Correlation Study Of EV71 - Induced Immune Injury Of Hand - Foot - Mouth Disease Complicated With Neurogenic Pulmonary Edema

Objective:To investigate the immune mechanism of neurogenic pulmonary edema complicated by enterovirus-71-related hand, foot and mouth disease(HFMD) by detecting the serum levels of cytokines, immunoglobulins, complements and changes of subgroups of T lymphocyte.Methods:According to the clinical symptoms and classification standards, children with HFMD caused by enterovirus-71 were divided into three groups, the critical group(18 cases with neurogenic pulmonary edema and cardiopulmonary failure),the severe group(64 cases with pure encephalitis without pulmonary edema) and the common group(52 cases without complications). Serum levels of immunoglobulins(Ig G, Ig A, and Ig M) and complements(C3 and C4) were detected by immunonehelomitery. And IL-6, IL-10, TNF-α and IFN-γ levels were detected by ELISA. Flow cytometry was used to analyze the percentage of CD3+、CD4+ and CD8+ T cell in leukomonocyte suspensions. Results were analyzed to determine the influence of immune response to children’s condition.Results:① Serum levels of Ig A and Ig G of the critical group and the severe group were drastically lower than the common group with statistical significance(p<0.05). However the difference between the critical group and the severe group were not statistically significant. Levels of Ig M among the three groups were not statistically different(p>0.05). ② Serum levels of C3 and C4 of the critical group were significantly lower than the severe group and the common group(p<0.05). However the difference between the severe group and the common group was not statistically significant. ③ IL-6 levels of the critical group and the severe group were significantly higher than the common group(p<0.05),while the difference between the critical group and the severe group was not statistically significant. ④ IL-10 level of the critical group was higher than the severe group, and the severe group was higher than the common group. All the differences among the three groups were statistically significant(p<0.05). ⑤ The change trend of IFN-γ was similar to that of IL-10, with statistical significance among the three groups(p<0.05). ⑥ TNF-α level of the critical group was lower than the severe group and the common group(p<0.05). However the difference between the severe group and the common group was not statistically significant. ⑦ The percentages of CD3+ and CD4+ T cells of the critical group were obviously lower than the severe group and the common group with statistical significance(p<0.05). ⑧ The percentage of CD8+ T cells of the critical group was slightly lower than the severe group with no statistical significance(p>0.05). However both the critical group and the severe group were statistically higher than the common group(p<0.05). ⑨ The ratio of CD4+ to CD8+ T cells of the critical group was nearly reversed, significantly decreased than the severe group and the commongroup(p<0.05), while the difference between the severe group and the common group was not statistically significant(p>0.05).Conclusion:①Serum levels of IL-10、TNF-α and IFN-γ and the ratio of CD4+ to CD8+ T cells in children with HFMD caused by EV71 in complication with neurogenic pulmonary edema are closely associated with the severity and progression of disease.② Decrease of serum levels of Ig A, Ig G, complement C3 and C4 is, to some extent, related to the severity of disease.③Our research provides experimental basis for clinical diagnosis and treatment of HFMD caused by EV71 in complication with neurogenic pulmonary edema.