CHARACTERISTIC INDICATORS OF ENDOTHELIAL FUNCTION AS DIAGNOSTIC AND PROGNOSTIC CRITERIA OF THE COURSE OF HEMORRHAGIC VASCULITIS IN CHILDREN

Background. Noninvasive ultrasound methods allow to measure the sickness of the intima-media complex and reveal stenosis, occlusions or aneurysms as well as find first preclinical signs of endothelial dysfunction in hemorrhagic vasculitis (HV). The aim of the study was to investigate the structural and functional state of the vascular endothelium by evaluating the sickness of the intima-media complex of the common carotid artery (IMC CCA) and indicators of changes in endothelium-dependent dilation of the brachial artery in children with HV of various severity at different stages of the disease. Material and methods. A total of 39 children aged 4 to17 years with various clinical forms of HV were examined. The sickness of the intima-media complex of the common carotid artery was evaluated by ultrasound examination (Pignolli P., 1986), the reactive hyperemia test was performed according to the technique of Celermajer et al. (1992), the indices of quantitative estimation of blood flow parameters were determined by means of the digital ultrasonic diagnostic Doppler unit Ultima PA with a 10.0-15.0 MHz linear transducer. In accordance with the classification of reaction types of endothelium-dependent dilatation of the brachial artery we distinguished a positive reaction (increased brachial artery diameter by up to 10% from the baseline), a negative reaction (absence of changes in the assessed parameters) and a vasospasm. Results. During the symptomatic period of HV vasoconstriction was recorded in 87% of patients while during the recovery period it was found in 56% of patients. The thickness of the IMC CCA in patients with mild and moderate course of HV did not differ from values in children of the control group. Children with severe HV during the acute phase of the disease demonstrated significantly higher results as compared to the children of the control group. The thickness of the IMC CCA during the administered therapy did not reduce as compared to the baseline. Conclusion. The IMC CCA index can be used as a marker of severity and a diagnostic criterion of high activity as well as a predictor of unfavourable course of the pathological process in children with HV.