Pathogens and drug resistance analysis in different groups of patients with acute exacerbation of chronic obstructive pulmonary disease

Objective To explore pathogens and their drug resistance in different groups of patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD) and provide guidance for clinical empiric antibiotic treatment. Methods Five hundred and thirty-six patients with AECOPD were selected in our hospital from 2010 to 2014. After comprehensive assessment classification according to GOLD(2013),all patients were divided into A,B,C and D four groups. Bacterial culture and drug susceptibility testing were performed on sputum specimens of 536 cases of patients. Results Three hundred and sixty-eight pathogens were isolated from 311 AECOPD patients of a total of 526(58.02%), 45 patients were isolated two or more than two pathogens. One hundred and fifteen pathogens were Grampositive bacteria, most of which were Staphylococcus aureus,Streptococcus pneumoniae. Two hundred and twenty-four Gram-negative bacteria were isolated, and most of which were Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Haemophilus influenzae. Twenty-nine fungi were detected. Streptococcus pneumoniae and Staphylococcus aureus were predominant in group A while Haemophilus influenzae and Moraxella catarrhalis in group B.Klebsiella pneumoniae and Escherichia coli were most frequent,in group D Pseudomonas aeruginosa,Klebsiella pneumoniae,Escherichia coli were the most frequent.Susceptibility testing results showed that gram-positive bacteria were highly resistant to azithromycin,high cotrimoxazole,erythromycin,amoxicillin/clavulanic acid,ceftriaxone.No vancomycin and Linezolid resistant strain was found in gram-positive isolates.Carbapenem-resistant Enterobacteriaceae were increased, these bacteria were also resisted to other antibiotics we usually use. Pseudomonas aeruginosa showed a high resistance rate to imipenem of 35.6%. Conclusions Pathogens distribution was different in different groups of acute exacerbation of chronic obstructive pulmonary disease and the resistance of bacteria to antibiotics was serious. We should use antibiotics reasonably according to the comprehensive assessment classification of patients and surveillance of bacterial resistance. Key words: Chronic obstructive pulmonary disease; Acute exacerbation; Bacteria; Resistance; Comprehensive assessment classification