Emerging resistant Gram-negative aerobic bacilli in hospital-acquired infections.

The increasing emergence of serious multidrug-resistant (MDR) Gram-negative infections has led to a new health-care crisis. These infections predominately include MDR Pseudomonas aeruginosa, extended-spectrum beta-lactamase-producing Enterobacteriaceae and MDR Acinetobacter baumannii. These organisms are present in a variety of clinical settings, but there is a distinct paucity of antibiotics to effectively treat these infections. The increasing use of broad-spectrum antibiotics and lack of good stewardship have contributed to the increase in these MDR organisms. This review focuses on the main MDR Gram-negative infections contributing to the current crisis in health care, their mechanisms of resistance and various treatment options for empiric therapy.