Introduction: Studies have shown many genes influence antibiotic resistance, and the relationship between genotypic and phenotypic antibiotic resistance is unclear. We sought to analyze the concordance between the presence of antibiotic resistance (ABR) genes and antibiotic susceptibility results. Methods: Urine samples were collected from patients presenting with possible UTI to 37 Urology clinics from July 2018 to February 2019. Multiplex polymerase chain reaction (M-PCR) was used to test for 33 ABR genes. Pooled Antibiotic Susceptibility Testing (P-AST) was performed against 14 different antibiotics. The concordance rate between the ABR genes and P-AST results was generated. The concordance rates for each antibiotic between monomicrobial and polymicrobial infection were compared using chi-square analysis. Results: Urine samples were collected from 2,512 patients. Bacteria were detected in 1,579 (63%). ABR gene genotyping and P-AST analysis was performed for 1,155. ABR genes were detected in 36.3% (419/1155) of specimens. Overall, the presence or absence of ABR genes was 60% concordant with antibiotic susceptibility patterns. Discordant rate was 40%. Table 1. Concordance rates were significantly lower for polymicrobial infections for vancomycin, meropenem, and piperacillin/tazobactam (p<0.05). Conclusion: The concordance rate of the ABR genes and phenotypic resistance was 60%. In 40%, the reliance on ABR report without the phenotypic sensitivity may lead to inappropriate treatment.
Vollstedt A, Wang D, Luke N, Baunoch D, Wojno K, Korman H, Gaines N, et al. Concordance between antibiotic resistance genes by multiplex polymerase chain reaction and antibiotic susceptability by pooled antibiotic sensitivity testing in symptomatic patients with urinary tract infection. Paper presented at: The 95th Annual Meeting of the North Central Section of the AUA; 2021 Oct 6-9; Chicago, IL. Available from: https://ncsaua.org/docs/meetings/ncs2110/ncs-2021-program-book.aspx