Survival trends in patients with difficult-to-treat, antibiotic-resistant, Gram-negative infections in the era of next-generation antibiotics in the USA: a retrospective cohort study

Difficult-to-treat resistant (DTR) Gram-negative infections—resistant to most first-line antibiotics—are associated with high mortality. This large US study (2016–2023) assessed whether newer antibiotics have improved outcomes.

Although the use and availability of newer antibiotics increased over time, most patients still received initial treatments that were ineffective against the infecting bacteria. As a result, overall mortality rates did not improve for most infections, despite the introduction of these newer drugs. Only a small decline in mortality was observed for Pseudomonas aeruginosa bloodstream infections.

The main problem is not just access to new antibiotics, but delayed or inappropriate initial treatment. Faster and more accurate diagnosis of resistant infections is critical to improving survival.