A Comparative Study Of Patients With Acute Exacerbation Of Chronic Obstructive Pulmonary Disease At Different Eosinophil Levels

Objective:To compare the therapeutic effects of patients with acute exacerbations of chronic obstructive pulmonary disease with different peripheral blood eosinophil levels after hospitalization.Method:Patients with acute exacerbation of chronic obstructive pulmonary disease were divided into the peripheral blood eosinophil group（the EOS group）and the peripheral blood eosinophil control group（the control group）,ues the threshold of peripheral blood eosinophils>300/uL as cut off value.From December 2017 to December 2018,32 patients with acute exacerbation of chronic obstructive pulmonary disease（12 patients in the EOS group）were recruited in the department of respiratory medicine,First Affiliated Hospital of Guangxi Medical University,all recruited patients with acute exacerbation of chronic obstructive pulmonary disease were treated with corticosteroids and antibiotics during hospitalization.The study included:（1）Clinical data of two groups of patients with acute exacerbations of chronic obstructive pulmonary disease were recorded,including basic information,hospitalized date,routine blood test,blood gas test and so forth.Peripheral blood samples of patients with acute exacerbation of chronic obstructive pulmonary disease were collected on the first day and the seventh days of hospitalization.Using a portable lung function instrument performed lung function testing for patients with acute exacerbation of chronic obstructive pulmonary disease on the first day and the seventh days of hospitalization,and the CAT tests were performed at the same time;（2）Peripheral blood samples from the two groups of patients with acute exacerbation of chronic obstructive pulmonary disease were collected for serum extraction,and the expression levels of interleukin 8（IL-8）,interleukin 6（IL-6）,and tumor necrosis factor alpha（TNF-a）in the peripheral blood of the patients on the first day and the seventh day of hospitalization were detected by enzyme-linked immunosorbent assay（ELISA）;（3）Under aseptic conditions in the laboratory,peripheral blood mononuclear cells（PBMCs）were isolated from the peripheral blood of two groups of patients with acute exacerbation of chronic obstructive pulmonary disease by using Lymphocyte separation solution,these peripheral blood mononuclear cells（PBMCs）were put in the CO₂ incubator and intervention with different concentrations of dexamethasone(the control group with 0 mol/L dexamethasone,and the intervention group with 10^-6,10^-7,10^-8,10^-9,10^-10,10^-11,10^-12mol/L dexamethasone),then using TNF-αstimulation,the supernatant obtained after centrifugation was stored in-80℃refrigerator,after all the specimens were collected,detected the expression levels of IL-8 by ELISA.The expression levels of IL-8 in peripheral blood mononuclear cells of two groups of patients with chronic obstructive pulmonary disease were detected after receiving different concentrations of dexamethasone intervention,then the rate of inhibition of interleukin-8 in patients with different concentrations of dexamethasone intervention were obtained.Calculate the half-maximal inhibitory concentration of dexamethasone to determine the concentration when glucocorticoids exert 50%anti-inflammatory effects,in order to reflect the sensitivity of the two groups of patients to glucocorticoids;（4）Recorded the time of hospital discharge of patients with acute exacerbation of chronic obstructive pulmonary disease in the two groups,so as to compare the hospitalization time of patients with acute exacerbation of chronic obstructive pulmonary disease in the EOS group and the control group.Result:（1）In the two groups of patients with acute exacerbation of chronic obstructive pulmonary disease,there were no statistically significant differences between the basic information and clinical examination at the beginning of hospitalization,P>0.05.Compared with the first day of hospitalization,the CAT scores,the PaO₂ and PaCO₂ of blood gas test,the FEV1%pred and FEV1/FVC of pulmonary function examination were improved in both groups on the seventh days of hospitalization,the differences were statistically significant,P<0.05;（2）There were no differences in the expression levels of IL-8,IL-6 and TNF-αbetween the two groups on the first day of hospitalization,P>0.05.Compared with the first day of hospitalization,the expression levels of IL-8,IL-6 and TNF-αin the EOS group and the control group on the seventh days of hospitalization were decreased,the differences were statistically significant,P<0.05.Compared with the control group,the EOS group’s Il-8 and Il-6 on the seventh days of hospitalization were both at lower expression levels and the differences were statistically significant,P<0.05;（3）The Eos group’s Interleukin-8 inhibition rate on the first day of hospitalization compared with the control group’s Interleukin-8 inhibition rate on the first day of hospitalization,the difference was not statistically significant,P>0.05;The EOS group’s Interleukin-8 inhibition rate on the seventh days of hospitalization was higher than the control group’s Interleukin-8 inhibition rate on the seventh days of hospitalization,and at 10^-8-10^-6mol/L of dexamethasone concentration,the difference was statistically significant,P<0.05;（4）According to the inhibition rate of interleukin 8（IL-8）in each group,the half-inhibitory concentration of dexamethasone（IC50-DEX）in each group was calculated,the EOS group’s IC50-DEX on the first day of hospitalization compared with the control group’s IC50-DEX on the first day of hospitalization,the difference was not statistically significant,P>0.05;The EOS group’s IC50-DEX on the seventh days of hospitalization compared with the control group’s IC50-DEX on the seventh days of hospitalization,the EOS group’s IC50-DEX had a lower level than the control group’s IC50-DEX on the seventh days of hospitalization,the difference was statistically significant,P<0.05;（5）The comparison of the length of hospital stay between two groups of patients with acute exacerbations of chronic obstructive pulmonary disease was shown that,the EOS group had a reduced length of hospital stay compared with the control group,and the difference was statistically significant,P<0.05.Conclusion:Patients with acute exacerbation of chronic obstructive pulmonary disease whose peripheral blood eosinophils with absolute count>300/uL compared with patients with acute exacerbation of chronic obstructive pulmonary disease whose peripheral blood eosinophils with absolute count≤300/uL,the expression of inflammatory cytokine was expressed at lower levels and glucocorticoid resistance was milder,the length of hospital stay was shortened.