A simple cheek swab could save babies from permanent and profound deafness in the world’s first emergency genetic bedside test, which is being trialled on the NHS.
The swab means that nurses can identify whether a premature baby would be genetically predisposed to being left deaf after treatment with gentamicin, a life-saving antibiotic used to treat 90,000 newborns a year. Guidelines say a baby should have gentamicin administered within an hour, though researchers have known for 25 years that the antibiotic could lead to deafness caused by a genetic variant which affects 1 in 500 people. Testing for it has traditionally taken days.
But now, in just 20 minutes a nurse working alone can establish, by placing cells from a baby’s cheek swab into a into a PC-sized molecular-diagnostic bedside machine, whether their infant patient has the genetic variant which rules out using gentamicin – and if so to prescribe an alternative drug instead.
The test, which already has Health Research Authority, CE and ethical approval, has just started trials in neonatal intensive care units at St Mary’s Hospital, Manchester, part of Manchester University NHS Foundation Trust, and Liverpool Women’s Hospital. Used across the NHS, it could save more than 180 babies a year from going deaf as a result of gentamicin.
Bill Newman, professor of Translational Genomic Medicine at the University of Manchester and consultant at Manchester University NHS Foundation Trust, who is leading the trial, says that the technology could be used in future to identify how patients are affected by other drugs.
Mr Newman – whose team includes the developers of the testing equipment genedrive plc and parents of children treated in NICUs – said: “Successful implementation of the gentamicin test will be a first in the integration of a rapid decision-making, genetic-based diagnostic in the UK NHS. It opens the door to getting much better outcomes for a number of other diseases too now that the test is out there.”
In addition to saving families from the emotional anguish of a diagnosis of profound deafness, the success of the Pharmacogenetics to Avoid Loss of Hearing (PALoH) study will save the NHS an estimated £5m every year (including the cost of the test) in cochlear implantations and other hospital costs, according to health economists making up part of the team.
The Genedrive test costs around £60 per baby at the moment and was developed by the Manchester-based medical equipment company genedrive plc, in collaboration with Mr Newman’s team. The development research took place at Manchester Biomedical Research Centre with £900,000 in funding from the National Institute for Health Research (NIHR) and support from the charity Action on Hearing Loss.
Mr Newman is convinced that the successful implementation of this trial will open the door to early detection of more common conditions. His team is already working with genedrive plc on a similar rapid bedside test for stroke patients – to detect the one in 10 patients whose DNA makes them unable to metabolise clopidogrel, the common anti-platelet medication, and therefore have significantly worse outcomes.
Models suggest similar tests could prevent several thousand of the 100,000 strokes suffered by people each year in the UK. It also opens up the possibility of using pharmacogenetics testing more widely by using biomarkers to target treatments more appropriately. Mr Newman said: “It raises the long term possibility of developing a series of tests which might be given to everyone at the age of maybe 40 or 50 (when people start to develop health problems) to look at various genes that we know to be linked to specific drug outcomes. Health passports linked to electronic patient records might then be developed that contain information such as ‘codeine does not work for this patient’.”