Findings from a systematic review and meta-analysis showed that more than 16% of patients who acquired antimicrobial-resistant bacteria, or ARB, did not have any antimicrobial exposure, researchers reported.
“Antimicrobial exposure leads to emergence and dissemination of multidrug-resistant organisms (MDROs). However, an increasing number of paleontological studies have demonstrated that antimicrobial resistance predates clinical antimicrobial use,” Erika M.C. D’Agata, MD, MPH, an infectious disease specialist in the Warren Alpert Medical School at Brown University, and colleagues wrote.
“In the more recent past, numerous longitudinal studies, which collected serial rectal or nasal samples, have shown an association between antimicrobial exposure and MDRO acquisition. However, in the great majority of these studies, a proportion of patients acquired an MDRO who were never exposed to antimicrobials from the time of enrollment to when MDRO acquisition was detected.”
D’Agata and colleagues performed a systematic review and meta-analysis of studies published between Jan. 1, 2000, and July 24, 2017, that identified antimicrobial resistance with a focus on the subset of patients not exposed to antimicrobials.
Based on results from 10 studies, they estimated that the proportion of patients who were not exposed to antimicrobials during the study period prior to acquiring an ARB was 16.6% (95% CI, 7.8%-31.8%), with a range between 0% to 57.1%. When they restricted the analysis to include ICU and non-ICU results, 6.3% and 42.7% of patients who acquired an ARB were not exposed to antimicrobials, respectively, D’Agata and colleagues reported.
“Although it is irrefutable that antimicrobial exposure leads to the emergence and spread of ARB, the results of this study demonstrate that a subset of patients can acquire ARB in the absence of antimicrobial exposure,” the authors concluded. “Further research is needed to characterize the factors contributing to MDRO acquisition among persons not exposed to antimicrobials.” – by Caitlyn Stulpin
Disclosures: D’Agata reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.