Antibiotics
In Vitro Activity of Aztreonam-Avibactam, Cefiderocol, and Conventional Antimicrobials Against Metallo-β-Lactamase-Producing Gram-Negative Urinary Isolates: A Systematic Review and Local Single-Center Retrospective Evaluation in a Tertiary Care Hospital (2016-2025) and Evaluation of Novel Agents (2021-2025)
By Requena-Fernández L, Camacho-Blanco N, Rosales-Castillo A and 2 others.
Abstract
Background
Metallo-β-lactamase (MBL)-producing Gram-negative bacteria represent one of the greatest therapeutic challenges in contemporary clinical microbiology because of their extensive antimicrobial resistance and the limited availability of effective treatment options. Aztreonam-avibactam and cefiderocol have emerged as promising therapeutic alternatives; however, comparative evidence from routine clinical practice remains limited.
Methods
A systematic literature search was conducted in PubMed to identify studies published between 2015 and 2025 evaluating the in vitro activity of aztreonam-avibactam and cefiderocol against MBL-producing Gram-negative bacteria. A total of 22 fully accessible studies meeting the eligibility criteria were included and analyzed in the systematic review. In parallel, a retrospective cross-sectional study was performed including all urinary isolates producing MBL recovered at the Microbiology Laboratory of Virgen de las Nieves University Hospital (Granada, Spain) between January 2016 and December 2025. Antimicrobial susceptibility profiles for both novel agents and conventional antibiotics were analyzed.