Effects Of Different Pathogenic Microorganisms On The Concentration Of IL-6,TNF-αand SIgA In BALF

Objective To investigate the effects of different pathogens on the concentration of interleukin-6(IL-6),secreted IgA(s IgA)and tumor necrosis factor-α(TNF-α)in alveolar lavage fluid(BALF).To evaluate the significance of IL-6,TNF-α and s IgA concentrations in BALF in differentiating the severity of lower respiratory tract infection.Methods(1)According to inclusion and exclusion criteria,all patients diagnosed with pneumonia were divided into low-risk group(≤90 points),medium-risk group(91-130points)and high-risk group(> 130 points)according to pneumonia severity Index(PSI);The included patients were divided into gram-positive bacterial infection group,gram-negative bacterial infection group,atypical bacterial infection group and fungal infection group according to the pathogen type of infection.All included patients were divided into groups according to the detected pathogens,and the top 5 pathogens were counted and compared.The included cases were divided into pneumonia group,severe pneumonia group and chronic obstructive pulmonary disease with infection group by disease.(2)After admission,sputum was left for culture,or electronic bronchoscopy was performed to collect BALF for culture,and metagenomic sequencing(m NGS)was used to detect pathogenic bacteria.Enzyme-linked immunosorbent assay(ELISA)was used to detect the concentration of IL-6,TNF-αand s IgA in BALF.(3)SPSS 21.0 software was used for data analysis,sorting and statistics.Results(1)PSI scores of pneumonia patients were divided into groups,and il-6concentrations of low-risk group,medium-risk group and high-risk group were compared with statistical significance(P < 0.05),and IL-6 gradually increased with the increase of risk.The concentrations of TNF-α among all groups were compared as follows: there were statistically significant differences between the high-risk group and the low-risk group,and the medium-risk group and the low-risk group(P < 0.05),and the risk of high risk and stroke was higher than that of the low-risk group;there was no statistically significant difference between the high risk group and the medium-risk group(P > 0.05).After the comparison of s IgA among all groups,there was no statistical significance in the above three risk groups(P > 0.05).(2)The patients with lower respiratory tract infection were classified and compared according to the detected pathogens.The top five detected bacteria were divided into Pseudomonas aeruginosa group,Acinetobacter baumannii group,Klebsiella pneumoniae group,Streptococcus pneumoniae group and Candida albicans group.There was no statistical significance in the concentrations of IL-6,TNF-α and s IgA among the five groups(P > 0.05).(3)Patients with lower respiratory tract infection were grouped by pathogen type,and there was no statistical significance in the concentrations of IL-6,TNF-α and s IgA in gram-positive bacteria group,Gram-negative bacteria group,atypical pathogen group and fungus group(P > 0.05).(4)According to the statistics of patients with lower respiratory tract infection by disease classification,the il-6 concentration of pneumonia,chronic obstructive pulmonary disease combined with infection and severe pneumonia group was compared,the difference was statistically significant(P < 0.05),and the IL-6concentration of severe pneumonia was higher than that of pneumonia and chronic obstructive pulmonary disease combined with infection.The concentration of IL-6 in the pneumonia group was higher than that in the copd group.The results showed that there was no significant difference between pneumonia and chronic obstructive pulmonary disease complicated with infection(P > 0.05).There were statistically significant differences in TNF-α concentrations between pneumonia and severe pneumonia,as well as between chronic obstructive pulmonary disease and severe pneumonia(P < 0.05),and TNF-α concentrations in severe pneumonia were higher than those in pneumonia and chronic obstructive pulmonary disease.There was no significant difference in s IgA concentration among the three groups(P > 0.05).Conclusion The concentration of IL-6 and TNF-α in BALF can be used to ev aluate the severity of the disease of patients with lower respiratory tract infecti on,which is helpful for the prognosis of patients.The role of s IgA in the eva luation of patients with lower respiratory tract infection needs further study.