Clinical epidemiology of carbapenem-resistant gram-negative sepsis among hospitalized patients: Shifting burden of disease?

Am J Infect Control. 2018 Oct;46(10):1092-1096. doi: 10.1016/j.ajic.2018.03.013. Epub 2018 Apr 26.

Abstract

Background: Infections caused by carbapenem-resistant gram-negative bacilli are an emerging public health threat. However, there is a paucity of data examining comparative incidence rates, risk factors, and outcomes in this population.

Methods: This single-center retrospective cohort study was conducted at an urban tertiary-care academic medical center. We included patients admitted from 2012 to 2015 who met the following criteria: i) age ≥ 18 years; and ii) culture positive for carbapenem-resistant Enterobacteriaceae (CRE) or carbapenem-resistant non-Enterobacteriaceae (CRNE) from any site. Exclusion criteria were: i) < 2 systemic inflammatory response criteria; ii) cystic fibrosis; and iii) no targeted treatment. We evaluated hospital survival by Cox regression and year-by-year differences in the distribution of cases by the Cochran-Armitage test.

Results: 448 patients were analyzed (CRE, n = 111 [24.8%]; CRNE, n = 337 [75.2%]). CRE sepsis cases increased significantly over the study period (P <.001), driven primarily by increasing incidence of Enterobacter spp. infection (P = .004). No difference was observed in hospital survival between patients with CRE versus CRNE sepsis (hazard ratio [HR], 1.29; 95% confidence interval [CI], 0.83-2.02; P = .285), even after adjusting for confounding factors (adjusted HR, 1.08; 95% CI, 0.62-1.87; P = .799).

Conclusions: Clinical outcomes did not differ between patients with CRE versus CRNE sepsis. Dramatic increases in CRE, particularly Enterobacter spp., appear to be causing a shift in the burden of clinically significant carbapenem-resistant gram-negative infection.

Keywords: Carbapenem resistance; Carbapenem-resistant Enterobacteriaceae; Multidrug resistance; Pseudomonas aeruginosa; Sepsis.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Anti-Bacterial Agents / classification
  • Anti-Bacterial Agents / pharmacology*
  • Carbapenems / pharmacology*
  • Drug Resistance, Bacterial
  • Gram-Negative Bacteria / drug effects*
  • Gram-Negative Bacterial Infections / microbiology*
  • Humans
  • Inpatients*
  • Sepsis / microbiology*

Substances

  • Anti-Bacterial Agents
  • Carbapenems