Study On Immune Function In Children With Severe Hand-foot-mouth Disease

Objective: Many studies have been conducted at home and abroad on the pathogenesis of hand-foot-mouth disease(HFMD)and serum levels of cytokines in peripheral blood of HFMD patients in recent years,but early identification of severe cases is difficult due to the special pathogenesis of HFMD.Since some cytokine abnormalities are related to the occurrence of severe cases,the occurrence of severe complications is often caused by abnormal cytokine activation after virus infection,resulting in clinical manifestations such as brain stem injury,severe systemic inflammatory reactions,and increased pulmonary vascular permeability.Tests of related cytokines may contribute to the early detection of severe cases of HFMD.This study was designed to detect the levels of cytokines,including IL-1?,IL-2,IFN-?,IL-4,IL-6,and IL-10,in peripheral blood of pediatric patients with severe HFMD and to understand the dynamic changes of Th1/Th2 in vivo,to explore the immunological changes induced by the changes of proportion of helper T cell(Th)subsets in HFMD children,and to further elucidate the dynamic changes of immune function in children with HFMD,contributing to the early diagnosis of severe cases and providing reference for clinical diagnosis and treatment of the disease.Methods:1 Selections of the case group and the healthy control groupFor the case group,a total of 22 children with severe HFMD were selected from patients hospitalized in the Pediatrics Department of Cangzhou Central Hospital from Dec.2013 to Dec.2015,in which 13 patients were males and 9 females,with a mean age of(2.3±0.8)years(ranged from 0.8 to 4.0 years).The diagnostic criteria of severe HFMD were referred to the Diagnostic criteria of severe hand foot mouth disease from the Guidelines for the Diagnosis and Treatment of HFMD(2012 Edition),combined with clinical diagnosis.For the control group,33 children(male 18,female 15)who were physically examined in Cangzhou Maternal and Child Health Hospital were selected from a daycare center,with a mean age of(2.7±0.9)years(ranged from 2.3 to 4.0).Routine laboratory tests were normal and viral infections were excluded for all these children.There was no significant differences in age and sex between the two groups(P>0.05).2 Case follow upClinical data and relevant data for clinical treatment of the children were collected.3 Specimen collection: Fasting whole blood of 2ml was collected from each subject and placed in vacuum sterile EDTA anticoagulant tubes.Blood specimens were stored and processed according to the instruction from "Guidelines for prevention and control of hand foot mouth disease”(2012 Edition).4 Measurement of cytokinesIFN-? and IL-4 levels in peripheral blood were measured by flow cytometry to indirectly determine the numbers of Th1 and Th2 cells,and immune function of the patients was subsequently evaluated by the changes of Th1/Th2(IFN-?/IL-4).In order to explore the relationship between the abnormal expressions of cytokines and the occurrence of severe HFMD,levels of cytokines IL-1?,IL-2,IL-6,and IL-10 in peripheral blood were measured by Antibody-Sandwich ELISA,and were compared with that of the age-matched healthy children.5 The measured results of cytokines were expressed as `x±s.SPSS 15 software was used for statistical analysis,and ?=0.05 was set as the test level.Measurement data was analyzed using independent sample t test.P<0.01 was considered as significant difference.Results:1 Quantitative comparison of cytokines in peripheral blood of children with severe HFMD(before treatment)The peripheral blood levels of IL-1?,IL-2,IL-6,IL-10,and IFN-? in the case group(prior to treatment)were increased in various degrees when compared with the control group,and the differences were statistically significant(P<0.01).While IL-4 was increased slightly than the control group,with no statistically significant difference(P>0.05);2 Quantitative comparison of cytokines in peripheral blood of children with severe HFMD(recovery treatment)The level of IL-10 in the experiment group(recovery period)was increased compared with that of the control group(P<0.01),with a statistically significant difference;There were no statistically significant differences of the IFN-?,IL-1?,IL-2,IL-4,and IL-6 levels between the two groups(P>0.05);3 Comparative analysis of Th1/Th2 in children with severe HFMDBefore treatment,the Th1/Th2 of the experiment group was significantly increased versus the control group(P<0.01);at recovery period,the Th1/Th2 of the experiment group was not significantly different from that of the control group(P>0.05);the Th1/Th2 before treatment was also significantly higher than that of the recovery period(P<0.01).Conclusion:1 Differentiation balance disorder Th cells exists in children with severe HFMD,with Th0 inclined to polarize to Th1.Abnormally expressed cytokines lead to an intense inflammatory and anti-inflammatory response state of the body.2 In the recovery period,the proportion of Th1/Th2 decreases in children with HFMD,and the imbalance is improved.3 In the recovery period,the IL-10 level of peripheral blood in children with HFMD is slightly higher than that in the control group,which was beneficial to immune recovery.