Objective To investigate the relationship between serum amyloid A(SAA),interleukin-10(IL-10),interleukin-21(IL-21)levels and the first acute exacerbation in patients with chronic obstructive pulmo-nary disease(COPD)with pneumothorax.Methods A total of 102 patients with stable COPD complicated with pneumothorax admitted to the hospital from January 2020 to January 2023 were selected.They were treated with closed thoracic drainage,anti-inflammatory,antiasthmatic,expectorant,and high-flow nasal hu-midification oxygen therapy(HFNC).The patients were divided into two groups according to whether they had the first acute exacerbation within 1 year after treatment,the first acute exacerbation group(32 patients had the first acute exacerbation within 1 year of follow-up)and the non-first acute exacerbation group(70 pa-tients had no first acute exacerbation within 1 year of follow-up).Serum SAA,IL-10 and IL-21 levels and blood gas indexes were compared between the two groups after treatment.Multivariate Logistic regression a-nalysis was used to analyze the influencing factors of the first acute exacerbation after HFNC treatment.The receiver operating characteristic(ROC)curve was used to analyze the predictive value of serum SAA,IL-10 and IL-21 levels after treatment for the first acute exacerbation of COPD patients with pneumothorax.Results There were significant differences in hypoproteinemia,smoking,underlying diseases,forced vital ca-pacity(FVC),forced expiratory volume in one second(FEV1)as a percentage of predicted value(FEV1%),FEV1 to FVC ratio(FEV1/FVC),arterial partial pressure of oxygen(PaO2),arterial partial pressure of car-bon dioxide(PaCO2),SAA,IL-10,IL-21 between the two groups(P<0.05).Multivariate Logistic regression analysis showed that hypoproteinemia,smoking,underlying diseases,PaCO2,SAA,IL-10 and IL-21 were the risk factors for the first acute exacerbation after HFNC treatment(P<0.05).FVC,FEV1%,FEV1/FVC and PaO2 were protective factors for the first acute exacerbation after treatment(P<0.05).ROC curve results showed that the area under the curve(AUC)of SAA,IL-10 and IL-21 levels after treatment to predict the first acute exacerbation of COPD patients with pneumothorax was 0.755,0.726 and 0.674,respectively.When the cut-off values of SAA,IL-10 and IL-21 were 171.06 g/L,26.46 pg/mL and 244.79 pg/mL,the sen-sitivity was 76.51%,60.84%and 56.90%,and the specificity was 66.73%,74.49%and 74.52%,respective-ly.The AUC of combined prediction was 0.860,the sensitivity was 80.44%,and the specificity was 76.51%.Conclusion The serum SAA,IL-10 and IL-21 levels in COPD patients with pneumothorax have certain pre-dictive value for the first acute exacerbation of COPD patients with pneumothorax.

Pseudomonas aeruginosa is a common pathogen of respiratory infections. The conventional diagnostic methods for Pseudomonas aeruginosa have certain weakness, for example, sputum culture is time-consuming and of low sensitivity; and polymerase chain reaction cannot be popularized clinically due to its high cost. Meanwhile, detection of volatile organic compounds is a sensitive, rapid, portable and inexpensive diagnostic method. This review focuses on the detection of volatile organic compounds in the diagnosis of Pseudomonas aeruginosa respiratory infection, discusses the existing problems, and puts forward relevant suggestions to provide reference for clinical application and future researches.