Levels And Clinical Significance Of IL-6,IL-10,TNF-α In BALF From Children With Mycoplasma Pneumoniae Pneumonia

Background: Mycoplasma pneumoniae pneumonia is caused by mycoplasma pneumonia infection,it could spread through spatter. Mycoplasma pneumoniae is the smallest pronucleus organism without cell wall between virus and bacterium which can survive independently. At present, Mycoplasma pneumoniae has become one of the significant pathogen of respiratory disease in children, and it can cause sporadic respiratory infection and prevalence. Mycoplasma pneumoniae pneumonia is atypical primarily pneumonia caused by mycoplasma pneumoniae, its clinical manifestation is generally characterized by irritable cough and it shows long-term fever at the same time. Physical sign in bellows is unobvious, but the change of imageology is notable. That physical sign is discordant with symptom and imaging is mycoplasma pneumonia's character. The incidence rate of MPP is increasing evidently in recent years,it accounts for 20%-30% of all kind of respiratory infection in children, MPP has been the more common pneumonia in school child and teenagers, and also considerable in infant period.The age of onset has the trend of becoming yonger in recent years.MP can not only cause below affections,but also induce damage to many organs besides respiratory system by immunologic mechanism, such as nervous system, digestive system, hematological system, urinary system, cardiovascular system and so on. Extrapulmonary complications occur in the end. Some patients have long duration and severe illness, it even lead to multiple organ dysfunction syndrome or multiple organ failure.Currently more clinical data indicate that mycoplasma pneumoniae infection has close relationship with child recurrent respiratory tract infection, SLE, infectious monocytosis, repeated wheezing and even asthma. So the pathogenesis of MPP has caused great attention of the scholar out and in. Until now the mechanism of MPP has not been clarified, immune response and MP adhension to airway epithelial cell may be involved in the mechanism. MP infection is a kind of immune response of organism toward microorganism, MP can activate the immune system respond to foreign antigen, and during the course cytokines play a important role in the interaction between immune cells.Some studies suggest that cytokines parcipate in immune response, inflammatory reaction and immune injury, and so it plays a vital role in the occurrence and development of MPP.Many researches from home and abroad indicate that MP can induce the generate of many kinds of cytokines,such as IL-2,IL-4,IL-6,IL-10,IFN-γ,TNF-αand so on. IL-6 is pleiotropy cell factor secreted by lymphocyte and mononuclear macrophage. It is a medium in the acute phase of infection and injury, and it also modulate immune, stress and inflammatory responses, so it makes a difference in the respects of anti-infection, autoimmune and so forth. IL-10 is a kind of protein secreted by Th2 cell, which could inhibit Th1cell. Its main biological function is to restrain the inflammation. It protects our body from the damange of excessive inflammatory. TNF-αis a polypeptide regulatory factor secreted by mononuclear macrophages, which has many biologic activities. It is a important mediator in the couse of the onset of immune defence, inflammatory injury and shock. The biologic activity of TNF-αis changing with its concentration in organism. If the concentration is too high, it can not help to anti-infection, on the contrary,it results in many pathological process of inflammatory response, and lead to severe local inflammatory reaction and even organ disfunction. So far there are a great quantity of reports about the blood and sputum focused on the cytokine level but rarely about the bronchoalveolar lavage fluid (BALF). BALF comes from the illed bronchopulmonary tissue, so it may reflect the pathological changes of the respiratory system more directly and accurately than either blood or sputum. So we carry out the detection of the cytokines IL-6,IL-10,TNF-αin children with MPP.Objectives: To study the pathogenesis of Mycoplasma pneumoniae pneumonia and the relationship with the immune system ,on the other hand to explain the effect of IL-6,IL-10,TNF-αin the pathogenesis of MPP.Methods: BALF are collected undergone bronchofibroscopy in all subjects investigated, and at the same time vein blood is taken suction and centrifugated, the serum was remained. BALF and serum IL-6,IL-10,TNF-αare measured in 30 cases of children with the acute phase of MPP, 15 cases with MPP in the recovery phase and 8 cases of the control group without pulmonary pathological changes by doubleantibody sandwich enzymelinked immune- osorbent assay (ELISA) respectively. All data is statistically analyzed by the application SPSS13.0Results:1.The changes of BALF and serum IL-6 in three groups: Comparisons of biological parameters between the three groups of cases were made using analysis of variance.There was statistically significant difference among the three groups (P<0.05). We further compared between every two groups of them. The results showed that the level of BALF and serum IL-6 in patients with MPP of the acute phase were higher than those in the recovery phase of MPP and the control group, there was statistically significant difference for IL-6 level among them (P<0.05). There was no statistically significant difference between the convalescence phase of MPP and the control group (P>0.05).2. The changes of BALF and serum IL-10 in three groups:Comparisons of biological parameters between the three groups of cases were made using analysis of variance.There was statistically significant difference among the three groups(P<0.05). We further compared between every two groups of them.Compared with the control group,the level of BALF and serum IL-10 in cases with the acute and convalescence stage of MPP were higher, there was statistically significant difference among them(P<0.05). There was no statistically significant difference between the acute and the convalescence phase of MPP(P>0.05).3. The changes of BALF and serum TNF-αin three groups: Comparisons of biological parameters between the three groups of cases were made using analysis of variance.There was statistically significant difference among the three groups (P<0.05). We further compared between every two groups of them.The results showed that the level of BALF and serum TNF-αin cases with MPP of the acute stage were higher than those in the convalescence stage of MPP and the control group, there was statistically significant difference for TNF-αlevel among them (P<0.05). There was no statistically significant difference between the convalescence stage of MPP and control group (P>0.05).Conclusion:1. The levels of BALF and serum IL-6,IL-10,TNF-αin the acute phase of MPP were higher than those in the control group,and in the convalescence stage of MPP, the level of IL-10 was sustained high, while the level of IL-6,TNF-αhad dropped to the normal range.It suggests that IL-6,IL-10,TNF-αare involved in the pathogenesis of MPP.2. The BALF was in accordance with serum in two kinds of specimens examination result of the levels of IL-6,IL-10,TNF-α.The cytokine concentration in BALF was higher than that of serum, both positive related.