Evaluation of endothelium functions by flow-mediated dilatation in pediatric patients with Crimean-Congo hemorrhagic fever.

Background: Crimean-Congo hemorrhagic fever (CCHF) is a systemic viral disease that also affects the endothelium. Thrombocytopenia and hemorrhage are seen in this disease. But, the cause of thrombocytopenia is not clear. We hypothesized that endothelium dysfunction may be the cause of thrombocytopenia. We evaluated the endothelium functions by flow-mediated dilatation (FMD) in CCHF.
Methods: Consecutive children with suspected CCHF who applied to our hospital were evaluated for recruitment into the study. FMD analysis was done in the active and healing period of the disease. Diagnosis was confirmed or ruled out by polymerase chain reaction and/or ELISA test. Basal brachial artery diameter (BBAD) and dilated brachial artery diameter (DBAD) after ischemic period were measured and percent dilatations [(DBAD-BBAD)/BBAD, FMD%] were computed from all subjects.
Results: Fifty-four children (40 male, mean age 12.4 ± 4.4 years) were recruited into the study. CCHF diagnosis was confirmed in 28 children and ruled out in 26 children. Groups were similar for age and gender. FMD% was significantly decreased in CCHF patients when comparing this with the control patients in the active period (2.65 ± 2.76 vs. 13.76 ± 7.95, P < 0.001). FMD% was correlated with platelet count in the active period of the disease (r = 0.599, P = 0.004). FMD% was recovered in the healing period (2.65 ± 2.76 vs. 14.72 ± 2.66, P < 0.001) and was not significantly different from basal values of control patients (P > 0.05).
Conclusions: FMD is significantly decreased in CCHF and recovers in the healing period. So, endothelium functions are disturbed, and disturbance is correlated with thrombocytopenia in CCHF.