Combination of aztreonam, ceftazidime–avibactam and amikacin in the treatment of VIM-1 Pseudomonas aeruginosa ST235 osteomyelitis

We describe a challenging case of patient with metallo-beta-lactamase-producing Pseudomonas aeruginosa sternal osteomyelitis following aortic valve replacement biological prosthesis. The strain exhibited multidrug-resistance phenotype carrying the blaVIM-1 gene and belonged to high-risk clone sequence type ST235. was successfully treated surgical debridement plus antibiotic therapy ceftazidime/avibactam, aztreonam, amikacin. Time-kill curves showed that this triple combination at 1 × MIC strongly synergic after 8 h, achieving 99.9% killing maintaining until 48 h.