ABSTRACT

Objectives:

Hyponatremia is an important and common electrolyte disorder. The underlying cause is classified according to serum sodium level, presence of symptoms, serum osmolarity, and volume status, and treatment is planned accordingly.

Materials and Methods:

The demographics, laboratory data, etiologies, treatment choices and outcomes of 25 hypotonic hyponatremia patients who are etiher admitted to Nephrology or consulted between January 2020 and June 2022 in Ankara University İbni Sina Hospital are analyzed.

Results:

Severity of hyponatremia are classified according to serum sodium levels. A serum sodium level of 120 to 129 mmol/L (10 patients, 40.0%) is considered as moderate, where <120 mmol/L (15 patients, 60.0%) is classified as severe hyponatremia. Patients who had severe hyponatremia were more likely to have symptoms compared with patinets who had moderate hyponatremia. (80.0% vs. 30.0% p=0.034). Two thirds of patients had an etiology of syndrome of inappropriate ADH. Fluid restriction is applied in all patients, while isotonic fluid (4.0%), hypertonic fluid (52.0%), tolvaptan (36.0%) and empagliflozin (4.0%) is additionally used in selected patients. Tolvaptan was initiated with a dose of 7.5 mg once daily, and the dose was titrated as needed. Serum sodium levels has been properly raised, and there were no significant differences between groups at the time of discharges. Hyponatremia has recurred in 9 patients (36.0%). In one patient, serum sodium levels has remained steady with empagliflozin therapy in 3 month follow-up. All of the four patients died in follow-up has severe hyponatremia, while this is not statistically significant (p=0.075), is accepted significant clinically.

Conclusion:

Considering the comorbidities and etiology, hyponatremia is an important electrolyte imbalance that causes increased morbidity and mortality. Guiding the treatment with proper diagnostic approach, and choosing tolvaptan and empagliflozin in suitable patient groups holds and important place in correcting hyponatremia appropriately for befitting goals.

Keywords: Hyponatremia, Tolvaptan, SGLT2 Inhibitors

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Approach to Hyponatremia and Treatment Options: A Single Center Experience

ABSTRACT

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