Abstract: Objective To explore the risk factor of Acinetobacter baumannii(AB)infection and drug resistance in patients with chronic obstructive pulmonary disease(COPD)in order to provide a theoretical basis for treating AB infection in COPD patients. Methods The clinical data of inpatients treated during 2012 and 2015 were collected from departments of respiratory and respiratory intensive care unit, and 308 AB positive patients were selected according to the exclusion criteria. Drug-resistant bacteria and drug resistance were detected in 308 AB positive cases and 91 COPD cases with AB. A case control study was performed in 144 COPD patients, including 72 AB positive and 72 AB negative cases. 山 东 大 学 学 报 (医 学 版)57卷9期 -张宁,等.慢阻肺患者感染鲍曼不动杆菌危险因素及耐药性分析 \=- The risk factors associated with AB infection were determined with binary logistic regression analysis. Results (1) Single factor analysis showed that age, recent history of hospitalization, history of glucocorticoid and antibiotics use, invasive operations, chronic diseases, classification of lung function and frequency of exacerbations were statistically significant (P<0.05). Multivariate Logistic regression showed that invasive operation (OR=3.725, 95% CI=2.642-9.534), recent history of hospitalization (OR=3.417, 95%CI=1.412-8.515), classification of lung function (OR=2.835, 95%CI=1.012-9.853), history of glucocorticoid use (OR=2.815, 95%CI=1.328-9.045), chronic disease (OR=2.136, 95%CI=1.023-8.146), history of antibiotic use(OR=2.326, 95%CI=1.145-7.134), frequency of exacerbations (OR=2.823, 95%CI=1.012-9.853), age (OR=1.756, 95%CI=1.003-7.035) were independent risk factors of AB infection (P<0.05). (2) Drug resistance tests of AB positive patients showed that cefepime had the highest drug resistance rate(79.2%), while tegacycline had the lowest drug resistance rate(20.1%). (3) Compared to non-COPD patients, COPD patients with AB had higher resistance rates to imipenem(86.8% vs 59.4%), cefepime(93.4% vs 73.2%), levofloxacin(82.4% vs 57.6%), cefoperazone sulbactam(49.4% vs 29.0%)and tegacycline(27.5% vs 17.1%). The differences were statistically significant (P<0.05). Conclusion Chronic diseases, invasive operation, recent history of hospitalization, history of glucocorticoid and antibiotic use and classification of lung function are independent risk factors for COPD patients infected with AB. Compared with non-COPD patients with lower respiratory tract infection of AB, COPD patients with AB have higher resistance rate to common clinical antibiotics.

Key words: Chronic obstructive pulmonary disease, Acinetobacter baumannii, Drug resistance, Risk factors, Multivariate logistic regression analysis