Serum Levels of Mannan-Binding Lectin in Patients with Crimean-Congo Hemorrhagic Fever

Abstract

Mannan-binding lectin (MBL) is a central component of the innate immune response. Genetic variations in the MBL gene that reduce circulating levels and alter functional properties of the MBL are associated with susceptibility for many infectious diseases. Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne disease caused by an arbovirus in the family Bunyaviridae. We have investigated serum MBL levels in CCHF patients and a possible association between circulating MBL concentrations and the severity of CCHF. Forty-seven patients found to have CCHF in Cumhuriyet University Hospital and 29 healthy controls were recruited for this study. There were no differences in terms of age and sex between the patients and the healthy controls (p = 0.64 and p = 0.484, respectively). This study was conducted between July 1 and August 31, 2007, in Cumhuriyet University Hospital in Sivas, a city located in the central Anatolian region of Turkey. Patients with CCHF were matched with healthy controls, and serum MBL levels were measured. The median serum MBL level was significantly lower in the patient group than in the healthy control group (48.0 ng/mL [inter-quartile range (QR) 30.4-128.0] and 212.0 ng/mL [IQR: 115.8-524.0], respectively; p < 0.001). No significant difference was found between serum MBL levels in CCHF patients with severe and nonsevere form of the disease (p = 0.167). MBL levels were significantly lower in patients with CCHF than in healthy controls. There was no meaningful correlation between the serum MBL level and severity of CCHF disease. Low serum MBL level may be associated with the high consumption of MBL in CCHF infection and/or MBL gene polymorphism.