Use of tigecycline for the treatment of prolonged bacteremia due to a multiresistant VIM-1 and SHV-12 β-lactamase–producing Klebsiella pneumoniae epidemic clone

We report the use of tigecycline, firstly with colistin and finally alone, in a patient with a persistent breakthrough bacteremia due to a Klebsiella pneumoniae isolate harboring a metallo-β-lactamase (VIM-1) and an extended-spectrum β-lactamase (SHV-12). Time-kill studies demonstrated that the combination of both compounds was synergistic along the first 12 h, suppressing the regrowth observed after 3 to 6 h when colistin was tested alone.