Antibiotic Resistance of Escherichia coli in Human Populations in Response to Decreased Cephalosporin Consumption: A Systematic Review

Widespread use of antibiotics has led to the spread of antibiotic-resistant infections in human populations, with multi-drug resistant bacteria causing over 2 million illnesses and approximately 23,000 deaths annually in the US. Escherichia coli is recognized as one of the most commonly antibiotic-resistant bacterial threats. This systematic literature review investigated the change in prevalence of cephalosporin-resistant E. coli in human populations in response to a decrease in cephalosporin consumption. The systematic methodology of the Navigation Guide was employed to conduct searches of the existing published literature in the PubMed and Scopus databases through 19 November 2018. Eleven studies consisting of original research met inclusion criteria and were evaluated individually for risk of bias. Quality and strength of overall evidence across all studies was assessed. All studies included looked at antibiotic resistance within hospital systems and among patients with a wide range of acute medical conditions, including some with severe illnesses. Among these eleven studies, six found a decrease in prevalence of cephalosporin-resistant E. coli following a reduction in cephalosporin use, two studies saw an increase in resistance, and three found no change. Studies that found a decrease in cephalosporin resistance were mostly from China or Southeast Asia, whereas the two studies that found an increase in resistance were from Spain and Germany. There were no studies that met inclusion criteria from North America, South America, or Africa. Among the included studies, the largest risk of high or probably high risk of bias was due to confounding (64%) and recruitment strategy (55%). Overall, there was a generally consistent outcome in decreased cephalosporin resistance in E. coli in response to decreasing cephalosporin consumption. Studies supporting this were conducted in settings where more strict controls on antibiotic prescription could be implemented, such as in China, where government-control of the medical system may be able to exert more control over antibiotic use. Due to risk of bias in some studies because of issues with study design, there is a need for more robust research in this area with stronger study designs. Additionally, further research conducted in community-dwelling populations and those with less severe community-acquired illnesses is needed to better answer our research question. There is also a need for research in other geographic locations, particularly in the Western Hemisphere. Future systematic reviews on antibiotic use and antibiotic resistance for other organisms and antibiotics would also be highly informative