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A rapid pharmacogenetic test performed at the bedside for newborns being treated for sepsis may help to prevent hearing loss related to aminoglycoside antibiotics, a researcher said.

This test is designed to determine whether infants have a specific genetic variant that has been linked to deafness in babies taking aminoglycosides, reported John McDermott, MD, of the Manchester Centre for Genomic Medicine in England, presenting the at the European Society of Human Genetics conference in Milan, Italy.

He and his colleagues noted that in the U.K., there are 90,000 admissions to the neonatal intensive care unit (NICU) every year, and nearly all patients receive antibiotic therapy. In addition, the country's National Institute for Healthcare Excellence recommends a combination of a β-lactam antibiotic and gentamicin as an optimal combination to help prevent the development of antibiotic resistance. However, the specific genetic variant m.1555A>G in infants who are exposed to aminoglycoside antibiotics has been linked with sensorineural deafness.

"This study shows us the importance of rapid genetic tests to prevent severe side effects from the use of antibiotics in a small group of sepsis patients who carry a mutation in their DNA," Joris Veltman, PhD, director of the Institute of Genetic Medicine at Newcastle University in England and chair of the congress, said in a statement. "Identifying those patients within an hour can now allow doctors to prescribe alternative drugs in this group of patients, whereas the majority of patients can safely use the standard antibiotics."

The prevalence of this genetic variant in the U.K. is one in 500 (0.2%), meaning that the test could theoretically prevent up to 180 cases of deafness in Britain per year. Currently, however, hospitals rely on their core testing facilities and results can take up to 3 days to come back, McDermott noted. In contrast, the new test would take 40 minutes.

This portable point-of-care assay takes about 40 minutes at 40 cycles to get results, and the authors describe it as having sensitivity and specificity comparable to those of the validated laboratory methodology. It is also a non-invasive test, with only a buccal cell sample from the inner cheek needed. The system then extracts the DNA and genotype, the researchers explained.

"This represents the first example of a point-of-care genetic test being used in the acute setting," McDermott said in a statement. "As genomic data become ever more prevalent in the population, studies like this will be essential in establishing how patients, clinicians, and healthcare systems respond to genetic information being used to [personalize] treatment as part of everyday healthcare."

A feasibility study to introduce this test into NICUs will begin in 2018, he said.