The following is a summary of “Natural history of carbapenemase-producing Enterobacterales: progression from carriage of various carbapenemases to bloodstream infection,” published in the March 2024 issue of Infectious Disease by Temkin, et al.

Further investigation is needed into the uncertain risk of Carbapenemase-producing Enterobacterales (CPE) progressing from residing in the body (carriage) to severe bloodstream infection (BSI) outside high-risk environments.

Researchers conducted a retrospective study investigating the rate of CPE-BSI in individuals carrying CPE, and to analyze if this rate varied based on the type of carbapenemase, bacterial species, and healthcare setting.

They conducted a nationwide population-based retrospective cohort study using national databases, including all patients in Israel with CPE detected by screening from 1/1/2020 to 10/10/2022. They determined the cumulative incidence of CPE BSI within 1 year among CPE carriers, employing a competing-risks model with BSI as the outcome and death as the competing risk.

The results showed  6,828 CPE carriers, with a cumulative incidence of CPE BSI at 2.4% (95% CI: 2.1%-2.8%). In comparison to KPC, the subhazard of BSI was lower for NDM (aSHR: 0.72, 95% CI: 0.49-1.05) and OXA-48-like (aSHR: 0.60, 95% CI: 0.32-1.12), although these disparities didn’t attain statistical significance. Compared to K. pneumoniae, the sub-hazard of BSI was diminished for carriers of carbapenemase-producing E. coli (aSHR: 0.31, 95% CI: 0.20-0.47). Additionally, the subhazard of BSI was elevated among patients with CPE carriage initially detected in intensive care units (aSHR: 2.42, 95% CI: 1.50-3.92) or oncology/hematology wards (aSHR: 3.77, 95% CI: 2.40-5.93) in comparison to medical wards.

Investigators concluded lower BSI risk in general CPE carriers than prior high-risk studies. Bacterial species and setting, not carbapenemase type, impacted BSI risk.

Source: academic.oup.com/cid/advance-article-abstract/doi/10.1093/cid/ciae110/7623571