Objective: The aim of the study was to evaluate the usefulness of copeptin for differentiation of hyponatremia in the course of tick-borne encephalitis (TBE) and for being a prognostic marker of the severity of TBE.
Materials and methods: One hundred and fourteen patients with TBE were included in the study. The control group consisted of 62 patients diagnosed with viral meningitis.
Results: Copeptin concentration did not differ in patients with hyponatremia and normonatremia. Urinary sodium excretion to plasma copeptin (copeptin/UNa Secretion) ratio was significantly lower in Syndrome of Inappropriate Antidiuretic Hormone (SIADH) Secretion patients than in patients with hyponatremia of other origin. Mean copeptin concentration in TBE patients was higher than in control group (VM) patients. There were no differences between patients with severe and mild course of TBE.
Conclusions: Copeptin/UNa ratio may be used as a potential biomarker of SIADH in patients with TBE. Copeptin concentration is significantly higher in patients with TBE than in viral meningitis of other origin, especially in patients aged 18-34 and >49 years old. Copeptin does not differentiate TBE of mild and severe course.
Keywords: Copeptin; SIADH; TBE; copeptin to UNa ratio; hyponatremia; meningitis; tick-borne encephalitis.