Clinical Outcomes and Bacterial Characteristics of Carbapenem-resistant Acinetobacter baumannii Among Patients From Different Global Regions

Multi-Drug Resistant Organism Network Investigators

Research output: Contribution to journalArticlepeer-review

6 Scopus citations


BACKGROUND: Carbapenem-resistant Acinetobacter baumannii (CRAb) is 1 of the most problematic antimicrobial-resistant bacteria. We sought to elucidate the international epidemiology and clinical impact of CRAb.

METHODS: In a prospective observational cohort study, 842 hospitalized patients with a clinical CRAb culture were enrolled at 46 hospitals in five global regions between 2017 and 2019. The primary outcome was all-cause mortality at 30 days from the index culture. The strains underwent whole-genome analysis.

RESULTS: Of 842 cases, 536 (64%) represented infection. By 30 days, 128 (24%) of the infected patients died, ranging from 1 (6%) of 18 in Australia-Singapore to 54 (25%) of 216 in the United States and 24 (49%) of 49 in South-Central America, whereas 42 (14%) of non-infected patients died. Bacteremia was associated with a higher risk of death compared with other types of infection (40 [42%] of 96 vs 88 [20%] of 440). In a multivariable logistic regression analysis, bloodstream infection and higher age-adjusted Charlson comorbidity index were independently associated with 30-day mortality. Clonal group 2 (CG2) strains predominated except in South-Central America, ranging from 216 (59%) of 369 in the United States to 282 (97%) of 291 in China. Acquired carbapenemase genes were carried by 769 (91%) of the 842 isolates. CG2 strains were significantly associated with higher levels of meropenem resistance, yet non-CG2 cases were over-represented among the deaths compared with CG2 cases.

CONCLUSIONS: CRAb infection types and clinical outcomes differed significantly across regions. Although CG2 strains remained predominant, non-CG2 strains were associated with higher mortality. Clinical Trials Registration. NCT03646227.

Original languageEnglish (US)
Pages (from-to)248-258
Number of pages11
JournalClinical infectious diseases : an official publication of the Infectious Diseases Society of America
Issue number2
Early online dateSep 20 2023
StatePublished - Feb 15 2024


  • carbapenem-resistant Acinetobacter baumannii
  • clinical impact
  • international epidemiology
  • Microbial Sensitivity Tests
  • Carbapenems/pharmacology
  • Acinetobacter baumannii/genetics
  • Bacterial Proteins/genetics
  • Prospective Studies
  • Humans
  • Acinetobacter Infections/drug therapy
  • beta-Lactamases/genetics
  • Anti-Bacterial Agents/pharmacology

ASJC Scopus subject areas

  • Microbiology (medical)
  • Infectious Diseases


Dive into the research topics of 'Clinical Outcomes and Bacterial Characteristics of Carbapenem-resistant Acinetobacter baumannii Among Patients From Different Global Regions'. Together they form a unique fingerprint.

Cite this