Lancet Respir Med

Procalcitonin-guided triage in the ED may lower mortality but doesn’t reduce early antibiotic use

March 26, 2026

In the large multicenter PRONTO trial conducted across 20 emergency departments in England and Wales, 7,667 adults with suspected sepsis were randomized to usual care or rapid procalcitonin (PCT)‑guided care using a guidance‑only algorithm that clinicians could follow or override. Adding rapid PCT testing to standard National Early Warning Score 2 (NEWS2)‑based assessment didn’t affect early IV antibiotic initiation (48.4% with PCT vs. 48.2% with usual care at 3 hours; adjusted risk difference, –0.08 percentage points; 95% confidence interval [CI], –2.58 to 2.42; p=0.95).

However, investigators observed a notable reduction in 28‑day mortality in the PCT group (13.6% vs. 16.6%; adjusted risk difference, –3.12 percentage points; 90% CI, –4.68 to –1.57; p=0.0009), meeting both noninferiority and statistical superiority thresholds—though the mechanism for this improvement remains uncertain.

Clinical takeaway: Rapid PCT testing may reduce short‑term mortality in patients with suspected sepsis. Consider PCT as an adjunctive tool, while recognizing that further research is needed to clarify how it influences outcomes.

Source:

Todd, S et al. (2026, March 22). Lancet Respir Med. Procalcitonin testing combined with NEWS2 evaluation compared with usual care based on NEWS2 for identification of sepsis and antibiotic initiation in the emergency department in England and Wales (PRONTO): a multicentre, randomised, controlled, open-label, phase 3 trial. https://www.thelancet.com/journals/lanres/article/PIIS2213-2600(25)00433-3/fulltext