The simple system for sensitive real-time measurement of the life threatening condition is much quicker than some existing hospital tests, which can take up to 72 hours to process.
Using a microelectrode, a biosensor device is used to detect if one of the protein biomarkers of sepsis– interleukin-6 – is present in the bloodstream. IL-6 is a molecule secreted by the immune system and the levels of it in the blood increase in many of those who have the condition.
The results of the research project show that increased levels of the molecule can be detected by the test as quickly as two and a half minutes.
The small size of the devices – microelectrodes on a needle shaped substrates – makes them ideal for initial testing and also continuous monitoring for sepsis, which is notoriously difficult to diagnose.
Dr Damion Corrigan, from the department of Biomedical Engineering at Strathclyde, said: “The research shows that the tools we’ve developed could underpin a rapid test for sepsis.
“We’ve developed a needle shaped sensor with different electrodes and have shown we can detect one sepsis biomarker in almost real time, at the clinically relevant levels.
“When levels go up, as they do in sepsis, we can detect that too. Sepsis is quite complex and difficult to diagnose but IL-6 is one of the best markers.
“Our research so far shows you can measure a single sepsis marker, but there are actually eight sensors on the needle, each about the same diameter as a human hair and the idea is that in the future we can get multiple markers on the one microchip for a more comprehensive test.”
The device takes a pin prick of blood which is then put on the chip for the result to be read. Its needle shape means it can also be implanted and used on patients in intensive care.
The research is still at an early stage and the team hopes to attract more funding to take the project forward though clinical trials, use of more markers to create a biomarker panel and commercialisation.
They believe with the right support, the test could be available for use within three to five years.
The UK Sepsis Trust estimates that around 52,000 people in the UK die every year and six million globally from the condition, yet with early diagnosis and the correct treatment, most people make a full recovery.
Sepsis develops when the chemicals the immune system releases into the bloodstream to fight an infection instead cause inflammation throughout the entire body.
Without quick treatment, it can lead to multiple organ failure and death. A delay of just one hour for giving the correct antibiotic can mean an increase in the likelihood of death.
It is usually diagnosed based on simple measurements such as body temperature, heart rate and breathing rate, with patients often giving a blood test. There is a reliance on clinical judgement and hospital laboratory techniques to diagnose the condition can take up to 72 hours to provide a result.
Researchers at the University of Leeds, Dr Chris Russell and Dr Paul Steenson, made the sensing element using microfabrication, while the Strathclyde team did all the measurements and developed the test using the sensor.
Dr Corrigan added: “At the moment the 72 hour blood test is a very labour intensive process because the doctor orders the test on a computer with samples going to a central laboratory for processing and return of the result.
“The type of test we envisage could for example be at the bedside and involve doctors or nurses being able to monitor levels of sepsis biomarkers for themselves.
“If GP surgeries had access they could also do quick tests which could potentially save lives. It could also be available in A&E departments so that anyone coming in with a question mark could be quickly ruled in or out.
“With sepsis, the timing is key. For every hour that you delay the antibiotic treatment, the likelihood of death increases.
“I would hope the test could improve survival rates by ensuring people get treatment more quickly.
“It’s not just saving lives, a lot of people who survive sepsis suffer life changing effects, including limb loss, kidney failure and post-traumatic stress disorder.
“The test could stop a lot of suffering.”
The project’s clinical advisor and co-author, Consultant Anaesthetist Dr David Alcorn, who is based at Paisley’s Royal Alexandra Hospital, said he believes the ‘extraordinary’ technology could have global implications.
He said: “Dr Corrigan and his team have produced a tiny electrode capable of detecting sepsis and at the same time diagnosing the type of infection and the recommended antibiotic, all in the space of minutes. “The implications for this are massive, and the ability to give the right antibiotic at the right time to the right patient is extraordinary.
“Finding the correct drug not only targets care for that patient, but will cut down on needless antibiotics and the reduced chance of antibiotic resistance.
“I can definitely see this having a clear use in hospitals, not only in this country, but all round the world.”
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