The patient was taking enalapril hydrochlorothiazide, rosuvastatin in therapy. She was conscious, oriented, bradipsychic, lightly dehydrated, normotensive on admission but later was hypotensive in Intensive care Unit. Also oxcarbasepine therapy mentioned in a Neurosurgery discharge letter due epilepsy but denied taking it. Low values of sodium were noticed at biochemical findings. Other parameters were normal including glucose, renal, hepatic. Urine culture was positive in Escherichia coli. Serum sodium was corrected with small volume of hyperosmolar sodium chloride at admission due acute hyponatremia and later with isotonic sodium chloride. Due epilepsy attack during hospitalization neurologist consulted and oxcarbasepine started. Sodium diminished and the medication discontinued with the consecutively rising of serum sodium. The patient was conscious, oriented, communicative but not able to walk by herself during the hospitalization.

Conclusion: Evaluation of hyponatremia in the elderly is a challenge for the physician. A female patient had anamnesis and symptoms (hypotension, head surgery, improving with isotonic saline) which could favour a cerebral Salt wasting syndrome. On the other side there are uncertain data on using an oxcarbasepine after head surgery as a cause of SIADH which also developed during second hospitalization. These two entities are overlapping with different treatment options.

Keywords: subdural hematoma, hyponatremia, oxcarbasepine, a cerebral Salt wasting syndrome, SIADH