The rising problem of antimicrobial resistance in the intensive care unit

Mainly due to its extremely vulnerable population of critically ill patients, and the high use of (invasive) procedures, the intensive care unit (ICU) is the epicenter of infections. These infections are associated with an important rise in morbidity, mortality, and healthcare costs. The additional problem of multidrug-resistant pathogens boosts the adverse impact of infections in ICUs. Several factors influence the rapid spread of multidrug-resistant pathogens in the ICU, e.g., new mutations, selection of resistant strains, and suboptimal infection control. Among gram-positive organisms, the most important resistant microorganisms in the ICU are currently methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci. In gram-negative bacteria, the resistance is mainly due to the rapid increase of extended-spectrum Beta-lactamases (ESBLs) in Klebsiella pneumonia, Escherichia coli, and Proteus species and high level third-generation cephalosporin Beta-lactamase resistance among Enterobacter spp. and Citrobacter spp., and multidrug resistance in Pseudomonas aeruginosa and Acinetobacter species. To conclude, additional efforts are needed in the future to slow down the emergence of antimicrobial resistance. Constant evaluation of current practice on basis of trends in MDR and antibiotic consumption patterns is essential to make progress in this problematic matter.