Surveillance data from a network of Canadian acute-care hospitals suggests that the incidence of carbapenemase-producing Enterobacterales (CPE) infection and colonization is low but increasing exponentially, according to a study published last week in Antimicrobial Resistance and Infection Control.
Using data from the Canadian Nosocomial Infection Surveillance Program (CNISP), a team led by researchers with the Public Health Agency of Canada analyzed eligible CPE isolates submitted by participating hospitals from 2010 through 2023, along with microbiologic data and data on patient characteristics and outcomes.
A previous analysis of CNISP data from 2010 through 2014 found no significant increase in incidence of CPE, which are resistant to multiple antibiotic classes, but increasing trends in CPE incidence have been reported in Canadian hospitals in recent years.
A total of 138 CPE infections were reported by 97 hospitals in 2023, for an incidence rate of 0.14 per 10,000 patient-days, up from 0.03 per 10,000 patient-days in 2010. CPE colonization incidence rose from 0.02 to 0.78 per 10,000 patient-days over the same period.
The analysis also identified rising rates of healthcare-associated (HA) CPE infections from 2019 through 2023 (0.05 to 0.09 per 10,000 patient-days), primarily from 7 hospitals that accounted for 53% of all HA-CPE infections in 2023.
Carbapenemases were most frequently detected in Escherichia coli (29%), Klebsiella pneumoniae (22%), and Enterobacter cloacae complex (16%). The most frequently identified carbapenemase families were blaKPC (46%), blaNDM (29%), and blaOXA-48 (16%).
Hospital transmission is driving the increase
The median age of patients was 67 years, and pre-existing comorbidities were common (84%). Thirty-day all-cause mortality was 19%. Most patients did not report international travel (66%) or receipt of medical care abroad (74%)—two factors that have previously been associated with CPE infection and colonization.
The study authors say the observed exponential growth is a warning that current infection-control measures in Canadian hospitals are insufficient to prevent CPE transmission.
“Our findings suggest that nosocomial transmission is driving the recent increase in CPE incidence in Canada,” they wrote. “Improved infection control measures and antimicrobial stewardship as well as access to newer antimicrobials are all urgently needed.”