Unnecessary Use of Antimicrobials in Hospitalized Patients

TLDR

Unnecessary antimicrobial use promotes antimicrobial‑resistant nosocomial pathogens by eradicating normal anaerobic flora that suppress pathogenic overgrowth. A prospective observational study at a 650‑bed university hospital monitored adult non‑ICU inpatients prescribed new antimicrobials over a two‑week period to assess the frequency, reasons, and patterns of unnecessary use. Of 1941 antimicrobial days for 129 patients, 576 (30%) were unnecessary, mainly due to prolonged therapy, treatment of non‑infectious or colonizing organisms, and antianaerobic agents accounted for 203 (35%) of these days despite available alternatives.

Abstract

<h3>Background</h3> Unnecessary use of antimicrobials contributes to the emergence and dissemination of antimicrobial-resistant nosocomial pathogens in part through elimination of normal anaerobic bacterial flora that inhibit overgrowth of pathogenic microorganisms. <h3>Methods</h3> A prospective observational study was conducted in a 650-bed, university-affiliated hospital. All adult nonintensive care inpatients for whom new antimicrobials were prescribed during a 2-week period were monitored throughout their hospitalization. We examined how often antimicrobials, in particular those with antianaerobic activity, were used unnecessarily. The reasons for unnecessary therapy were assessed and common patterns of unnecessary use were identified. <h3>Results</h3> A total of 1941 antimicrobial days of therapy were prescribed for 129 patients. A total of 576 (30%) of the 1941 days of therapy were deemed unnecessary. The most common reasons for unnecessary therapy included administration of antimicrobials for longer than recommended durations (192 days of therapy), administration of antimicrobials for noninfectious or nonbacterial syndromes (187 days of therapy), and treatment of colonizing or contaminating microorganisms (94 days of therapy). Antianaerobic agents accounted for 203 (35%) of the 576 unnecessary antimicrobial days of therapy, and these agents were also frequently prescribed (98 days of therapy) when equally efficacious alternative regimens with minimal antianaerobic activity were available. <h3>Conclusions</h3> In our institution, hospitalized patients frequently received unnecessary antimicrobial therapy, and antianaerobic agents were often prescribed when this spectrum of activity was not indicated.