Activity of ampicillin-sulbactam, sulbactam-durlobactam, and comparators against Acinetobacter baumannii-calcoaceticus complex strains isolated from respiratory and bloodstream sources: results from ACNBio study

作者：Ecem Büyükyanbolu, Jill Argotsinger, Eric T. Beck, Robin R. Chamberland, Andrew E. Clark, Anne R Daniels, Rachael M. Liesman, Mark A. Fisher, Philip Gialanella, Jonathan Hand, Amanda Harrington, Romney M. Humphries, Holly Huse, Robert Hamilton-Seth, Julia D. Hankins, Wesley D. Kufel, Scott W. Riddell, Jamie Marino, Lars F. Westblade, A. Brian Mochon, Navaneeth Narayanan, T. Kirn, Virginia Pierce, Raghava Potula, Tsigereda Tekle, Patricia J. Simner, Robert Tibbetts, Christine Vu, Lilian M. Abbo, Octavio Martínez, Rebekah E. Dumm, David P. Nicolau, Tomefa E. Asempa, on behalf of the Acinetobacter baumannii Complex National Biorepository (ACNBio) Study Group · 发表于：Antimicrobial Agents and Chemotherapy · 年份：2025 · DOI：10.1128/aac.00379-25 · 被引用次数：9 · 研究领域：Antibiotic Resistance in Bacteria、Antibiotics Pharmacokinetics and Efficacy、Antibiotic Use and Resistance

ABSTRACT Infections caused by carbapenem-resistant Acinetobacter baumannii-calcoaceticus complex (ABC) are associated with high mortality rates and limited treatment options. This study aims to evaluate the in vitro activity of clinically utilized antimicrobials against a contemporary collection of ABC isolates with a predominant carbapenem-resistant phenotype. Geographically dispersed US medical centers ( n = 22) provided non-duplicate respiratory and bloodstream ABC isolates for surveillance testing. Antimicrobial susceptibility testing was conducted by broth microdilution and interpreted according to Clinical & Laboratory Standards Institute (CLSI) and Food and Drug Administration (FDA) breakpoints. ABC isolates ( n = 523) from respiratory tract (74.4%) and blood (25.6%) sources were recovered from patients (2023–2024). Forty percent were obtained from intensive care unit patients. Carbapenem non-susceptibility was observed in 76.9% of isolates and was more common among respiratory tract cultures. The addition of durlobactam to sulbactam decreased the MIC 90 by three-doubling dilutions from 32 to 4 µg/mL, increasing the susceptibility rate to 96.9% from 33.8%. Genome sequencing of sulbactam-durlobactam non-susceptible isolates (16/523; n = 3.1%) revealed MBL and non-enzymatic resistance mechanisms. Cefiderocol inhibited 93.5% and 76.1% of isolates at CLSI and FDA susceptible breakpoints, respectively. Minocycline susceptibility was <50%, while tigecycline and eravac...