Effect of institutional antimicrobial stewardship guidelines on prescription of critically important antimicrobials for dogs and cats.

Background: Veterinary hospital antimicrobial stewardship (AMS) guidelines might help combat antimicrobial resistance (AMR).

Objectives: Determine the conditions and types of infection for which antimicrobial drugs (AMDs) deemed critically important (CIA) by the World Health Organization (WHO) were prescribed and assess the effect of hospital AMS guidelines on adherence to International Society for Companion Animal Infectious Diseases published guidelines for the treatment of superficial bacterial folliculitis, respiratory tract disease and urinary tract infection in these cases.

Animals: Dogs and cats managed at an academic veterinary hospital from 1/21 to 6/21 and 9/21 to 6/22.

Methods: Prescriptions of cephalosporins (third or fourth generation), glycopeptides, macrolides/ketolides, polymyxins, and quinolones were identified. Data on culture and susceptibility (C/S) testing and previous AMD exposure were collected. Frequencies were compared between time periods using Fisher's exact test with Bonferroni corrections.

Results: In animals prescribed ≥1 WHO-CIA AMD, fluoroquinolones were the most frequently prescribed WHO-CIA class in dogs (567/1724, 32.9%) and cats (192/450, 42.7%). No animals were prescribed carbapenems, dihydrofolate reductase inhibitors/sulfonamides, or polymyxins. No cats were prescribed aminoglycosides or amphenicols. Institutional guidelines were followed in 57.8% (324/561) cases. The most frequent causes of nonadherence were failure to perform C/S testing 46.0% (109/237) and unnecessary use of a higher-tier AMD 43.0% (102/237). Bacterial C/S testing was more frequently performed after AMS guideline institution (59.7% vs. 46.8%, P = 0.0006).

Conclusions And Clinical Importance: Adherence to published guidelines remained poor despite an increase in C/S testing. There were no changes in the frequencies of confirmed infections, positive cultures or AMD resistance between time periods.