This electronic health record study looked at 2,752 adults with recent or past cancer in Oxfordshire, UK. Researchers examined 22 potential risk factors, including prior antibiotic exposure and age, to see how they linked to antimicrobial resistance in blood culture isolates between April 2015 and March 2025.
The analysis found that prior resistance to the same antibiotic in any culture within the last year was strongly associated with antimicrobial resistance across all pathogen-antimicrobial combinations. Specifically, patients with lymphoid or haematopoietic malignancies had higher odds of vancomycin-resistant Enterococcus bacteraemia compared to those with colorectal cancer. Younger age was also positively associated with resistance in several combinations.
The study identified these associations but did not claim they caused the infections. No safety concerns or adverse events were reported. Because this was an observational study, readers should understand that these are links between factors, not proof of direct cause. The main takeaway is that previous resistance history is a significant marker for future risk in this population.