SMARTChip study
Research type
Research Study
Full title
SMARTChip: A field deployable blood test for stroke, capable of detecting brain ischaemia from the earliest stages of pathology
IRAS ID
198854
Contact name
Christopher Imray
Contact email
Sponsor organisation
University Hospitals Coventry and Warwickshire NHS Trust
Duration of Study in the UK
0 years, 9 months, 0 days
Research summary
Summary of Research
Stroke is one of the leading causes of death and disability in the UK and currently costs the country £7bn per year. There is an overwhelming need to accurately and rapidly triage patients to allow best use of finite NHS specialist resources for the treatment of stroke.We propose a simple blood test of substances (the purines) that result from cellular metabolism and are produced ub excess when brain cells are starved of oxygen and glucose (as occurs during a stroke). We have used our sensors to measure blood purines during a procedure in which blood flow to the brain is reduced to allow surgical interventions on the major arteries that supply the brain. Our studies show that as soon as blood flow to the brain is reduced, purines are produced within minutes and are detectable in systemic arterial blood.
Our project will now compare the levels of purines in the blood of stroke patients and controls. The purines will be measured on admission to hospital and 24 hours later. The occurrence and magnitude of a stroke will be determined by an MRI scan given between 24 and 72hrs after admission. This study will establish whether purines are elevated in the blood of stroke patients on admission to hospital compared to healthy controls, and whether this correlates with the size of the stroke and damage to the brain.
Summary of Results
Stroke is a devastating neural emergency that requires rapid diagnosis and treatment. For ischaemic strokes (caused by blood clots that reduce blood flow to a region of the brain) the quicker the clot can be removed, and blood flow restored, the better the final recovery for the patient. This suggests a need for new diagnostic methods that could be used at the point of injury to recognise stroke and rapidly prioritize those patients for specialised treatment.This trial set out to test whether substances known as purines, which are by products of energy metabolism in cells, could be used to detect stroke. Our underlying hypothesis was that the reduction of energy metabolism in the brain (during a stroke) generated excess purines, which enter the blood where they could, in principle, be detected via a finger prick blood test.
Prior to the trial, we had generated sensors that could measure purines in whole blood. To explore the potential utility of purines as indicators of brain ischaemia, we tested whether whole blood purines of stroke patients were elevated compared to those of healthy controls, and patients suspected of having mimicking conditions but not a stroke.
All blood measurements were taken within 4 hours of symptom onset. We found that whole blood purines were significantly elevated in stroke patients (mean ± SD: 7.6 ± 7.7 µM, n=173) compared to controls (4.2 ± 4.5 µM, n=30) and mimics (4.3 ± 3.3 µM, n=35). Whole blood purines were elevated for both haemorrhagic (7.5 ± 9.1 µM, n=30) and ischaemic (7.6 ± 7.4 µM, n=143) stroke. There was however overlap between the levels of purines in healthy controls and mimics, and those of some stroke patients. We did not find a significant correlation between volume of affected brain tissue and the measured level of whole blood purines.
Overall, purines are produced from the brain very early during the onset of stroke. More studies are required to understand how their production relates to the types of stroke and mimicking conditions, and whether they provide useful early diagnostic information that can guide critical decision making in the very earliest stages of disease progression.
REC name
West Midlands - Coventry & Warwickshire Research Ethics Committee
REC reference
16/WM/0164
Date of REC Opinion
6 Jun 2016
REC opinion
Further Information Favourable Opinion