Clinical aspects of severe infections caused by antibiotic-resistant Gram-negative bacteria

In our days, growing incidence of antibiotic resistant bacteria has become an eminent public health problem. For survival Gram-negative species possess several different tools to withstand antibiotics: they produce degrading and modifying enzymes, decrease their permeability or expel drug molecules. An increasing proportion of severe nosocomial infections are caused by strains resistant to several antimicrobials (multiresistant, extensively resistant or panresistant species). Development of new antibiotic compounds may serve as a possible solution to this problem. Ceftolozane- tazobactam is a new beta-lactam+beta-lactamase-inhibitor combination resistant to most extended spectrum beta-lactamase enzymes showing excellent anti-Pseudomonas activity. It is also effective against strains when betalactam resistance is related to porin loss or efflux pump activity. The spectrum of ceftazidime-avibactam also includes carbapenemase-(KPC)-producing Enterobacteriaceae. In addition to novel therapy, an effective infection control system together with the prudent use of antimicrobials (antimicrobial stewardship) is of paramount importance.