Risk Factors And Drug Resistance Of Bacterial Positive Sputum Culture In Acute Exacerbation Of Chronic Obstructive Pulmonary Disease

Objective:To retrospectively analyze the sputum culture results of the second Department of the First Hospital of Jilin University in acute exacerbation of chronic obstructive pulmonary disease,to understand the risk factors of positive sputum culture in patients with acute exacerbation of chronic obstructive pulmonary disease,to guide clinical empirical use of antibiotics and to prevent the occurrence of acute exacerbation more effectively.Methods:824 patients with acute exacerbation of chronic obstructive pulmonary disease?AECOPD?diagnosed in the second Respiratory Department of the First Hospital of Jilin University from 2016 to 2018were collected.599 patients were excluded.225 patients were enrolled,including 132 males and 93 females,aged 42-87 years?average age67.77±9.72 years?.General data of patients were recorded in detail.Clinical data of patients were collected,including sputum culture,PaO₂ and PaCO₂,FEV₁%and FEV₁/FVC of pulmonary function,CRP,white blood cell count and neutrophil percentage,smoking history,bronchiectasis,hospital stay.All patients met the following exclusion criteria:?1?severe cardiac insufficiency;?2?other pulmonary diseases such as bronchiectasis?except COPD with bronchiectasis?,asthma,tuberculosis,interstitial lung disease;?3?malignant tumors;autoimmune diseases;patients with severe hepatorenal insufficiency;?4?recent severe surgery,trauma,infection;?5?Complicated with extrapulmonary infection.?6?To isolate fungi?such as aspergillus,candida?or Mycobacterium tuberculosis from sputum culture.The patients were divided into three groups:?1?sputum culture positive group?drug sensitive group,drug resistance group?;?2?sputum culture negative group?patients who did not use antibiotics 7 days before admission?.To analyze and compare clinical characteristics of sputum culture respectively.Results:1.The results of sputum culture were negative in 115 cases?51.1%?and positive in 110 cases?48.9%?and 85 cases in sensitive group?37.8%?and resistant group 25 cases?11.1%?.2.Sputum culture negative group:66 males and 49 females,with an average age of 67.30±9.63 years.Sputum culture positive group:sensitive group:52 males,33 females,average age 67.73±9.61 years;drug resistant group:13 males,12 females,average age 70.04±10.54 years.3.Among 110 sputum culture positive patients,90.0%?99/110?were Gram-negative bacteria,including 33.6%?37/110?of Klebsiella pneumoniae,20.0%?22/110?of Pseudomonas aeruginosa,6.3%?7/110?of Acinetobacter baumannii,5.5%?6/110?of Klebsiella acidogenicus,4.5%?5/110?of Escherichia coli,3.6%?4/110?of Serratia marcescens,11.8%?13/110?of other Gram-negative bacteria.Gram-positive bacteria accounted for 1.8%?2/110?,including 0.9%?1/110?Staphylococcus aureus,0.9%?1/110?Streptococcus pneumoniae;The polyinfection accounted for8.2%?9/110?.4.There was no statistical significant in sex,age,PaO₂ and PaCO₂,FEV₁%predicted value and FEV₁/FVC between the negative group and the positive group?p>0.05?.Klebsiella pneumoniae subspecies is the most common microorganism in sputum of patients with AECOPD without bronchiectasis,and Pseudomonas aeruginosa infection in sputum of patients with AECOPD with bronchiectasis is the most common microorganism.Smoking history and bronchiectasis were risk factors for positive sputum culture?P<0.05?.5.There were no statistical significant in gender,age,PaO₂ and PaCO₂,FEV₁%predicted value and FEV₁/FVC between the drug sensitive group and the drug resistant group?p>0.05?.The PaO₂ in the drug resistant group was lower than that in the sensitive group?p<0.05?.Compared with non-smoking patients,smoking patients were less likely to develop drug resistance microorganisms,and the difference was statistically significant?p<0.05?.There was no statistical significant between bronchiectasis and drug resistance microorganisms between two groups?P>0.05?.6.Compared with sputum culture negative group,C-reactive protein,blood routine white blood cell count and neutrophil percentage in sputum culture positive group were higher than those in sputum culture negative group,and the difference was statistically significant?p<0.05?.The increase of C-reactive protein,white blood cell count and neutrophil percentage can predict bacterial positive sputum culture,but the accuracy is low.The AUC values were 0.59,0.58 and 0.58,respectively.Conclusion:1.Bronchiectasis and smoking history are risk factors for airway microorganisms in patients with acute exacerbation of chronic obstructive pulmonary disease,which can be used as evidence for empirical use of antibiotics.2.The condition of patients with microorganisms drug resistance is more serious.3.The increase of C-reactive protein,white blood cell count and neutrophil percentage can predict bacterial positive sputum culture,but the accuracy is low.CRP is better than the percentage of white blood cells and neutrophils in predicting bacteria.