Duration of antibiotic therapy in Gram-negative infections with a particular focus on multidrug-resistant pathogens

Antimicrobial overuse is a major health problem that contributes to antimicrobial resistance (AMR). Infections with Gram-negative bacilli (GNB) and multidrug-resistant organisms (MDRs) are associated with high morbidity and mortality, particularly in patients with underlying medical conditions.Although many recent studies have been published about the novel antibiotics in treating infections including those due to MDR-GNB, the optimal duration of treatment (DOT) remains inconclusive. Recent observation has supported that short antibiotic therapy (SAT) decreases AMR and adverse effects. This narrative review provides an overview of the most recent published studies on the duration of therapy in the treatment of GNB infections, including hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP), intra-abdominal infections (IAIs), bloodstream infections (BSIs) and urinary tract infections (UTIs), with a particular focus on MDR-GNB.Studies showed different outcomes when comparing SAT to long antimicrobial therapy (LAT). No generalization can be made on all sites of infections and different GNBs. Further studies are needed to address the optimal DOT in MDR-GNB, as this group is underrepresented in recent studies.