Study of the changes of immune status in children with HFMD caused by EV71 virus

Objective To study the changes of immune status in children with HFMD caused by EV71 virus. Methods HFMD patients were divided into three groups, called the common type, the severe type and critical type,respectively,according to the clinical diagnosis and classification standards, meanwhile, healthy children were taken as a control group. Peripheral blood samples were collected from the case groups and control group, and the concentions of interleukin-13(IL-13) and interferon-γ(IFN-γ) were tested by the chemiluminescence assay, immunoglobulin(IgG, IgA, and IgM) were also tested by the immunoturbidimetric assay, as well as, the relative contents of T cell subsets, B cells and NK cells were tested by Flow cytometry. Results Compared the detected results of three types of HFMD with those of the control group, the levels of IgG, IgA, IgM, IL-13 and IFN-γ were significantly increased, all the differences were statistically significant(P0.01), except the difference of IgG, and IgA between the ordinary type and the control group. Moreover, compared with the three types of HFMD, the concentrations of five indicators were also increased as the disease becoming worsen, all the differences were statistically significant(P0.01). Compared the common type group with the control group, the percentage of CD3+, CD4+, CD8+were slightly increased, but the differences were not statistically significant(P0.05). Meanwhile, the percentage of CD16+56+and CD19+were dramatically increased, the differences were statistically significant(P0.01). Compared the other two types with the control group, the percentage of CD3+, CD4+, CD8+and CD16+56+were significantly decreased, but CD19+was significantly increased, and all the differences were statistically significant(P0.01). However, the ratio of CD4+/CD8+did not change drastically, and there were no differences among all the groups(P0.05). Compared the three types of HFMD with each other, the percentage of CD3+, CD4+, CD8+and CD16+56+were decreased continuously as the disease becoming worsen, while the CD19+were increased constantly, all the differences were statistically significant(P0.01). Conclusion The children with HFMD caused by EV71 infection exist functional disorders of cell immunity, humoral immunity and innate immune, and related with severity of the disease.