Comparison of antibiotics use, urinary tract infection (UTI)-causative bacteria and their antibiotic susceptibilities among 4 hospitals with different backgrounds and regions in Japan

In this study, we compared the antibiotic use, urinary tract infection-causative bacteria and their antibiotic susceptibilities among four hospitals with different backgrounds and regions in Japan in 2014. Frequency of antibiotic use (antibiotic use density: AUD/all AUD) were: ampicillin: 0.21-20.3 (median: 1.6) and cefazolin: 0.8-34.2 (2.5), representatively. The antibiotic resistant rates of Escherichia coli were ampicillin: 1.1-52.3% (median: 51.8%), piperacillin: 47.9-49.1% (48.0%), cefazolin: 23.2-34.1% (28.9%), levofloxacin: 36.6-43.8% (40.2%).We found that there were significant correlations (1) between antibiotic resistance of E. coli and annual total amount of antibiotic use (p = 0.017), annual number of days of antibiotic use (p = 0.002) and days of therapy (DOT, p = 0.002), and (2) between antibiotic resistance of extended-spectrum β-lactamase-producing bacteria and annual number of days of antibiotic use (p = 0.004) and DOT (p = 0.004) in a rehabilitation hospital. These results suggested that more antibiotic uses could lead to antibiotic resistances. Further analyses with more number of data are being undertaken.