Mrs Kate Johnston, Mr Phil Lindsey, Mrs Charlotte Wilson Dr Marieke Emonts, Mrs Ailsa Pickering. Newcastle upon Tyne Hospitals NHS Foundation Trust

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1 'Testing for congenital cytomegalovirus (CMV) in babies identified with permanent childhood hearing impairment (PCHI) through the newborn hearing screening programme (NHSP) Mrs Kate Johnston, Mr Phil Lindsey, Mrs Charlotte Wilson Dr Marieke Emonts, Mrs Ailsa Pickering Newcastle upon Tyne Hospitals NHS Foundation Trust

2 What is Cytomegalovirus (CMV)? (CMV) is a common virus that belongs to the herpes family of viruses. Approximately 7/1000 will be born with CMV 0.7% globally, % in the UK. Approximately 13% (1/1000) of these will be born with hearing loss or learning disability (1)(2). But other figures suggest 3 to 5/1000. CMV infection is responsible for around 25% of cases of hearing loss during childhood and is the most common non-genetic cause of SNHL. The hearing loss may be present at birth (congenital ccmv)or may develop during early childhood - varies in degree and can be unilateral or bilateral. Can be progressive. Over half of all SNHL caused by congenital CMV occurs in babies showing no symptoms at birth. (1) Dollard SC et al. New estimates of the prevalence of neurologoical and sensory sequelae and mortality associated with congenital CMV. Re. med. Virol : (2) (2) Grosse et al. Congenital CMV as a cause of permanent bilateral HL a quantitative assessment. Clin. Virol :57-62

3 Anti-viral medication Recent evidence supports the use of oral anti-viral medication (Vangancyclovir), started before 4 weeks of life for CMV infection Aim: to minimise further replication of the virus and minimise its impact, including for hearing and neural development. Congenital CMV is diagnosed by CMV shedding in the urine or saliva within the first 3 weeks of life. (3) Previously Gancylclovir was the only known effective medication but had to be taken intravenously and involved baby being inpatient for several weeks so not easily acceptable for parents. (3) CASG112: randomised placebo controlled blinded investigation of 6 weeks vs 6 months of oral vangancyclovir therapy in infants withsymptomatic congenital CMV

4 Previous work in Newcastle linking screening for congenital CMV with the newborn hearing screen (Dr Eleri Williams) BEST study Newcastle and SW London Newborn screen referrals used to identify group more likely to have congenital CMV Because onset of hearing loss can occur after the neonatal period only about half of the cases would potentially be identified through the newborn hearing screening programme Saliva or urine sample taken to test for CMV newborns in one year, 351 referrals, 248 asked about taking part, 152 agreed, 5 positive for congenital CMV and given antiviral medication?roll out

5 Should there be antenatal universal screening for congenital CMV? National Screening Committee (NSC) review evidence every few years last review Nov 2011 Universal antenatal screening cannot identify which pregnancies would result in a congenital infection with serious sequelae. No interventions available to reduce the risk of transmission from mother to child, or the development of adverse outcomes in congenitally infected infants. No treatment available for use in pregnancy Antenatal screening could lead to unnecessary abortion of many normally developing foetuses

6 Should there be postnatal universal screening for congenital CMV? Dried blood spot test known to be not very sensitive (?50%).- Could improve in future with refined DNA extraction methods etc. Saliva or urine sample test can reach high sensitivity For those infants with no symptoms at birth cannot predict which ones will develop SNHL or other adverse outcomes Risk of causing anxiety in a large number of parents whose children will turn out to have no adverse sequelae Current recommendation by NSC is against universal screening for congenital CMV but is under review

7 Previous pathway based on national NHSP guidance Referral from NHSP <4 weeks Diagnostic Assessment Permanent hearing loss suspected at the first diagnostic appointment was confirmed at a second follow up appointment, usually within a further two weeks. NHSP guidance is that PCHI should only be confirmed at corrected age 1 month to allow for any maturation

8 Modified pathway in North of Tyne to allow for congenital CMV testing Referral from NHSP <3 weeks Diagnostic Assessment The initial appointment is taken as diagnostic for sensorineural hearing loss sufficient to trigger CMV screen (with proviso that parents are told there will be a follow up assessment at corrected age 1 month and part of the reason for this is allowing for maturation) ABR/OAE and high frequency tympanometry should give consistent picture to avoid error

9 How was this achieved? Liaison and discussion between Audiology and Paediatric Infectious Diseases Consultant and ENT Audiology experience is that SNHL detected within the first couple of weeks after birth actually does not change by corrected age 1 month and therefore it is appropriate to trigger the CMV screen after the first test session Audiology request the CMV screen direct rather than through ENT which would likely cause delays (timing is critical) Audiology and newborn hearing screeners keep close eye on the online booking diary to try and ensure appointments within 2/3 after birth for well babies

10 The process (1) Diagnostic assessment OAE High frequency tympanometry Auditory Brainstem response (tone pip and bone conduction)

11 The process (2) Baby <=3 weeks old, testing at initial appointment suggests sensorineural hearing loss of any degree, bilateral or unilateral Discuss results with parents. Explain the hearing loss and that there will be a further test at corrected age 1 month but this is unlikely to change the picture. Explain about CMV as being one possible cause that can be looked into. Offer CMV screen. If verbal consent obtained liaise with infectious diseases team either for testing on the day (especially for families that have travelled substantial distance to Newcastle) or team contacts family by phone to arrange test with next couple of days. Provide urine pad for putting in nappy prior to CMV test appointment Issue how much information for Audiology to give parents about CMV?

12 The process (3) Urine sample taken by paediatric infectious diseases nurse (ideally baby arrives at their appointment with a wet pad) Detailed questions about ccmv answered Results to parents within two days Positive for ccmv offer and start antiviral medication. Negative for ccmv no further action. ccmv result is known by the time child attends Audiology for their second diagnostic hearing assessment

13 Results from Newcastle Service over a two year period Babies referred for ccmv screening ( ) ccmv positive ccmv negative 31% 69% 34 babies diagnosed with permanent hearing loss 5/16 babies tested for ccmv in 2 year period = 31% 18% of all babies with PCHI (6 out of 34)

14 Reasons for not being referred for ccmv screening Declined Conductives NICU Delay at screening Delay at assessment 17 babies were not referred (2 declined Deaf families, 9 NICU, 2 permanent conductive, 2 seen late for assessment due to cancelled appts, 2 seen late due to delay at screening)

15 Summary - The incidence of CMV causing hearing loss at birth for our service is similar to previously reported. - It is reported elsewhere that 25% of asymptomatic babies with CMV will develop hearing loss by age 4 (numbers are small but our figures suggest this is higher than previously thought neonatally) - In Newcastle 16 babies with known SNHL have been referred for CMV screening at <3 weeks age over a two year period. 5 of these babies (31%) were identified as CMV positive. - Finding babies that can start treatment for CMV at 4 weeks adds value to NHSP and could potentially prevent further deterioration of hearing loss as well as other neurological sequelae. This model could be successfully applied elsewhere.

16 CASG403 Current multi-centre study for older children with hearing loss due to congenital CMV 6 weeks of oral Vangancyclovir therapy in infants with congenital CMV and hearing loss aged 1 month to 3 years Aim to assess the effectiveness of starting antiviral treatment in young children after the first month of life, when the great majority are diagnosed 17 sites in UK/USA looking for 54 recruits to make significant findings Aim to recruit 2-3 children in Newcastle Assess hearing at baseline, children get 6 weeks VGCV or placebo, repeat test 6 months after baseline