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Sensorineural hearing loss affects one in a thousand newborn children.  Audiology teams are key to the management of these patients, with ENT surgeons, paediatricians and audiovestibular physicians playing a crucial role in the understanding of the aetiology of hearing loss.  For many years there has been little that could be done to modify the development and evolution of hearing loss, and little that could be achieved in terms of safety measures to reduce harm to hearing.   Treatments are available to allow children access to sound, and it is key that they achieve this at an early stage to allow the speech centres to fully develop while their cortical plasticity remains in the early years.  The mainstay of management is hearing amplification with hearing aids.  Treatment with conductive components of hearing loss such as glue ear, which may co-exist with sensorineural loss, with grommets can be of benefit.  For children whose loss is too great to be helped by conventional hearing aids, cochlear implants have revolutionized the management of severe to profound hearing loss.  Some families, particularly in the Deaf community, choose alternative methods of communication such as British Sign Language.   

The expansion in genetic testing has offered the route to potential future therapies.  Until recently, in NHS clinical practice only a single genetic anonmaly- GJB2- was available for testing.  The introduction of a hearing loss panel, and the expansion of genomic medicine means that there is the opportunity to test for over 140 genes in the ENT, audiovestibular or paediatric clinic without the need to refer to specialised genetic services.  This needs to be handled with great care as genetic results can create uncertainty, and can provide prognostic information about other areas of the body such as thyroid or even vision.  Recently the tantilising prospect of therapueutic intervention for hearing loss has become a possibility for a small number of genes.  Children with the OTOF (otoferlin) gene have had their hearing restored in gene therapy trials. 

But is there anything we can do to prevent hearing deteriorating in chidren who do not have pre-programmed genetic anomalies?   

Some babies contract congential cytomegalovirus (CMV).  This is a virus which can cause a wide range of anomalies in children from hearing loss to retinitis or widespread developmental issues.  In recent years, paediatric infectious disease teams have pioneered efforts to diagnose and treat cytomegalovirus infections in babies with hearing loss.  Widespread newborn hearing screening, which is now the standard of care in the UK, has opened up this possibility as hearing loss can be one of the early symptoms of congenital CMV.  In Newcastle, our protocol results in urgent urine CMV testing within 3 weeks of birth for those who are diagnosed with a permanent hearing loss.  If this is positive, babies are then treated with valgancyclovir.  This has been proven in clinical trials to reduce or prevent progression of hearing loss which is associated with CMV when started early after diagnosis.   

Premature babies are at risk of hearing loss which is associated with several factors such as jaundice, infections and hypoxia.  Many protocols for neonatal sepsis include gentamycin, which is a key life saving antibiotic.  However we know that gentamycin can be ototoxic but it has variable affects in the population.  It has been recognized that 1 in 500 patients have a gene which predisposes them to otoxicity and hearing damage.  There is a genetic test for this, but conventional laboratory tests take several days, and are not timely enough for a neonate who develops sepsis.   A new evolution in this area is point of care testing.  A rapid test is available with an analyzer in the neonatal unit which will provide an answer about gentamycin susceptibility using cheek swabs as quickly as 30 minutes.  In the patients who have this gene identified a safer antibiotic can be used which will prevent the ototoxic effects.  NICE has approved the use of the technology and evaluation is ongoing to determine if this should be the standard of care more widely. 

Management of children’s hearing by offering safer care, either through the treatment of the cytomegalovirus or avoiding ototoxic antibiotics, is becoming reality across the NHS.  It is likely that these techniques will become more widely used, offering improved hearing outcomes.