Trends in DTR, CR, ECR, and FQR in Four Common Gram-Negative Bacteria: A Retrospective Study from 2013 to 2021.

PURPOSE

The purpose of this study was to examine the prevalence of four important drug-resistance phenotypes: difficult-to-treat resistance (DTR), fluoroquinolone resistance (FQR), carbapenem resistance (CR), and extended-spectrum cephalosporin resistance (ECR).

METHODS

DTR was defined as insensitivity to all the β-lactams and fluoroquinolones tested. We retrospectively analyzed the distribution characteristics of specific drug-resistant phenotypes of the main Gram-negative bacteria causing bloodstream infections (BSIs) in Tongji Hospital (Wuhan, China) between 2013 and 2021: , and .

RESULTS

FQR was the main antimicrobial resistance phenotype of , accounting for 59.45% (1117/1879, 95% confidence interval, 57.21%-61.65%); the detection rates for CR and DTR were low, accounting for 1.86% (35/1879, 1.34%-2.58%), and 1.81% (34/1879, 1.30%-2.52%), respectively. However, the detection rates for CR and DTR in were 38.83% (497/1280, 36.20%-41.53%) and 35.94% (460/1280, 33.35%-38.60%), respectively. In , the detection rates of the four drug-resistant phenotypes (DTR, CR, FQR, and ECR) were all < 30%, but conversely, for , the detection rates were all > 80%. The changes in the data from 2013 to 2021 showed upward trends (z > 0) for CR-, DTR-, FQR-, CR-, DTR-, FQR-, and ECR-, but downward trends (z < 0) for ECR-, CR-, DTR-, FQR-, ECR-, CR-, DTR-, FQR-, and ECR-.

CONCLUSION

DTR warrants further attention, especially in in BSI-associated and , in which the detection rates were very high. Between 2013 and 2021 in this region, DTR- and CR- showed obvious upward trends, whereas DTR- and ECR- showed obvious downward trends.