Characteristics of community-acquired carbapenem-resistant Enterobacterales

J Antimicrob Chemother. 2022 Sep 30;77(10):2763-2771. doi: 10.1093/jac/dkac239.


Background: Community-acquired carbapenem-resistant Enterobacterales (CA-CRE) are an important threat.

Methods: In CRACKLE-2, we defined patients with CA-CRE as admitted from home, without pre-existing conditions, and a positive culture within 48 h of admission. Healthcare-associated CRE (HA-CRE) were those with the lowest likelihood of community acquisition, not admitted from home and cultured >48 h after admission. Specific genetic markers in carbapenemase-producing Klebsiella pneumoniae were evaluated through random forest modelling.

Results: CA-CRE and HA-CRE were detected in 83 (10%) and 208 (26%) of 807 patients. No significant differences were observed in bacterial species or strain type distribution. K. pneumoniae (204/291, 70%) was the most common CRE species, of these 184/204 (90%) were carbapenemase producers (CPKP). The top three genetic markers in random forest models were kpi_SA15, fimE, and kpfC. Of these, kpi_SA15 (which encodes a chaperone/usher system) was positively associated (OR 3.14, 95% CI 1.13-8.87, P = 0.026), and kpfC negatively associated (OR 0.21, 95% CI 0.05-0.72, P = 0.015) with CA-CPKP.

Conclusions: Ten percent of CDC-defined CRE were CA. The true proportion of CA-CRE in hospitalized patients is likely lower as patients may have had unrecorded prior healthcare exposure. The kpi_SA15 operon was associated with the CA phenotype.

Publication types

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

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Anti-Bacterial Agents / therapeutic use
  • Bacterial Proteins / genetics
  • Carbapenem-Resistant Enterobacteriaceae* / genetics
  • Carbapenems / pharmacology
  • Enterobacteriaceae Infections* / microbiology
  • Genetic Markers
  • Humans
  • Klebsiella pneumoniae / genetics
  • beta-Lactamases / genetics


  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Carbapenems
  • Genetic Markers
  • beta-Lactamases