The Level And The Clinical Significance Of Serum Interleukin-6 In Children With Mycoplasma Pneumoniae Infections

Objective: To study the pathogenesis of Mycoplasma pneumoniae and to explain the effect and the clinical significance of serum Interleukin-6 in children with Mycoplasma pneumoniae infections.Methods: In this study, cases were divided into three groups, i.e. Mp infection group, non-Mp infection group and normal control group. All cases selected based on their clinical symptoms, signs, chest radiographic features, results of Mycoplasma pneumoniae IgM-antibody test and cold agglutinin test. Cases were eliminated, if they have history of immune system disorder or of intakes of something which influence human immune status. Patients were children with lower respiratory tract infections. The control group was made of healthy children confirmed medically in pediatric out-patient clinic. Experimental methods we used were partial agglutination assay for Mp-IgM-antibodies, cold agglutinin test, enzyme-linked immunosorbent assay (ELISA) for human serum interleukin-6 (IL-6). We used the log of serum IL-6 level to normalize the distribution of IL-6 values and to permit the use of the analysis of variance. Results were described in the form of means±standard deviation ( X±s) and analyzed through analysis of variance for the difference between three groups.Results: Comparisons of biological parameters between the three groups of cases were made using analysis of variance. To normalize the distribution of IL-6 values and to permit the use of the analysis of variance, we used the log of serum level. The log values figured out means±standard deviation. Results indicated superficially that the level of IL-6 in non-Mp infection group was higher than that in control group, and the level of IL-6 in Mp infection group was the highest of the three groups. The result of analysis of variance was F=21.776, P < 0.01. There was statistically significant difference between three of them. We further compared between every two groups of them. Results showed that IL-6 levels in cases of Mp infections were higher than those in control group. P<0.01, There was statistically difference for IL-6 level between them. IL-6 levels in cases of non-Mp infections were higher than those in control group. P<0.05, There was statistically significant difference between them. IL-6 levels in cases of Mp infections are higher than IL-6 levels in cases of non-Mp infections. P<0.01, There was statistically significant difference between them.Conclusion:Levels of IL-6 in children with Mp infections were higher than those in healthy children and higher than children with non-Mp infections as well. We came to conclusions as follows:⒈IL-6 involved in the pathogenesis of the acute phase of Mycoplasma pneumoniae infections.⒉It was implicated that immune responses caused by Mp infections were more intensive than those caused by non-Mp infections due to the result of higher IL-6 levels in children with Mp infection than in children with non-Mp infections.⒊Excessive IL-6 play a essential role in the pathogenesis of Mp infection by its proinflammatory function.⒋Serum IL-6 can be used as an indicator in severity of Mp infection.⒌Serum IL-6 level was significantly increased in the acute phase of Mp infection. The IL-6 concentration in patient infected with Mp can provide a basis for the early treatment with immunomodulator.⒍IL-6 was a critical cytokine in the acute phase of Mp infection. Its serum concentration provided clinicians with important information for the outcome of the disease.