The Revival of Aztreonam in Combination with Avibactam against Metallo-β-Lactamase-Producing Gram-Negatives: A Systematic Review of In Vitro Studies and Clinical Cases

• Main Authors: Carola Mauri (Author), Alberto Enrico Maraolo (Author), Stefano Di Bella (Author), Francesco Luzzaro (Author), Luigi Principe (Author)
• Format: Book
• Published: MDPI AG, 2021-08-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

Infections caused by metallo-β-lactamase (MBL)-producing <i>Enterobacterales</i> and <i>Pseudomonas</i> are increasingly reported worldwide and are usually associated with high mortality rates (>30%). Neither standard therapy nor consensus for the management of these infections exist. Aztreonam, an old β-lactam antibiotic, is not hydrolyzed by MBLs. However, since many MBL-producing strains co-produce enzymes that could hydrolyze aztreonam (e.g., AmpC, ESBL), a robust β-lactamase inhibitor such as avibactam could be given as a partner drug. We performed a systematic review including 35 in vitro and 18 in vivo studies on the combination aztreonam + avibactam for infections sustained by MBL-producing Gram-negatives. In vitro data on 2209 Gram-negatives were available, showing the high antimicrobial activity of aztreonam (MIC ≤ 4 mg/L when combined with avibactam) in 80% of MBL-producing <i>Enterobacterales</i>, 85% of <i>Stenotrophomonas</i> and 6% of MBL-producing <i>Pseudomonas</i>. Clinical data were available for 94 patients: 83% of them had bloodstream infections. Clinical resolution within 30 days was reported in 80% of infected patients. Analyzing only patients with bloodstream infections (64 patients), death occurred in 19% of patients treated with aztreonam + ceftazidime/avibactam. The combination aztreonam + avibactam appears to be a promising option against MBL-producing bacteria (especially <i>Enterobacterales</i>, much less for <i>Pseudomonas</i>) while waiting for new antimicrobials.

Item Description

10.3390/antibiotics10081012
2079-6382