Variability in follow-up strategies for carbapenemase-producing Gram-negative carriers: results from an international...

Follow-up strategies to confirm loss of carriage of multidrug-resistant bacteria are needed to safely discontinue infection prevention and control measures. There are currently no evidence-based criteria to determine when a carrier of carbapenemase-producing Gram-negative bacteria (CPGN) can be considered free of carriage.

This study assessed follow-up strategies currently used for known CPGN carriers.

An online survey was launched via the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Study Group for Nosocomial Infections (ESGNI) to assess follow-up strategies for carbapenemase-producing Enterobacterales (CPE), Acinetobacter baumannii (CPAB), and Pseudomonas aeruginosa (CPPA), from October 2023 to February 2024. The survey consisted of 49 questions concerning follow-up strategies, and criteria for not screening and loss of carriage. Passive follow-up was defined as screening on occasions whereas active follow-up was prospectively planned. Descriptive analyses were performed.

One hundred and thirty-four respondents from 21 European and six non-European countries completed the survey. For CPE, more than 80% performed some kind of follow-up whereas 66.4% and 60.4% did so for CPAB and CPPA, respectively, with passive follow-up being most frequent. Passive follow-up was mostly performed when the carrier was newly admitted to hospital. Active follow-up was started within four months after first detection in 84-92%. Both consecutive negative screens and the interval from last detection were the most commonly reported criteria for confirming loss of carriage. However, there were no criteria for loss of carriage in 20-35%.

There is no consensus on the follow-up of CPGN carriers. Evidence-based strategies or consensus are urgently needed to decide when to stop preventive measures.