Researchers are hopeful they have discovered a biomarker or biological footprint for sepsis that could form the basis of a rapid bedside blood test that returns results within 2 hours instead of the 2 days required by current diagnostics.
The team, led by King’s College London in the UK, reports the discovery in the latest online issue of the journal PLOS ONE.
Sepsis, sometimes referred to as blood poisoining, is a potentially fatal condition where the body’s immune system overreacts to an infection, which may result in septic shock. Essential organs are then disrupted, accompanied by a dangerous drop in blood pressure.
In the UK, sepsis costs the NHS over £2 billion and kills more than 37,000 people a year, which is more than breast and bowel cancer combined.
Sepsis is the leading cause of death in US hospitals, according to research that shows it affects around 750,000 patients and kills over 250,000 Americans a year.
Rapid diagnosis and treatment with antibiotics saves lives, but this is hampered by the lack of biomarkers – currently it can take up to two days to test blood samples for sepsis.
Corresponding author Graham Lord, professor and director of the National Institute for Health Research (NIHR) Biomedical Research Centre at Guy’s and St. Thomas’ NHS Foundation Trust and King’s College London, says:
“Sepsis is a hidden killer, causing nearly a third of all hospital deaths. Rapid antibiotic treatment for the condition is vital – every minute counts. Yet current diagnostic methods can take up to 2 days, so an accurate diagnostic test that can be carried out at the patient’s bedside is urgently needed.”
Prof. Lord says another important factor is that symptoms of sepsis are similar to other types of Systemic Inflammatory Response Syndrome (SIRS), but only sepsis responds to antibiotics. Giving antibiotics to patients with non-sepsis SIRS could contribute to the rising problem of antibiotic resistance.
The new biomarker is based on microRNAs, small non-coding molecules that help regulate gene expression in cells. They play a key role in disease.
For this study, the team took blood samples from three groups of people – some with sepsis, some with another type of SIRS that does not respond to antibiotics, and healthy people.
Using state of the art technology, they analyzed the samples to see which microRNAs might be disproportionately present.
They found a particular group of microRNAs in the sepsis blood samples were at a higher level than in the other samples.
To double-check the findings, the researchers replicated the results in a larger group of Swedish patients with severe sepsis.
The method they used in both studies diagnosed sepsis within 2 hours, with 86% accuracy.
Prof. Lord says:
“We have for the first time identified a group of biomarkers in the blood that are good indicators of sepsis. We have shown that it is possible to detect these markers by screening a patient’s blood in the ward, a process which can deliver results within 2 hours.”
“This is an extremely exciting development which has the potential to completely transform the management of this severe disease and save thousands of lives worldwide every year. These are promising early findings, and now we need to test this approach in a large clinical trial.”
Plans for a randomized clinical trial are already in progress at King’s College London and Guy’s and St. Thomas’ NHS Foundation Trust.
Funds for the study came from Guy’s and St. Thomas’ Charity and the NIHR Biomedical Research Centre at Guy’s and St. Thomas’ NHS Foundation Trust and King’s College London.
A company called Cepheid, which makes rapid molecular diagnostic systems, also collaborated on the study.