Antimicrobial Resistance among and Therapeutic Options against Gram-Negative Pathogens

Gram-negative bacterial pathogens are a common cause of infection, and the prevalence and rates of resistance among these pathogens to existing antimicrobial agents are increasing. beta-Lactamase-mediated resistance is of particular concern. High-level resistance attributable to beta-lactamase expression alone or in combination with other mechanisms is becoming increasingly prevalent among Enterobacteriaceae and gram-negative nonfermenting organisms. Doripenem is a new carbapenem with strong coverage of difficult-to-treat gram-negative bacterial pathogens. Its activity against Pseudomonas aeruginosa exceeds that of other carbapenems, and it has equivalent activity against Acinetobacter species and most Enterobacteriaceae. Thus, doripenem may be valuable alone or in combination with other agents in the treatment of serious gram-negative infections.