Risk factors for pneumonia caused by antimicrobial drug-resistant or drug-sensitive Acinetobacter baumannii infections: A retrospective study

Abstract

Acinetobacter baumannii (AB) is one of the major types of infection in hospitalized patients. The development of AB resistance is becoming a global clinical challenge. To assist in the clinical management of AB-induced pneumonia, we designed the present retrospective observational study to investigate the risk factors for antimicrobial drug-resistant/-sensitive AB infections.A total of 214 individuals were reviewed, in which 100 and 55 pneumonia patients were infected with drug-resistant and drug-sensitive AB, respectively. Fifty-nine pneumonia patients without AB infection served as a control group. Age, sex, duration of hospital stay, prior surgery history, the presence of coinfection and companion diseases, routine blood test results, and immunogenicity were recorded. Logistic regression was performed to identify risk factors of AB infections.Multivariate analysis revealed that long duration of hospital stay (odds ratio = 1.091 [95% CI: 1.010-1.178], P = .027) and the absence of coinfection (odds ratio = 0.507 [95% CI: 0.265-0.970], P = .040) were independent risk factors for AB infections. Same pattern of risk factors was identified for the drug-sensitive group (long duration of hospital stay: odds ratio = 1.119 [95% CI: 1.016-1.232], P = .022; absence of coinfection: odds ratio = 0.328 [95% CI: 0.135-0.797], P = .014), while high blood urea nitrogen (odds ratio: 1.382 [95% CI: 1.042-1.833], P = .025) was the only significant risk factor for drug-resistant AB infection.Long duration of hospital stay and the absence of coinfection might predict AB infections in hospitalized patients. Antimicrobial drug-resistant and drug-sensitive AB infections possess different risk factor profiles. A poor kidney function may be predictive of drug-resistant AB infection. Further prospective studies are required to validate our findings.