A clinician is treating a neutropenic febrile patient with suspected carbapenem-resistant Klebsiella pneumoniae (CR-KP) infection producing KPC enzyme. Which antibiotic combination represents the most evidence-based current approach for this infection?
- A Ceftazidime-avibactam alone or combined with aztreonam for MBL co-producers ✓
- B Imipenem + cilastatin at high dose
- C Colistin + tigecycline + carbapenem triple therapy
- D Meropenem + piperacillin-tazobactam
Explanation
KPC (Klebsiella pneumoniae carbapenemase) is a class A serine beta-lactamase inhibited by avibactam, a novel non-beta-lactam beta-lactamase inhibitor. Ceftazidime-avibactam is now first-line for KPC-producing CR-KP and has shown superior outcomes to the older colistin-based regimens in observational studies. Importantly, when co-infection with metallo-beta-lactamase (MBL) producing organisms is suspected, aztreonam is added because avibactam restores aztreonam's activity against MBL producers (MBLs hydrolyze carbapenems but not monobactams, and avibactam protects ceftazidime but not aztreonam from class A/C enzymes — the combination covers both). This is the key nuance in CR-KP treatment.
Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.