Epidemiology, aetiology and diagnosis of congenital hearing loss via hearing screening of 153 913 newborns

BACKGROUND

Congenital hearing loss (HL), one of the most common paediatric chronic conditions, significantly affects speech and language development. Its early diagnosis and medical intervention can be achieved via newborn hearing screening. However, data on the prevalence and aetiology of congenital HL in infants who fail newborn hearing screening are limited.

METHODS

The sample population included 153 913 infants who underwent newborn hearing screening, and the prevalence of congenital HL, defined as moderate to profound bilateral HL (BHL) or unilateral HL (UHL) (≥40 dB HL), in one prefecture of Japan was measured to minimize the loss-to-follow-up rate, a common factor affecting the screening procedure. Comprehensive aetiological investigation, including physiology, imaging, genetic tests, and congenital cytomegalovirus screening, was performed on children diagnosed with congenital HL.

RESULTS

The calculated prevalence of congenital HL was 1.62 per 1000 newborns (bilateral, 0.84; unilateral, 0.77). More than half of the cases with congenital bilateral or severe to profound UHL showed genetic aetiology or cochlear nerve deficiency (CND), respectively. Approximately 4% and 6% of the cases of congenital BHL and UHL were associated with congenital cytomegalovirus infection and auditory neuropathy spectrum disorder, respectively.

CONCLUSIONS

This is an epidemiological and comprehensive aetiological study of congenital HL, as determined via newborn hearing screening according to its severity and laterality, in a large-scale general population of a developed country. Our findings can serve as a reference for optimizing care and intervention options for children with HL and their families.

Non-Users and Limited Users of Cochlear Implants in Pediatric Patients: A Retrospective Cross-Sectional Study

To determine the prevalence of non-use and limited use of cochlear implants. To find out the reasons for the same. This study was carried out among the paediatric patients who underwent cochlear implantation under the SHP* scheme in Civil Hospital, Ahmedabad between 2013 and 2020.

STUDY DESIGN

Retrospective cross-sectional study.

STUDY SETTING

Civil Hospital Ahmedabad.

SAMPLE SIZE

150 paediatric patients. Patients were selected based on a random number generator. The data was collected through a telephonic interview based upon a preformed questionnaire. The study indicates that out of a total 150 participants, 109 (72.7%) used their cochlear implant regularly while 41 (27.3%) did not. Major issue faced by the participants was in the external device -damage to the device and monetary issues for its repair. The participants who have dropped the usage of their implants faced issues mostly after 2 years of usage. The age group of less than 3 years showed 15.6% of non-usage, while the age group of 3-6 years showed an increase to 34.5% of non-users. The age group of more than 6 years showed an even higher proportion (41.3%) of non-users. It is recommended that the government ensures the follow-up of the patients undergoing cochlear implantation for at least 2 years after the surgery. The proportion of non-users in the consecutive increasing age groups saw a rise in number. Therefore, it is recommended to divert the resources towards lower age groups to facilitate a better outcome.

Health-Related Quality of Life in Children With Cochlear Implants From Parents' Perspective

Background and Objectives

: To evaluate the health-related quality of life (HRQoL) in parents of children with cochlear implants and assess influencing factors. These data can enable practitioners to support patients and their families in utilizing the cochlear implant and its benefits to the fullest extent.

Subjects and Methods

: A retrospective descriptive and analytic study was conducted at the Implantation center Mohammed VI. Parents of cochlear implant patients were asked to fill out forms and answer a questionnaire. Participants included parents of children <15 years old who underwent unilateral cochlear implantation between January 2009 and December 2019, presenting with bilateral severe to profound neurosensory deafness. Participants completed the children with cochlear implantation: parent's perspective (CCIPP) HRQoL questionnaire.

Results

: The mean age of the children was 6.49±2.55 years. The mean time between implantation for each patient and this study was calculated as 4.33±2.05 years. There was a positive correlation between this variable and the following subscales: communication, well-being and happiness, and the process of implantation. For these subscales, the score was higher as the delay was greater. Parents of children who received speech therapy before implantation were more satisfied on the following subscales: communication, general functioning, well-being and happiness, implantation process, implantation effectiveness, and support for the child.

Conclusions

: The HRQoL is better in families of children who received their implant at an early age. This finding raises awareness of the importance of systemic screening in newborns.

Hearing characteristics of infantile-onset Pompe disease after early enzyme-replacement therapy

BACKGROUND

Studies suggest that enzyme-replacement therapy (ERT) is crucial to the survival of patients with infantile-onset Pompe disease (IOPD). Hearing impairment (HI) is one of the clinical sequelae observed in long-term survivors. However, the benefits of early ERT for hearing outcomes have not yet been reported. This study aimed to investigate the impact of early ERT on IOPD patients.

METHODS

This retrospective longitudinal study recruited IOPD patients who were referred by newborn screening for confirmatory diagnosis based on our rapid diagnostic criteria and received early ERT treatment between January 1, 2010, and January 31, 2018. The hearing test battery included a tympanogram, otoacoustic emission, auditory brainstem evoked response (ABR), pure-tone audiometry or conditioned play audiometry.

RESULTS

Nineteen patients with IOPD were identified, 6 of whom had hearing impairment (HI); 1 had conductive HI, 2 had sensorineural HI (one had bilateral mild HI and one had mild HI in a single ear) and 1 had moderate mixed-type HI. Two patients failed the newborn screening test and had mild HI in the ABR. The mean age of the initial time to ERT was 11.05 ± 4.31 days, and the HI rate was 31.6% (6/19).

CONCLUSION

Our study is the largest cohort to show the characteristic hearing outcomes of IOPD patients after ERT. Early ERT within 2 weeks after birth may contribute to better hearing outcomes. Clinicians should be vigilant in testing for the hearing issues associated with IOPD and should intervene early if any HI is detected.

A case report of cerebrospinal fluid leak secondary to inner ear malformation

Spontaneous cerebrospinal fluid (CSF) rhinorrhea is rare and may develop secondary to inner ear malformation. A possible diagnosis of CSF leak should be considered in any pediatric patient who presents with hearing impairment, rhinorrhea, or otorrhea. Temporal bone computed tomography should be performed in children with hearing impairments. We describe a case of congenital inner ear anomaly in a 12-month-old girl who presented with intermittent rhinorrhea after birth and detected hearing problems when she was 6 months. After diagnosis, the CSF leak was surgically repaired without complications.

Identification of a novel homozygous mutation in the MYO15A gene in a Kazakh family with non-syndromic hearing loss

BACKGROUND

Millions of people around the world are plagued by hearing loss. More than 50% of congenital or pre-lingual deafness is associated with genetic factors and has highly genetic heterogeneity. To date, although hundreds of genes have been found to be implicated in non-syndromic deafness, there are still lots of genes or loci that we need to verify.

METHODS

In this study, we performed target sequencing and Sanger sequencing in a Kazakh consanguineous family with autosomal recessive non-syndromic hearing loss. Following that, functional and structural studies predicted the pathogenic effect of novel mutations by use of the online tools.

RESULTS

We identified a novel homozygous mutation p.R3191C in MYO15A gene causing deafness in this family. The mutation p.R3191C co-segregated with the disease phenotype in this family and was not present in any public databases. Automatic tools predict that the novel mutation makes a great impact on the function and structure of MYO15A protein.

CONCLUSIONS

This is a novel mutation of MYO15A causing deafness and also the first report of MYO15A mutations causing deafness in the Kazakh families. This finding expanded the spectrum of MYO15A mutations, making it more precise for future genetic diagnosis in patients with deafness.

Implementing universal newborn hearing screening in the French Rhône-Alpes region. State of affairs in 2016 and the 1st half of 2017

INTRODUCTION

Universal newborn hearing screening (UNHS) started as public health policy in 2015 in the French Rhône-Alpes region, aiming to screen for unilateral and bilateral hearing loss. After a first and second screening (retest) in the maternity hospital, the diagnostic process occurred at a limited number of specialist centers. A deferred preliminary screening (T3) was proposed before the age of 1 month. The aims of this study were to assess implementation of the program, impact of T3, and present the incidence of hearing loss in this population.

MATERIALS AND METHODS

The retrospective observational study was based on data transmitted routinely by the 51 maternities to the regional organization responsible for newborn screening, in 2016 and first half of 2017.

RESULTS

All the facilities implemented the UNHS protocol, with 47 out of 51 using the recommended techniques. 99.7% of the 115,435 newborns were screened (excluding 0.2% of parental refusals). A retest was required for 10.2% of the babies. Among babies who didn't pass retest, 7.7% were lost to follow-up. 2.2% of the newborns were referred to diagnostic centers. The rate of T3 was 31.3% of newborns who did not pass retest. 88.6% of the infants passed T3. In the perinatal network making extensive use of T3 (75.8% versus 14.9% elsewhere), 0.6% of the infants were referred to a diagnostic center, versus 2.9% in the rest of the region (2016, p < 0.001). For 2016, the outcomes at 6 months revealed an overall hearing loss rate of 1.7‰ (4.7‰ for neonatal care unit babies), and bilateral hearing loss in 1.2‰.

CONCLUSION

In Rhône-Alpes, the national and regional objectives for UNHS were exceeded, although limiting the number of infants lost to follow-up remains essential. Repeating an automated test around 2-4 weeks after birth improves the program by decreasing the false positives of the screening. It considerably limits the number of infants referred to specialist centers, without increasing the number of patients lost to follow-up.

Frequency Of Congenital Hearing Loss In Neonates

BACKGROUND

Congenital deafness is commonest birth defect and it affects 2-4 neonates among 1000 live births. Detection and intervention especially before 6 months of age prevents severe linguistic, educational and psychosocial repercussions and helps the deaf child in the development of normal speech and language. Children who are identified after 6 months of age experience great difficulties in attaining speech and language..

METHODS

To find out the frequency of hearing loss in neonates, a hospital based observational study was conducted in Combined Military Hospital Abbottabad from June-to December 2014. One thousand new-borns selected by consecutive sampling within a specified period of time were subjected to Otoacoustic Emission (OAE) testing. Brain Evoked Response Audiometry (BERA) evaluation was performed in all those who failed OAE testing to confirm the hearing loss. Children born with microtia, meatal stenosis, cleft palate, craniofacial abnormalities and syndromic illnesses were excluded from the study.

RESULTS

Of 1000 new-borns screened, 465 were males and 535 were females whereas 632 (63.2%) were delivered through C-section and 368 (36.8%) were born via SVD. Four hundred and ninety-one (49%) babies had a positive history of consanguinity among the parents. Out of 1000 infants 13 were having hearing loss which was later on confirmed on BERA evaluation. Among them 7 were males and 6 females, 9 (69%) were born through SVD and 4 (31%) through C-section and 8 (61.5%) new-borns had a positive history of consanguinity among their parents. In all these 13 patients only 2 (15%) patients had profound while the remaining 11 (85%) had moderate to severe hearing loss.

CONCLUSIONS

Frequency of hearing loss in neonates is much higher in our study (13 per 1000) as compared to other parts of the world and demands that more studies should be undertaken on this subject to confirm this.

Evolution of Italian Universal Newborn Hearing Screening Programs

BACKGROUND

The aim of this study was to evaluate the state of implementation of the Universal Newborn Hearing Screening Programs in Italy and to determine the effect that an ad hoc legislation may have on the percentage of infants screened for detection of hearing impairment in nurseries.

MATERIAL AND METHODS

Italian Newborn Hearing Screening data were obtained during four national surveys (years 2003, 2006, 2008, and 2011). The screening rates obtained by the Regions which adopted or did not adopt a legislation to increase the newborns' coverage were compared.

RESULTS

In 2011, the average coverage rate was 78.3%, but in 12 out of 20 Regions it exceeded 95%. Coverage rate was greater in Regions that implemented an ad hoc legislation compared to Regions that did not. As a matter of fact, Regions which passed the legislation screened more than 95% of infants, whereas Regions without legislation reported a mean screening rate of nearly 67% of newborns.

CONCLUSION

Current results seem to confirm that a specific legislation might have a decisive effect on the increase of rate of coverage of newborn hearing screenings.

GJB2 mutations: Genotypic and phenotypic correlation in a cohort of 690 hearing-impaired patients, toward a new mutation?

OBJECTIVES

To analyze the clinical features of hearing impairment and to search for correlations with the genotype in patients with GJB2 mutations.

DESIGN

Case series.

SETTING

Collaborative study in referral centers, institutional practice.

PATIENTS

A total of 690 hearing-impaired patients were genotypically and phenotypically described. The mutations of GJB2 and GJB6 were studied. Heterozygous patients were searched for another mutation by microsatellite approach.

MAIN OUTCOME MEASURES

Prevalence of GJB2 mutations, microsatellite approach, hearing-impairment.

RESULTS

In 498 patients (72,17% of the cohort), no mutation was found. Homozygotous patients were 59 (8,55%), with 51 for c.35delG, 6 for p.M34T and 2 for GJB6. Compound heterozygous were 64 (9,28%) with 56 c.35delG-others mutations. Genotypes with biallelic non sense mutations had a high risk of severe to profound hearing impairment. It was frequently milder in compound heterozygotes than in c.35delG homozygotes. Heterozygous patients were 69 (10%) with 21 c.35delG, 20 p.M34T and 28 others mutations. We selected patients with a complete historical medical file (clinical and audiometric data). Then, we performed a microsatellite approach (multiplex PCR of short DNA fragments) to localize a new pathologic allele. Seventeen heterozygous patients were studied. Six patients (35%) showed the same haplotype. They were compound heterozygous bearing a new pathologic allele.

CONCLUSION

Genotype may affect deafness severity, but environmental and other genetic factors may also modulate the severity and evolution of GJB2-GJB6 deafness. A new haplotype for GJB2 is described but the exact mutation remains unknown.

A novel biallelic splice site mutation of TECTA causes moderate to severe hearing impairment in an Algerian family

Congenital deafness is certainly one of the most common monogenic diseases in humans, but it is also one of the most genetically heterogeneous, which makes molecular diagnosis challenging in most cases. Whole-exome sequencing in two out of three Algerian siblings affected by recessively-inherited, moderate to severe sensorineural deafness allowed us to identify a novel splice donor site mutation (c.5272+1G > A) in the gene encoding α-tectorin, a major component of the cochlear tectorial membrane. The mutation was present at the homozygous state in the three affected siblings, and at the heterozygous state in their unaffected, consanguineous parents. To our knowledge, this is the first reported TECTA mutation leading to the DFNB21 form of hearing impairment among Maghrebian individuals suffering from congenital hearing impairment, which further illustrates the diversity of the genes involved in congenital deafness in the Maghreb.

Neonatal Hearing Screening Programme (NHSP): At A Rural Based Tertiary Care Centre

Deafness is the most common curable childhood handicap. It is a well recognised fact that unidentified hearing impairment can adversely affect optimal speech and language development and therefore academic, social and emotional development. Universal neonatal hearing screening programmes are implemented in many developed countries. However it is still in its early stage in India. The incidence of hearing impairment in India is 1-6 per thousand newborns screened (Paediatrics 19:155-165, 1998; Indian J Paediatr 74(6):545-549, 2007; Status of Disability in India, pp 172-185 2000). To determine the incidence of permanent hearing loss of moderate to evere variety in neonates taking care in a tertiary care rural based hospital in Gujarat. It was a non randomised observational study done for duration of 3 years. All neonates born in Shri Krishna Hospital underwent screening using two stage protocols with DPOAE test and final confirmation done with BERA. Total 2534 neonates were screened out of them 52 failed and 2482 (97.94 %) neonates passed in the 1st DPOAE test with 2.05 % refer rate. Total 7 (2 per 1000) neonates were detected with hearing impairment. 10 % neonates had one or other high risk factor. Out of high risk neonates, 1.8 % were diagnosed with hearing impairment in high risk group. Overall the follow-up rate was 72.7 %. Hospital based universal hearing screening of new born before discharge is feasible at a rural based tertiary care centre. Non specialist staff is invaluable in achieving a satisfactory referral rate with two stage hearing screening protocol. However, more efficacious tracking and follow up system is needed to improve the follow up rate for diagnosis.

Identification of novel OTOF compound heterozygous mutations by targeted next-generation sequencing in a Chinese patient with auditory neuropathy spectrum disorder

OBJECTIVES

The molecular causes of auditory neuropathy spectrum disorder (ANSD) are not well known. Identification of the pathogenic mutations underlying nonsyndromic ANSD is difficult because of its extremely heterogeneous trait. The aim of the present study was to identify the genetic etiology of a single Chinese patient diagnosed with congenital ANSD by targeted next-generation sequencing.

METHODS

Targeted next-generation sequencing of 79 known deafness genes was performed in a child that was clinically diagnosed with ANSD and received cochlear implantation. Candidate pathogenic variants were confirmed by Sanger sequencing. Post-implantation outcome were evaluated in a 40 months span.

RESULTS

Novel compound heterozygous mutations p.R1583H/p.Q1883X in OTOF were identified as the pathogenic cause of the patient, correlated with a good post-implantation outcome in terms of sound detection and communication skills.

CONCLUSION

Targeted next-generation sequencing is effective for molecular diagnosis of ANSD and may provide important information for clinical management of this disease.

Cystic cochleovestibular anomaly presenting with congenital deafness and recurrent bacterial meningitis in childhood

Recurrent bacterial meningitis (RBM) in many instances is associated with identifiable anatomical defects. Presence of congenital deafness with recurrent meningitis should alert clinician for presence of middle and inner ear malformation. These defects can be demonstrated by various neuro imaging techniques and can be surgically corrected. In this case report we describe a child seen at our institute with congenital deafness and recurrent meningitis, discuss the approach to RBM and briefly describe inner ear malformation associated with the same and how to differentiate them.

A study of electrocardiographic changes in congenital deaf school children

BACKGROUND

There is evidence of cardiac abnormalities in congenital deaf school children, together called as Jervel Lange Nielsen syndrome or Long QT syndrome.

AIM

The main aim was to study the electrocardiographic changes in congenital deaf children.

MATERIALS AND METHODS

Fifty congenital deaf children aged 6-18 years were selected. ECG was taken in lead II, at rest and after exercise, as some are known to exhibit the abnormality after exercise. The child was made to run on the Tread mill till exhaustion. Corrected QT interval (QTc) was Calculated by Bazett's formula QTc = QT/ √R-R. ECG was also analyzed for other abnormalities like Twave changes, ST depression, rhythm abnormalities etc.

RESULTS

Out of 50, 2 children showed resting QTc of 0.45 sec which is diagnostically high. Mean value of QTc in deaf children(Cases) before exercise was 0.4111 ± 0.0271 sec and in controls 0.379 ± 0.020 sec. Mean value of QTc after exercise in deaf(cases) was 0.403 ± 0.028 sec and in controls 0.376 ± 0.021 sec. Eight deaf children showed ST depression and 2 biphasic T and 2 notched T waves. Thirty-three deaf children's parents had consanguineous marriage.

CONCLUSION

The results were explained on the basis of ion channellopathy in heart and inner ear which predisposes to sensorineural hearing loss and cardiac abnormality.