A team of specialists in the United Kingdom are investigating whether a novel hearing test could effectively detect early hearing loss in patients with cystic fibrosis (CF), a possible side effect of antibiotics used to treat recurrent disease-related chest infections.
CF is genetic disorder that mostly affects the lungs, and patients are especially vulnerable to chest infections. Usually, these infections are treated with intravenous (IV) antibiotics, the most common of which — a group of drugs called aminoglycosides — has been associated with hearing loss. The ongoing study is a collaboration between the Nottingham University Hospitals NHS Trust, The University of Nottingham and the National Institute for Health Research Nottingham Hearing Biomedical Research Unit.
“People with CF already face many challenges in managing their health to lead as full and active a life as possible. Adding hearing loss as a result of their treatment is an additional burden which they shouldn’t have to bear,” said the project’s leader, Dr. Sally Palser, in a university news release. “We are keen to find out whether this new test could act as an early warning system, enabling us to detect hearing loss in patients before they themselves have even noticed its effect. Their doctor may then be able to switch to a different medication in future to prevent any further damage from being done.”
Identifying hearing loss at an early stage
The team developed a new test, called the High Frequency Digit Triple Test (HFDT), which can be conducted during a routine CF examination. Patients using HFDT first listen through headphones to a set of three digit numbers, with variable degrees of background noise, and then are asked to insert the numbers in a keypad. The test, which is easy to use and requires no special training, is designed to pick up the alterations in higher frequency hearing that are among the first signs of damage caused by the antibiotics.
The study is now enrolling patients with CF, and expects to recruit 300 at Nottingham hospitals and two hospitals in the West Midlands — Birmingham Children’s Hospital and Heartlands Hospital. The aim is to investigate if the HFDT can identify hearing damage at an early stage, if it is appropriate for patients who are unwell and about to initiate IV antibiotics, and to determine if there are any primary genetic reasons why some patients on antibiotic treatment are more prone to hearing loss than others.
Enrolled patients will be categorized in these groups:
- Children age 11 and above, and adult patients to undergo the test alongside standard assessments as part of a regular CF clinic visit.
- Children ages 11 and over, and adult patients who are unwell and expected to initiate IV antibiotic treatment. This group will undergo both the new test and standard hearing tests prior to treatment and again at a follow-up appointment after ending treatment.
- Children ages 5-10 to help investigators assess whether HFDT is appropriate for younger patients. A control group will be recruited from schools to ascertain that CF does not affect a person’s capacity to undergo the test.
All participants taking the hearing test will be asked to provide a spit or blood sample as part of the genetic testing component of the study.
“This is a great example of clinicians and scientists in Nottingham working closely together to produce a simple but innovative diagnostic test which could make a difference to lives of children and adults with CF in Nottingham and elsewhere,” said Dr. Maria Koufali, deputy director of Research and Innovation at Nottingham University Hospitals NHS Trust. “The research could also allow us to understand why some patients are more susceptible than others to hearing loss, and help us to prevent other forms of deafness.”