ABSTRACT
Purpose: Severe Fever with Thrombocytopenia Syndrome (SFTS) is an infectious disease with rapid onset and high case fatality rate. The study was to explore the clinical value by examining the serum level of 25-hydroxyvitamin D (25 (OH) D) in SFTS patients. Methods: One hundred and five patients and 156 healthy controls were included. Univariate and multivariate regression analyses were performed to identify independent risk factors for disease progression. Subject operating characteristics (ROC) curves were drawn, and the corresponding area under the curve (AUC) was calculated to assess the sensitivity and specificity of the diagnostic disease. Results: The 25 (OH) D level of disease group was lower than that of healthy control group (22.12 (18.43, 25.86) ng/mL vs 27.36 (23.20, 32.71) ng/mL; P<0.05). The 25 (OH) D level of severe disease group was lower than that of mild disease group (20.55(16.30, 24.44) ng/mL vs 24.94(20.89, 31.91) ng/mL; P<0.05). And there was no significant difference of 25 (OH) D level between the survival group and death group in severe disease group. Multivariate Logistic regression analysis showed that the 25 (OH) D level under 19.665 ng/mL was an independent risk factor for the development of SFTS (OR = 0.901, P=0.040). Furthermore, age more than 68.5 years old and lactate dehydrogenase (LDH) more than 1023.5U/L were independent risk factors for death in severe patients with SFTS. Conclusion: Patients with SFTS have reduced 25 (OH) D level, and 25 (OH) D is a risk factor for disease severity in patients with SFTS. Vitamin D supplementation may be an effective measure to reduce the risk of infection and improve the prognosis.