Impact of Difficult-to-Treat Resistance in Gram-negative Bacteremia on Mortality: Retrospective Analysis of Nationwide Surveillance Data.

Abstract

BACKGROUND:

Clinically relevant categorization of antimicrobial resistance is critical to mitigating the threat it poses. Difficult-to-treat resistance (DTR) is a recently proposed category defined as nonsusceptibility to all first-line antibiotic agents.

METHODS:

A retrospective study was conducted with nonduplicate cases of gram-negative bloodstream infection (GNBSI) caused by 4 major taxa (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter species) identified from a nationwide surveillance database. DTR was defined as nonsusceptibility to all the β-lactams and fluoroquinolones tested. Patient characteristics and mortality were compared between DTR GNBSI and GNBSI caused by carbapenem-resistant but not DTR and extended-spectrum cephalosporin-resistant but not DTR isolates using Centers for Disease Control and Prevention definitions. Adjusted odds ratios (aORs) for 30-day in-hospital mortality were examined for DTR in overall and in propensity score-matched cohorts.

RESULTS:

A total of 1167 episodes of monomicrobial GNBSI were identified, and 147 (12.6%) of the isolates were DTR. The majority of DTR isolates were Acinetobacter species (79.6%) and P. aeruginosa (17.7%). DTR infections were associated with previous antibiotic use, healthcare contact, ventilator use, and lower respiratory tract infection. Crude mortality for GNBSI caused by DTR was 50.3%. A multivariable model showed that only DTR, but not other categories, was significantly associated with mortality (adjusted odds ratio [aOR], 3.58 [95% confidence interval {CI}, 1.27-10.19]). DTR was also a significant predictor for mortality in the analysis of propensity score-matched cohorts (aOR, 3.48 [95% CI, 1.82-6.79]).

CONCLUSIONS:

In patients with GNBSI, DTR was associated with higher mortality than those in other resistance categories. Our findings suggest that DTR could be useful for surveillance and prognostication.

• Authors: Kyungmin Huh, Doo Ryeon Chung, Young Eun Ha, Jae-Hoon Ko, Si-Ho Kim, Min-Ji Kim, Hee Jae Huh, Nam Yong Lee, Sun Young Cho, Cheol-In Kang, Kyong Ran Peck, Jae-Hoon Song, Korean Antimicrobial Resistance Surveillance Network (KARS-Net) Investigators
• Journal: Clinical infectious diseases : an official publication of the Infectious Diseases Society of America (Clin Infect Dis) Vol. 71 Issue 9 Pg. e487-e496 (12 03 2020) ISSN: 1537-6591 [Electronic] United States
• PMID: 31994704 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: [email protected].

Chemical References

• Anti-Bacterial Agents
• Carbapenems
• Fluoroquinolones

Topics

• Anti-Bacterial Agents (therapeutic use)
• Bacteremia (drug therapy, epidemiology)
• Carbapenems
• Drug Resistance, Bacterial
• Fluoroquinolones
• Gram-Negative Bacteria
• Gram-Negative Bacterial Infections (drug therapy, epidemiology)
• Humans
• Microbial Sensitivity Tests
• Retrospective Studies