the INFECTIOUS DISEASES channel

🦠 IDSA 2026 AMR Gram-Negative Guidance What's New? | July 2026 🔵 ESBL-Producing Enterobacterales (ESBL-E) 🧪 New ESBL definition Ceftriaxone MIC ≥4 µg/mL 💊 New agents added ✅ Gepotidacin ✅ Pivmecillinam ✅ Oral sulopenem ✅ IV fosfomycin ✅ Cefepime-enmetazobactam (emerging role) 📌 Practice update Piperacillin-tazobactam may be considered for complicated UTI (not first choice for invasive disease). --- 🟢 AmpC-Producing Enterobacterales 🦠 New organism Hafnia alvei added as moderate-risk AmpC producer. 📌 Key updates Continue ceftriaxone if: Non-severe infection Clinical improvement Adequate source control ⚠️ Piperacillin-tazobactam appears suboptimal for invasive AmpC infections. --- 🔴 Carbapenem-Resistant Enterobacterales (CRE) ⭐ Major advance Aztreonam-avibactam introduced for NDM-producing CRE and is slightly preferred over ceftazidime-avibactam + aztreonam. 🆕 Added: IV fosfomycin Gepotidacin Pivmecillinam 🔬 Updated comparisons: Ceftazidime-avibactam vs Meropenem-vaborbactam Aztreonam-avibactam vs Cefiderocol --- 🟣 Difficult-to-Treat (DTR) Pseudomonas aeruginosa 🏆 Preferred for uncomplicated UTI Single-dose amikacin or tobramycin 🫁 Pneumonia Ceftolozane-tazobactam preferred over ceftazidime-avibactam. 💨 Nebulised antibiotics: Still not routinely recommended, but evidence is becoming more favourable. --- 🟠 Carbapenem-Resistant Acinetobacter baumannii (CRAB) 🥇 First-line therapy Sulbactam-durlobactam + carbapenem ⏳ Alternative regimens: Only as bridge therapy until sulbactam-durlobactam becomes available. If resistant: Two active non-sulbactam agents or Sulbactam-durlobactam + cefiderocol --- 🟡 Stenotrophomonas maltophilia ⭐ Preferred therapy Cefiderocol monotherapy ➕ Aztreonam-avibactam added as part of combination therapy for selected invasive infections. --- 🚨 Top 6 Take-Home Messages ✅ New FDA-approved antibiotics incorporated into guidance. ✅ Aztreonam-avibactam is now preferred for NDM-producing CRE. ✅ Sulbactam-durlobactam becomes the cornerstone of invasive CRAB treatment. ✅ Ceftolozane-tazobactam is favoured for DTR Pseudomonas pneumonia. ✅ Piperacillin-tazobactam has a limited role (acceptable for some complicated ESBL UTIs but generally not for invasive AmpC infections). ✅ Updated microbiology definitions and resistance epidemiology should guide antimicrobial stewardship and empiric therapy. > Bottom line: The 2026 IDSA guidance expands therapeutic options, emphasises newer β-lactam/β-lactamase inhibitor combinations, refines laboratory interpretation, and strengthens precision treatment based on resistance mechanisms. https://www.idsociety.org/practice-guideline/amr-guidance/