Multi-center Investigations Of Pathogenic Epidemiology And Drug Resistance Genes In Patients With Acute Exacerbations Of Chronic Obstructive Pulmonary Disease

OBJECTIVES: To search for optimized antimicrobial treatments of acuteexacerbation of chronic obstructive pulmonary disease (AECOPD) through observingthe prevalence of various pathogens, evaluating clinical characters of AECOPD andefficiency of current treatments, and analyzing antimicrobial resistance geneexpression patterns.METHODS: A prospective observational study was conducted in11hospitals inBeijing from June2013to Jan2014. A total of326AECOPD patients were enrolledand142bacterial isolates were collected from109sputum samples. Bacteria sputumculture and antimicrobial susceptibility testing were performed with these samples.Clinical characteristics were analyzed of various pathogen infections. Antimicrobialresistance gene profiles were analyzed with PCR.RESULTS: A total of326patients were enrolled with207male (63.5%) and119female (36.5%). Median age of the patients was75.7years (range,46–100yr). Initialempirical antimicrobials used for treatment of AECOPD before admission included2nd,3rd and4th generation of cephalosporins, quinolones or the combinationsbetween cephalosporins and quinolones.44.5%of cases applied empiricalantimicrobials before admissions. There was no difference in clinical outcomes ofpatients by receiving initial empirical therapy. Pathogens were detected in sputumsamples from109out of326patients (33.4%). Five major bacterial isolates fromAECOPD patients were Klebsiella pneumoniae (17.6%), Pseudomonas aeruginosa(15.5%), Acinetobacter Bauman(9.2%); Mycoplasma pneumonia(6.3%),Staphylococcus aureus(4.2%). The enrolled patients were divided into xxxx groups:names of the treatments. Compared with other treatments, antibiotics levofloxacin,moxifloxacin and piperacillin/enzyme inhibitor treatments reduced in-hospitalduration and were more cost efficient. The most frequent identified gram negative bacteria in the sputum culture were Klebsiella pneumonia, Pseudomonas aeruginosa,Escherichia coli, and Acinetobacter. In these isolates, the antibiotic with the lowestresistance rate were amikacin, cefoperazone/Sulbactam, piperacillin/tazobactam,cefepime. Resistance to carbapenems was the highest (%). A large of portion of K.pneumoniae isolates (%) which were resistant to to β-lactam antibiotics expressedSHV β-lactamase.78.6%of Acinetobacter bauman expressed DNA gene.CONCLUSIONS:The antibiotic resistance rate is higher than ever. Compared withother antibiotics, levofloxacin, moxifloxacin and piperacillin/enzyme inhibitor havelower cost, no statistically significant differences in the prognosis. We should haveetiological examinationas soon as possible after hospitalization.Differentantimicrobial drugs have different resistance mechanism. Correct choice of antibioticsis the key to prevent the drug resistance. Screening for resistance genes may provide atherapeutic direction for antibiotic selection.