During the mid-nineties, 95-97% of intra-abdominal infection (IAI)- associated microbes were susceptible to commonly used antibiotics. Nowadays, in Gram-negative bacilli, β-lactam resistance and the associated co-resistance to other antibiotics leading to multidrug resistance is reaching crisis proportions. This is a critical issue in the treatment of IAIs, especially for complicated IAIs and for those of nosocomial origin in severely ill patients. In this setting, this article reviews the place in the therapeutic armamentarium of ceftolozane/tazobactam, a new cephalosporin/β-lactamase inhibitor with good activity against extended spectrum β-lactamase producing Enterobacteriaceae, with stability to AmpC β-lactamases and good anti-pseudomonal activity being stable against the most common resistance mechanisms driven by mutation in Pseudomonas aeruginosa. A profound review of its in vitro activity, in vivo efficacy in animal models, pharmacodynamics, pharmacokinetics, clinical efficacy in clinical trials in complicated IAIs and safety data is performed.
Keywords: AmpC; Pseudomonas aeruginosa; ceftolozane/tazobactam; complicated intra-abdominal infections; enterobacteriaceae; extended-spectrum β-lactamases.