Background: Multidrug-resistant (MDR) Escherichia coli is a serious threat to cancer patients. We aimed to determine the risk factors associated with the development of MDR E coli bacteremia in cancer patients and the possibility of horizontal transmission.
Methods: We conducted a 1:2 case-control study of 58 patients with MDR E coli bacteremia. The patient's demographics, clinical characteristics, and antibiotic use were obtained. MDR E coli was defined as resistant strains to quinolones plus 1 of the following: piperacillin, ceftazidime, or cefepime. Repetitive sequence-based polymerase chain reaction (Rep-PCR) was used to identify DNA interstrain similarities.
Results: Conditional multiple logistic analysis showed that admission to the hospital within the 30 days prior to infection and chemotherapy use were risk factors for infection with MDR E coli. Rep-PCR showed that, among the MDR E coli strains recovered, 48.6% showed >95% similarity, representing a possible clonal outbreak. Infection control measures were implemented and controlled this horizontal transmission.
Conclusion: Prior admission to the hospital and previous chemotherapy were independent risk factors of acquiring MDR E coli. Molecular fingerprinting techniques detected a possible nosocomial clonal outbreak of MDR E coli, which was aborted through infection control measures.