外来急性気道感染症および急性下痢症患者における抗菌薬適正使用支援とその効果

Appropriate antimicrobial use is essential for antimicrobial resistance (AMR) improvement; therefore, antimicrobial stewardship (AS) is expected to play a crucial role in AMR. A possible inappropriate use of oral antimicrobial agents in patients with acute respiratory tract infection (ARTI) and acute diarrhea (AD) treated in an outpatient department is described in the Manual of Antimicrobial Stewardship by the government of Japan. This study evaluated the impact of AS in patients with ARTI and AD treated in an outpatient department. Oral antibiotic prescription rates, antimicrobial use density (AUD), days of therapy (DOT), bundle compliance rates, and the proportion of antimicrobial resistant bacteria from April 2011 to March 2016 (before AS) and from April 2016 to March 2021 (after AS) were assessed and compared between before AS and after AS. The numbers of eligible patients were 11,457 for ARTI (before AS: 6,610; after AS: 4,847) and 4,909 for AD (before AS: 2,945; after AS: 1,964). In patients with ARTI and AD, the oral antibiotic prescribing rates, AUD, and DOT of third-generation cephalosporins after AS were significantly lower than those before AS. In patients with ARTI, the proportion of Pseudomonas aeruginosa and Escherichia coli resistant to levofloxacin and the proportion of Streptococcus pneumoniae resistant to erythromycin after AS were also significantly decreased. In contrast, several bundle compliance rates were significantly increased. AS in the outpatient department may improve the use of antimicrobials and AMR in patients with ARTI and AD.