How Do Residential Aged Care Antibiograms Compare with Other Local Resistance Data?

Background: Antibiograms can optimize empirical antibiotic prescribing; however, they are not readily available for residential aged care facilities (RACFs) in Queensland, Australia. This study aimed to determine whether alternatively available data can be used to approximate resistance patterns for RACFs.

Methods: Annual RACF-specific antibiograms were compared with local hospital antibiograms accessed through pathology providers. Additionally, composite antibiograms, of geographically united RACF data, were compared with regional hospital and private pathology RACF antibiograms. Antibiotic susceptibility rates for commonly observed bacteria (Escherichia coli, Klebsiella pneumonia, Enterococcus faecalis, Pseudomonas aeruginosa, and Staphylococcus aureus) were compared among different antibiograms using Fisher exact test, with a P value ≤ 0.05 indicating the statistically significant difference. The concordance among the antibiograms was described by percentage similarity overall and for a subset of clinically relevant pathogen-antibiotic pairs.

Results: Composite RACF antibiogram was highly concordant (83%-100% similarity) to private pathology RACF data when compared for clinically relevant pathogen-antibiotic pairs. Mixed results were found when individual RACF-specific antibiograms were compared with local hospital all-ages and ≥ 65 years data (50%-100% and 67%-100% similarity, respectively).

Conclusions: Private pathology RACF antibiograms can serve as a proxy indicator of resistance patterns for RACFs. Mixed findings were noted for comparisons with hospital data.