A simple daily blood test could help critically ill sepsis patients come off antibiotics sooner, potentially reducing drug overuse and helping tackle the growing threat of antibiotic resistance, new research shows.
The study, led by researchers at University of Manchester and Northern Care Alliance NHS Foundation Trust, and mainly funded by the National Institute for Health and Care Research (NIHR), involved 2,760 patients in 41 intensive care units across the UK and is published in the journal Anaesthesia (on 21/10/26).
They found monitoring levels of a blood marker called procalcitonin (PCT) prompted doctors to consider stopping antibiotics significantly earlier than another commonly used marker, C-reactive protein (CRP).
The ADAPT-Sepsis trial examines how doctors respond to automated advice generated from daily blood tests designed to guide decisions on when antibiotic treatment could safely end.
The new data adds to the evidence already gathered through the ADAPT-Sepsis research program. This process evaluation provides the final piece of the puzzle on whether the approach could be adopted across the NHS.
Sepsis is a life-threatening condition caused by the body's overwhelming response to infection and is responsible for thousands of deaths every year.
Patients often receive prolonged courses of powerful antibiotics because doctors are understandably cautious about stopping treatment too soon in severely ill patients.
But unnecessary antibiotic use can fuel antimicrobial resistance, increase side effects and add to healthcare costs.
The researchers found that procalcitonin-based guidance generated "stop antibiotics" recommendations nearly two days earlier than guidance based on CRP – a significant reduction.
Though doctors were more likely to follow advice generated from CRP testing, the earlier signals produced by procalcitonin offer greater potential to cut the total amount of antibiotics patients receive.
CRP testing more closely reflects existing prescribing habits and tends to recommend continuing standard care.
More than 17,000 blood samples and pieces of treatment advice were analyzed during the trial.
The most common reason doctors chose not to follow recommendations to stop antibiotics was existing microbiology guidance recommending fixed treatment durations.
Other reasons included concerns about ongoing severe illness, persistent fever and raised inflammation markers.
Principle researcher Professor Paul Dark, is Vice Dean for health and care partnerships at The University of Manchester and Professor of critical care medicine at the Northern Care Alliance NHS Foundation Trust.
He said: "For decades, intensive care doctors have faced an impossible balancing act.
“Nobody wants to stop antibiotics too early and risk a patient's life, but continuing them unnecessarily also carries real dangers for individuals and society.
“What our study shows is that simple biomarker tests can provide an additional layer of reassurance when making these difficult decisions.
“The challenge now is helping healthcare teams feel confident acting on that information so patients receive exactly the treatment they need, for exactly as long as they need it."
He added: “Blood-test-guided antibiotic stewardship could become an important tool in the fight against antimicrobial resistance if implemented alongside existing clinical guidance and prescribing frameworks.
“These findings provide new insight into how hospitals could safely reduce antibiotic exposure in some of the sickest patients in the NHS while helping preserve the effectiveness of life-saving drugs for future generations.”
NIHR-funded research like the ADAPT-Sepsis trial plays a key role in tackling the threat posed globally by antimicrobial resistance. The study team's results help to provide vital evidence for medical professionals, giving them a greater understanding of how best to treat sepsis patients and, crucially, identify when it is safe for antibiotic treatment to be halted."
Professor Rupert Pearse, Chair, NIHR-HTA Commissioning Committee
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