Endothelial Dysfunction in Asthmatic Children and its Correlation to Clinical and Functional Severity

Abstract

Summary and Conclusion A sthma is a disease characterized by airway chronic inflammation and bronchial hyperactivity, involving the imbalance of oxidative and antioxidative agents. There is an increased free radical generation and a decreased antioxidant enzyme activity, which correlate with the severity of the disease. Endothelial dysfunction is a systemic pathological state of the endothelium and can be broadly defined as an imbalance between vasodilating and vasoconstricting substances produced by (or acting on) the endothelium. This current study aimed at assessment of endothelial function parameters namely flow mediated dilatation (FMD), flow mediated resistive index,(FMRI), and circulating endothelial cells count (CEC) in asthmatic children of various functional and clinical severity and correlating the studied endothelial function parameters with the level of disease control and severity. This study included 40 asthmatic children (28 males and 12 females) attending the Pediatric Chest Clinic, Children's Hospital, Ain Shams University. According to clinical severity those patients were divided functionally into mild persistent asthma (11 patients, 8males, 3 females), moderate persistent (15 patients, 11 males, 4 females), and severe persistent asthma (14 patients, 9 males, 5 females). According to level of control, they were classified into controlled (19 patients, 13 males, 6 females), partially controlled (10 patients, 6 males, 4 females) & uncontrolled (11 patients, 9 males, 2 females). According to exposure to smoking, they were classified into positive second hand smoke (25patients, 18 males, 7 females), and negative second hand smoke (15 patients, 10 males, 5 females). 12 Age and sex matched apparently healthy children were been selected as a control group. For all studied case and control group through history, clinical examination, CBC, and IgE, were done and spirometric pulmonary function (FEV1, FVC) % of predicted were measured in pulmonary function lab, pediatric hospital, Ain shams university, and then we asses endothelium function through ultrasonographic evaluation of brachial artery measuring flow mediated dilatation (FMD ),and flow mediated resistive index (FMRI) ,also we asses laboratory circulating endothelial cell (CEC) and correlate endothelium function with asthma severity and level of control. Studied groups were well matched as regards age, gender, and residence distribution (p>0.05 for all) respectively. Studied asthmatics had significantly higher mean values of absolute esinophilic count and IgE level compared to controls (P < 0.01 for both). There were statistically insignificant differences between both studied groups as regards the mean values of the performed pulmonary function tests (p > 0.05). Studied asthmatics had significantly higher mean values of circulating endothelial cell count compared to controls (P< 0.05).