Risk factors for isolation of carbapenem-resistant Enterobacterales from normally sterile sites and urine

Invasive infections caused by carbapenem-resistant Enterobacterales (CRE) are of significant concern in health care settings. We assessed risk factors for a positive CRE culture from a sterile site (invasive infection) compared to isolation from urine in a large patient cohort in Atlanta from August 2011 to December 2015.

CRE cases required isolation, from urine or a normally-sterile site, of E. coli, Klebsiella spp., or Enterobacter spp. that were carbapenem-nonsusceptible (excluding ertapenem) and resistant to all third-generation cephalosporins tested. Risk factors were compared between patients with invasive and urinary infections using multivariable logistic regression.

A total of 576 patients had at least 1 incident case of CRE, with 91 (16%) having an invasive infection. In multivariable analysis, the presence of a central venous catheter (OR 3.58; 95% CI: 2.06-6.23) or other indwelling device (OR 2.34; 95% CI: 1.35-4.06), and recent surgery within the last year (OR 1.81; 95% CI: 1.08-3.05) were associated with invasive infection when compared to urinary infection.

Health care exposures and devices were associated with invasive infections in patients with CRE, suggesting that targeting indwelling catheters, including preventing unwarranted insertion or encouraging rapid removal, may be a potential infection control intervention.

Future infection prevention efforts to decrease CRE cases in health care settings should focus on minimizing unnecessary devices.