Dataset Information

Risk and Prognostic Factors for Multidrug-Resistant Acinetobacter Baumannii Complex Bacteremia: A Retrospective Study in a Tertiary Hospital of West China.

ABSTRACT:

Background

The increasing prevalence and mortality of multidrug-resistant (MDR) Acinetobacter baumannii complex-associated infections, especially bacteremia, in health care settings poses a great threat to public health. We proceeded to investigate the risk and prognostic factors for MDR A. baumannii complex bacteremia in mainland China.

Methods

This retrospective study was conducted at West China Hospital from January 2009 to December 2013. Using a computer-assisted microbiology laboratory database, patients with MDR A. baumannii complex bacteremia were included as the case group, while those infected with non-MDR A. baumannii complex were selected as the control group. The clinical data were collected and analyzed.

Results

There were 241 non-duplicated A. baumannii complex blood isolates identified in our research, with the overall rate of multidrug resistance reaching 75.52% over the past five years. Using multivariate logistic analysis, being in the intensive care unit (ICU) (adjusted odds ratio [aOR], 5.84; 95% confidence interval [CI], 1.67-20.44), increased Pittsburgh bacteremia score (aOR, 6.55; 95% CI, 1.27-33.70) and use of carbapenem (aOR, 8.90; 95% CI, 1.71-46.30) were independent risk factors for MDR acquisition among patients with A. baumannii complex bacteremia. Older age (aOR, 1.02; 95% CI, 1.00-1.04), being post-transplantation (aOR, 5.21; 95% CI, 1.13-24.04), having a higher Pittsburgh bacteremia score (aOR, 2.19; 95% CI, 1.08-4.47) and having a lower level of albumin (aOR, 0.93; 95% CI, 0.88-0.99) were identified as independent risk factors for 30-day mortality in patients with MDR A. baumannii complex bacteremia.

Conclusion

In conclusion, our research revealed the risk factors associated with acquisition of and mortality from MDR A. baumannii complex bacteremia, which may be used to prioritize infection control practices and prognostic evaluations.

SUBMITTER: Liu Q

PROVIDER: S-EPMC4471170 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Publications

Risk and Prognostic Factors for Multidrug-Resistant Acinetobacter Baumannii Complex Bacteremia: A Retrospective Study in a Tertiary Hospital of West China.

Liu Qianqian Q Li Wenzhang W Du Xinmiao X Li Weijing W Zhong Taiqing T Tang Yin Y Feng Yulin Y Tao Chuanmin C Xie Yi Y

PloS one 20150617 6

<h4>Background</h4>The increasing prevalence and mortality of multidrug-resistant (MDR) Acinetobacter baumannii complex-associated infections, especially bacteremia, in health care settings poses a great threat to public health. We proceeded to investigate the risk and prognostic factors for MDR A. baumannii complex bacteremia in mainland China.<h4>Methods</h4>This retrospective study was conducted at West China Hospital from January 2009 to December 2013. Using a computer-assisted microbiology ...[more]

PMID: 26083415

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Project description:Acinetobacter baumannii is an important nosocomial pathogen, which is multidrug resistant (MDR). Acinetobacter baumannii has become a major threat to public health worldwide due to its ability to easily acquire resistant genes. In order to analyze its epidemiology characteristics and the genetic evolution, A. baumannii isolates obtained from a Chinese tertiary hospital in the past 12 years (2008-2019), 295 isolates of non-repetitive A. baumannii, were recovered from patients and wards environments. The resistance genes were analyzed using antimicrobial susceptibility testing. The genetic relatedness of 295 isolates was identified by multilocus sequence typing (MLST) and eBURST analysis. It was found that the antibiotic-resistant and carbapenemase-resistant genes of all the 295 MDR A. baumannii in the hospital have not changed significantly over the past 12 years; all of them were resistant to multiple antibiotics except the polymyxin E and tigecycline. The results of drug-resistant genes showed that the detection rates of carbapenemase-resistant genes bla OXA-23, bla TEM-1, and bla OXA-66 were 97.6, 75.3, and 71.9%, respectively, which were detected almost every year from 2008 to 2019. Additionally, 16s rRNA methylation enzyme gene armA, aminoglycoside-resistant gene ant(3")-I, and class I integrase gene could also have a high positive rate. By MLST, these isolates were assigned to 12 sequence types (STs), including ST369, ST208, ST195, ST191, ST368, ST530, ST469, ST451, ST229, ST381, ST543, and ST1176. eBURST analysis showed that 9 STs with ST208 as the founder genotype belonged to Group 1 except for ST229, ST530, and ST1176. Therefore, most MDR A. baumannii isolates had a relatively close genetic relationship. Notably, the predominant ST208 and ST369 at the early stage changed to ST451 in 2019, indicating that the complex and diverse genetic background of the prevalence of A. baumannii isolates in the hospital. Overall, further epidemiological surveillance and genetic evolution analysis of A. baumannii are required, which can provide new strategies for the prevention and control of A. baumannii infections.

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Dataset Information

Risk and Prognostic Factors for Multidrug-Resistant Acinetobacter Baumannii Complex Bacteremia: A Retrospective Study in a Tertiary Hospital of West China.

Background

Methods

Results

Conclusion

Publications

Risk and Prognostic Factors for Multidrug-Resistant Acinetobacter Baumannii Complex Bacteremia: A Retrospective Study in a Tertiary Hospital of West China.

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