The prevalence of gram-negative bacteria with difficult-to-treat resistance and utilization of novel β-lactam antibiotics in the southeastern United States

Y Vivian Tsai; P Brandon Bookstaver; Joseph Kohn; Julie Ann Justo; Darrell Childress; Stefanie Stramel; Douglas Slain; Patrick Tu; Mary Joyce B Wingler; Bruce M Jones; Daniel T Anderson; Megan M Seddon; David A Cretella; Joshua Eudy; Hana Winders; Kayla Antosz; Pamela Bailey; Majdi N Al-Hasan

doi:10.1017/ash.2024.26

The prevalence of gram-negative bacteria with difficult-to-treat resistance and utilization of novel β-lactam antibiotics in the southeastern United States

Antimicrob Steward Healthc Epidemiol. 2024 Mar 18;4(1):e35. doi: 10.1017/ash.2024.26. eCollection 2024.

Authors

Y Vivian Tsai¹, P Brandon Bookstaver^{1

2}, Joseph Kohn¹, Julie Ann Justo^{1

2}, Darrell Childress³, Stefanie Stramel⁴, Douglas Slain⁵, Patrick Tu⁶, Mary Joyce B Wingler⁷, Bruce M Jones⁸, Daniel T Anderson⁹, Megan M Seddon¹⁰, David A Cretella⁷, Joshua Eudy⁹, Hana Winders¹, Kayla Antosz², Pamela Bailey^{1

11}, Majdi N Al-Hasan^{1

11}

Affiliations

¹ Prisma Health-Midlands, Columbia, SC, USA.
² Department of Clinical Pharmacy and Outcomes Sciences, University of South Carolina College of Pharmacy, Columbia, SC, USA.
³ East Alabama Medical Center, Opelika, AL, USA.
⁴ Department of Pharmacy, Memorial Hermann Memorial City Medical Center, Houston, TX, USA.
⁵ Department of Clinical Pharmacy and Section of Infectious Diseases, West Virginia University, Morgantown, WV, USA.
⁶ Department of Pharmacy, Charlie Norwood VA Medical Center, Augusta, GA, USA.
⁷ Department of Antimicrobial Stewardship, University of Mississippi Medical Center, Jackson, MS, USA.
⁸ St. Joseph's/Candler Health System, Savannah, GA, USA.
⁹ Department of Pharmacy, Augusta University Medical Center, Augusta, GA, USA.
¹⁰ Sarasota Memorial Health Care System, Sarasota, FL, USA.
¹¹ Department of Internal Medicine, University of South Carolina School of Medicine, Columbia, SC, USA.

Abstract

Objective: To evaluate temporal trends in the prevalence of gram-negative bacteria (GNB) with difficult-to-treat resistance (DTR) in the southeastern United States. Secondary objective was to examine the use of novel β-lactams for GNB with DTR by both antimicrobial use (AU) and a novel metric of adjusted AU by microbiological burden (am-AU).

Design: Retrospective, multicenter, cohort.

Setting: Ten hospitals in the southeastern United States.

Methods: GNB with DTR including Enterobacterales, Pseudomonas aeruginosa, and Acinetobacter spp. from 2015 to 2020 were tracked at each institution. Cumulative AU of novel β-lactams including ceftolozane/tazobactam, ceftazidime/avibactam, meropenem/vaborbactam, imipenem/cilastatin/relebactam, and cefiderocol in days of therapy (DOT) per 1,000 patient-days was calculated. Linear regression was utilized to examine temporal trends in the prevalence of GNB with DTR and cumulative AU of novel β-lactams.

Results: The overall prevalence of GNB with DTR was 0.85% (1,223/143,638) with numerical increase from 0.77% to 1.00% between 2015 and 2020 (P = .06). There was a statistically significant increase in DTR Enterobacterales (0.11% to 0.28%, P = .023) and DTR Acinetobacter spp. (4.2% to 18.8%, P = .002). Cumulative AU of novel β-lactams was 1.91 ± 1.95 DOT per 1,000 patient-days. When comparing cumulative mean AU and am-AU, there was an increase from 1.91 to 2.36 DOT/1,000 patient-days, with more than half of the hospitals shifting in ranking after adjustment for microbiological burden.

Conclusions: The overall prevalence of GNB with DTR and the use of novel β-lactams remain low. However, the uptrend in the use of novel β-lactams after adjusting for microbiological burden suggests a higher utilization relative to the prevalence of GNB with DTR.