An 82-year-old woman with a history of breast cancer was treated with surgery and hormone therapy 20 years ago with hypertensive cardiomyopathy in sinus rhythm, hypercholesterolemia and moderate chronic hyponatraemia around 133 mmol/L. She was treated with hydrochlorothiazide 12.5 mg/24 mg/24 mg hydrochlorothiazide torasem
He started treatment with sertraline 50 mg/24h, with his usual levels of natraemia, due to suspicion of depressive syndrome, six weeks before admission.
After two weeks, her general condition worsened, with nausea, vomiting, need for help for daily activities and behavioral changes.
One month later, hyponatremia of 119 mmol/L was detected, sertraline was discontinued and fluid restriction was initiated at home for three days without remission of symptoms.
She was admitted to Internal Medicine with a diagnosis of confusional syndrome secondary to urinary infection and/or hyponatremia.
Hyponatremia was diagnosed, probably secondary to sertraline.
Blood tests at admission were compatible with SIADH.
Thyroid hormone levels (TSH: 4.04 mIU/L, free T4: 1.72 ng/dL, free T3: 3.13 pg/mL) and cortisol (19.7 μg/dL range) were within normal range.
Hyponatremia was treated on the first day with suspension of sertraline, hydrochlorothiazide and voiding agent initial, furosemide 20/12, fluid resuscitation (1500 mL NaCl/24h i.v.).
The rest of the home treatment was maintained during hospitalization.
Treatment was continued for 4 days with fluid restriction to less than 500 mL daily, improving serum sodium to 132 mmol/L, but two days later decreased again, which led to the use of tolvaptan 24 mg daily.
Natraemia was found to be acceptable in post-hospital discharge controls.
The treatment at discharge was losartan 100 mg/24h, atenol 50 mg/12h, trazodone 50 mg/24h, pravastatin 10 mg/24h, alendronic acid 70 mg/2450 low acid calcium/7 days.
