Can Fractional Exhaled Nitric Oxide (FeNO) Serve as a Clinical Indicator for Patients Hospitalized with Crimean-Congo Hemorrhagic Fever?

Abstract

Crimean-Congo Hemorrhagic Fever (CCHF), a zoonotic disease spread by infected viruses, can be a significant cause of morbidity and mortality in endemic areas. This prospective study aimed to establish a connection between exhaled nitric oxide (FeNO) levels and the clinical prognosis of CCHF. The study included a total of 85 participants: 55 patients followed for CCHF between May and August 2022 and 30 healthy controls. The patients' FeNO levels were measured at admission to the hospital. FeNO levels were 7.6 ± 3.3 parts per billion (ppb) in patients with mild/moderate CCHF, 2.5 ± 2.1 ppb in patients with severe CCHF, and 6.7 ± 1.7 ppb in the healthy control group. There was no statistically significant difference in FeNO between the control group and patients with mild/moderate CCHF (p=0.09), whereas patients with severe CCHF had lower FeNO levels than both the control group and patients with mild/moderate CCHF (p < 0.001 for both). FeNO measurement may offer a noninvasive, easily applied approach for predicting the clinical course and prognosis of CCHF in the early stages of the disease.