Hearing screening of infants in Neonatal Unit, Hospital Universiti Sains Malaysia using transient evoked otoacoustic emissions

"Association of High Risk Factors and Hearing Impairment in Infants-A Hospital Based Study"

The aim of the study was to find the association of various risk factors with permanent hearing impairment in infants. A case-control study was designed on 420 infants with permanent hearing impairment and normal hearing. The case control ratio was 1:1. Alternate sampling method was used for selecting the control group. Review of medical records and parent interview was done to collect the information of risk factors. Family history(adj. OR 7.5; 95% CI 3, 14; P = 0.000), Consanguinity (adj. OR: 4; 95% CI 2,4; P = 0.000), intra uterine infection (adj. OR 18, 95% CI: 2.3-126.5, P = 0.000), post natal infection (adj. OR 3, 95% CI: 1.3-5, P = 0.004), low Apgar score (adj.OR: 4.6, 95% CI: 1.3-15), craniofacial anomaly (OR-4.6, 95% CI: 1.4-9.5, P = 0.005) and low birth weight (adj. OR: 2.3, 95% CI: 1.2-3.8) were significantly associated with hearing impairment. Among the risk factors, intra uterine infection was having highest significant association with permanent hearing impairment. This is followed by family history, low Apgar score, craniofacial anomaly, consanguinity, post natal infection and low birth weight.

The Prevalence of Hearing Loss Among Babies in the Neonatal Intensive Care Unit in a Tertiary Hospital in Malaysia

Objective

To study the prevalence of hearing loss (HL) and to identify the possible risk factors causing HL.

Methods

This retrospective study was conducted from January 2014-December 2016 at a tertiary hospital in Malaysia. All neonates admitted to the neonatal intensive care unit (NICU), Universiti Kebangsaan Malaysia Medical Centre (UKMMC) were screened with a two-step protocol using an automated auditory brain response (AABR) and/or Otoacoustic Emission and auditory brain response (ABR). Descriptive analysis was used for the prevalence of HL, degree of HL and number of risk factors per infant.

Results

A total of 2713 babies underwent hearing screening in NICU was enrolled in this study. Two thousand six hundred eight (96%) babies passed the screening test and 214 (4%) babies required further diagnostic test. Only 105 (49%) babies completed diagnostic tests. Out of 105 babies, 40 (38.1%) babies had HL. Mild HL was the commonest HL with 22 (55%), moderate HL was in seven babies (17.5%), severe HL in two babies (5%), and profound HL in nine babies (22.5%). The presence of craniofacial anomalies was the only significant independent risk factor for HL with p<0.05 with an odds ratio of 0.105 CI 95% [0.028-0.389]. Of Babies with the presence of three or more risk factors, 100% of them had HL.There was an increased risk of hearing loss in those with craniofacial anomalies up to 11 times higher compared to those without such anomalies.

Conclusion

The prevalence of HL among the NICU babies was 1.5% and mild HL was the commonest degree of HL (55%).

Prevalence of otitis media and risk-factors for sensorineural hearing loss among infants attending Child Welfare Clinics in the Solomon Islands

OBJECTIVES

The present study aimed to assess the prevalence of otitis media and risk-factors for sensorineural hearing loss among infants in the Solomon Islands, in order to recommend an Infant Ear and Hearing Program that would be suitable to the Pacific Island context.

METHODS

Ear examinations and the JCIH Risk-Factor Questionnaire were administered to 288 infants attending Child Welfare Clinics in the Solomon Islands.

RESULTS

Overall, 150 infants (52.084%) presented with bilateral normal ear examinations and no risk-factors for SNHL. There were 73 infants (25.34%) with ear pathology in at least one ear, 13 (4.5%) of whom required referral to the ENT Clinic for medical management. The most common pathology was otitis media with effusion (OME) (21.87%). Infants aged 7-12 months were significantly more likely to present with OME (p<0.001) and a history of otitis media (p=0.017) than infants aged 0-6 months. There were 71 infants (24.65%) with at least one risk-factor for sensorineural hearing loss. The most common risk-factors were ototoxicity (8.3%), non-elective caesarean delivery (6.59%), and possible in-utero syphilis infection (5.55%).

CONCLUSIONS

The prevalence of otitis media and risk-factors for sensorineural hearing loss indicate the importance of initiating Infant Ear and Hearing Programs in the Solomon Islands. Program should facilitate early education on prevention of ear disease, as well as early diagnosis and management of children with hearing loss.

Prevalence of Hearing Impairment Among High-Risk Newborns in Ibadan, Nigeria

The burden of severe hearing impairment is increasing with two-thirds of these hearing impaired people residing in developing countries. Newborn hearing screening helps to identify early, babies who need intervention in order to prevent future disability. Neither universal nor targeted hearing screening programme is available in Nigeria. Objectives: This study was carried out to assess the prevalence of hearing impairment among high-risk newborns in UCH and the associated risk factors. Materials and Methods: Two hundred one newborns in the neonatal unit of UCH with risk factors for hearing impairment had hearing screening done using automated auditory brainstem response (AABR) at 30, 45, and 70 dB at admission and discharge, and those that failed screening at discharge were rescreened at 6 weeks post-discharge. Results: Eighty-three (41.3%) and 32 (15.9%) high-risk newborns failed at admission and discharge screening respectively, and 19 (9.5%) still failed at follow up screening. The majority of hearing loss at follow up was bilateral (94.7%) and severe (52.6%). The risk factors associated with persistent hearing loss at follow up were acute bilirubin encephalopathy (RR = 11.2, CI: 1.4-90.6), IVH (RR = 8.8, CI: 1.1-71.8), meningitis (RR = 4.8, CI: 1.01-29), recurrent apnoea (RR = 2.7, CI: 1.01-7.3), severe perinatal asphyxia NNE III (RR = 7, CI: 2.4-20.2). Conclusion: Severe and bilateral hearing impairment is a common complication among high risk newborns in UCH persisting till 6 weeks post-neonatal care. Severe perinatal asphyxia with NNE III, ABE, IVH, meningitis and administration of amikacin for more than 5 days were significant risk factors. We recommend that SCBU graduates with these risk factors should have mandatory audiologic evaluation at discharge.

Follow-up in newborn hearing screening - A systematic review

INTRODUCTION

The quality and efficiency of newborn hearing screening programs (NHS) rely heavily on appropriate follow-up. The Joint Committee on Infant Hearing recommends a follow-up rate of more than 95% of infants who fail the initial hearing screening. However, a 70% benchmark is considered to be more feasible. This high loss to follow-up (LTF) rate acts as a threat to the overall success of NHS programs. The objective of the study was to identify and examine the reported rates of LTF, attributed reasons for LTF and strategies undertaken to reduce LTF.

METHODS

Using a systematic search, articles published between 2005 to December 2015 were identified from PubMed/Medline, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Educational Resources Information Center (ERIC), Scopus, Ovid, ProQuest, and Cochrane Library. To be included in the review, the study should be exploring the loss to follow-up or drop-out rate in newborn hearing screening programs and be published in an indexed peer-reviewed journal in the English language. The main outcome measures were overall rate of LTF, factors leading to LTF and measures adopted to overcome LTF.

RESULTS

53 articles were short-listed for data extraction. Out of these, 27 were single-centre studies, 19 were multi-centre, 3 compared multiple databases, and 4 used survey-based methods. Overall LTF rates of 20% in single-centre and 21% in multiple-centre studies were observed. Educational disparity and lack of adequate knowledge among parents were associated with LTF. The most commonly used strategy to overcome LTF suggested by studies was the use of an adequate data management system.

CONCLUSION

This review is a novel attempt to explore the LTF among NHS studies, reasons for LTF and strategies to reduce LTF. This review can act as a basis for planning and execution of effective NHS programs.

The performance of distortion product otoacoustic emissions and automated auditory brainstem response in the same ear of the babies in neonatal unit

OBJECTIVE

To identify the outcomes of hearing screening using different protocols of both Distortion Product Otoacoustic Emissions (DPOAE) and Automated Auditory Brainstem Response (AABR) tests in the same ear of the babies in a neonatal unit population.

METHODS

A cross-sectional study was carried out on babies who were admitted into a neonatal unit. By using a formula of single proportion and considering 20% drop out, the number of sample required was 114. The subjects were chosen by using a systematic random sampling. The infants selected were subjected to DPOAE followed by AABR tests screening at the same setting before discharge.

RESULTS

There were 73 newborns (61.6% male and 38.4% female) participated in this study with a total of 146 ears screened. Ototoxic medication was the most common risk factor followed by hyperbilirubinaemia and low birth weight. AABR had higher passing rate (82.9%) as compared to DPOAE (77.4%). The highest passing rate was achieved if the protocol of either passed DPOAE or AABR was used (90.4%). The rate was lower when auditory neuropathy spectrum disorder (ANSD) has been considered (82.9%). Hyperbilirubinaemia, prematurity, craniofacial malformation and ototoxic drugs seem to be the high risk factors for auditory neuropathy.

CONCLUSION

AABR has a higher passing rate as compared to DPOAE. However, the use of both instruments in the screening process especially in NICU will be useful to determine the infants with ANSD who may need different approach to management. Therefore, a protocol in which newborns are tested with AABR first and then followed by DPOAE on those who fail the AABR is recommended.

Mutation detection in GJB2 gene among Malays with non-syndromic hearing loss

OBJECTIVES

To identify the mutations in the GJB2 gene and to determine its association with non-syndromic hearing loss in Malays.

METHODS

A comparative cross sectional study was conducted on a group of children from the deaf schools and the normal schools. A total of 91 buccal cell samples of non-syndromic hearing loss and 91 normal hearing children were taken. Polymerase chain reaction was used to amplify the coding region of GJB2 gene. The PCR product of GJB2 coding region was preceded with screening for mutations using denaturing high performance liquid chromatography (dHPLC) and mutations detected were confirmed by DNA sequencing.

RESULTS

Twelve sequence variations including mutations and polymorphisms were found in 32 patients and 37 control subjects. The variations were G4D, V27I, E114G, T123N, V37I and R127H in both groups, W24X, R32H, 257_259 del CGC and M34L in patients only and I203T and V153I in control subjects only. There were no association between homozygous (P=0.368) or heterozygous (P=0.164) GJB2 gene and non-syndromic hearing loss.

CONCLUSIONS

The types of GJB2 gene mutation were different and vary in Malay non-syndromic hearing loss as compared to the other races. Furthermore, the mutation did not associate with hearing loss in the population. Other related genes are believed to be involved and need to be sought in this group of patients.

Anxiety of the mothers with referred baby during Universal Newborn Hearing Screening

OBJECTIVE

To investigate the anxiety among mothers whom their babies have failed test results in the first stage of Universal Neonatal Hearing Screening Program.

PATIENTS AND METHODS

A cross-sectional study was carried out on mothers whom their baby have positive test results in the first stage of Universal Neonatal Hearing Screening Program. Face to face interview was conducted to obtain data on sociodemographic profiles, knowledge about hearing loss and past medical history. Symptoms experienced by the mothers due to positive hearing test results and level of anxiety were measured by using the Malay translation Beck Anxiety Inventory questionnaire. These mothers were then given an appointment to come for the second screening six weeks after the first screening. The same questionnaire was given to them before the start of the second screening. SPSS version 11.5 was used for data entry and analysis. Wilcoxon signed Rank Test was used to compare the level of anxiety between the first and second screening.

RESULTS

From a total of 78 mothers who were participated during the first screening, 50 of them have completed the study at the second screening (response rate=64%). Fifty-two percent of them knew about the hearing screening before hand. Ninety-six percent of the mothers became alert about their child response towards sounds after they knew that their child had failed the first hearing screening. During the first screening, 74% of the mothers felt mild anxiety which was decreased to 68% before the mothers undergone the second screening. Moderate anxiety was felt by 10% of the mothers during both the first and second screening. There were 8% of the mothers having severe anxiety during the first screening but have reduced to half (4%) before the mothers undergone the second screening. The anxiety level was significantly less before the second screening with the median score of 5 (IQR: 13.0) compared to after the first screening (8, IQR=14.25); p=0.001.

CONCLUSIONS

There are considerable portion of the mothers of false-positive test result during Universal Neonatal Hearing Screening Program experienced unacceptable anxiety. This group of mothers needs to be identified and given a necessary help.

Outcome of a newborn hearing screening program in a tertiary hospital in Malaysia: the first five years

BACKGROUND AND OBJECTIVE

Universal newborn hearing screening (UNHS) was started in the Hospital Universiti Sains Malaysia (HUSM) in January 2003. To comply with international standards, we determined the outcome of the newborn hearing screening program for the first 5 years of its implementation, from January 2003 to December 2007.

METHODS

The program screened all infants who were delivered in HUSM. In a retrospective review, the outcomes in terms of coverage, prevalence of hearing impairment, referral rate for each screening, age at detection of hearing impairment and at hearing aid-fitting were analyzed.

RESULTS

Ninety-eight percent of newborns were screened. The study included 16,100 randomly selected newborns. The initial screening referral rate was 25.5%. The prevalence of default for second and third screening was 33.9% and 40.7%, respectively. The mean (SD) age at detection of hearing impairment was 3.3 months (0.86). The mean (SD) age at fitting of a hearing aid was 13.6 (4.8) months.The prevalence of hearing impairment was 0.09%.

CONCLUSION

A newborn hearing screening program is an important tool for early diagnosis and treatment. Even though the prevalence of hearing impairment may be low, the problem needs to be addressed early as the development of infants requires normal hearing.

[Analysis of specificity and sensitivity of Polish "Universal Newborn Hearing Screening Program"]

INTRODUCTION

Polish National Universal Hearing Screening Program (PNPUHS) has got three-level structure. Audiology Outpatient Clinic in The Childrens' Memorial Health Institute in Warsaw is a center of the second and the third level. Newborns are referred to us from neonatal units, the first level in the program. We found that referred children, both with unilateral as well as bilateral referral rating in TEOAE, show a high proportion of false positive results.

AIM

To analyze a diagnostic process of healthy neonates referred to our Audiology Outpatient Clinic with referral rating in one and both ears measured by TEOAE in 2005 and 2006. Assessed parameters include: attendance of patients to further diagnostics tests, with respect to their results, specificity and sensitivity of methods: TEOAE, DPOAE, analysis of final diagnoses of hearing loss.

PATIENTS

1764 infants without risk factors of hearing loss, aged from one to six months referred with referral rating in one or both ears in TEOAE.

METHODS

Diagnostics methods include: otoscopy, DPOAE, AI, BOA. Incorrect results are indication for ABR examination, if not conclusive ASSR. Collected data were statistically analyzed by chi-squared test and Czupurow and V-Cramer coefficient.

RESULTS

998 (56,5%) of 1764 examined children passed DPOAE. Only 512 (66,8%) of remaining 766 neonates carried on further investigations. Diagnosis of hearing loss was made in 449 patients (25%), including 320 (71%) with bilateral and 129 (29%) with unilateral involvement. Sensorineural hearing loss was detected in 274 children (61%), conductive in 161 (35,8%), and mixed in 14 patients (3,1%). Global PNUHSP specificity are 95,45% and sensitivity results are 95,08% respectively. Although in our Audiology Outpatient Clinic, sensitivity rate of TEOAE and DPOAE is 94,5%, and 94,4% respectively, the specificity rate of TEOAE appeared to be 36,9% and of DPOAE 79,7%.

CONCLUSIONS

Universal newborn hearing screening program permit early diagnosis and intervention in neonates and infants before 6th month of age. High rate of specificity and sensitivity characterizes the Polish Program. Low rate of specificity detected in our outpatient clinic indicates the necessity to effect and cost analysis in neonatal units. Comparison of two groups with bilateral and unilateral referral rating in screening shows that higher number of patients follow diagnostic process from the group with bilateral incorrect results, more diagnoses of hearing loss was established in this group as well.

[Newborn hearing screening program: association between hearing loss and risk factors]

BACKGROUND

Hearing loss in newborns.

AIM

To verify the prevalence of auditory alterations in newborns of Hospital São Paulo (hospital), observing if there are any correlations with the following variables: birth weight, gestational age, relation weight/gestational age and risk factors for hearing loss.

METHOD

A retrospective analysis of the hospital records of 1696 newborns; 648 records of preterm infants and 1048 records of infants born at term. All of the infants had been submitted to an auditory evaluation consisting of: Transient Otoacoustic Emissions, investigation of the cochleal-palpebral reflexes and acoustic imittance tests, identifying the type and level of hearing loss.

RESULTS

Sensorineural hearing loss was identified in .82% of the infants who were born at term and in 3.1% of the preterm infants -- with a statistically significant difference. Conductive hearing loss was the most frequent type of hearing loss in both groups, occurring in 14.6% of the term infants and in 16.3% of the preterm infants. Alteration of the central auditory system was considered as a possible diagnosis for 5.8% of the preterm infants and for 3.3% of the term infants. For the group of infants who were born at term, a significant correlation was observed between failure in the hearing screening test and the presence of risk factors such as family history and presence of a syndrome -- the child who presented a syndrome had 37 times more chances of failing in the hearing screening test and seven times more chances of failing in the right ear when there was a family history for hearing loss. The lower the gestational age (< 30 weeks) and birth weight (< 1500 g), the higher the chances of failing in the hearing screening test (3 times more).

CONCLUSION

Hearing loss had a higher occurrence in preterm infants who remained in the ICU. Gestational age and birth weight were important variables related to the possibility of failure in the hearing screening test. A correlation was observed between the presence of a syndrome and sensorineural hearing loss in infants who were born at term.

Screening for gap junction protein beta-2 gene mutations in Malays with autosomal recessive, non-syndromic hearing loss, using denaturing high performance liquid chromatography

OBJECTIVE

To determine the frequency and type of gap junction protein beta-2 gene mutations in Malay patients with autosomal recessive, non-syndromic hearing loss.

METHODS

A total of 33 Malay patients with autosomal recessive, non-syndromic hearing loss were screened for mutations in the Cx26 coding region. Deoxyribonucleic acid was extracted from buccal swab samples and subjected to polymerase chain reaction. Slow-reannealing was performed, followed by screening using denaturing high performance liquid chromatography.

RESULTS

Eight of the samples (24.2 per cent) showed heterozygous peaks, and further sequencing of these samples revealed four patients (50.0 per cent) with the W24X mutation, two (25.0 per cent) with the V37I mutation and another two (25.0 per cent) with the G4D mutation.

CONCLUSIONS

Analysis of buccal swab samples by denaturing high performance liquid chromatography is noninvasive and suitable for rapid and reliable screening of gap junction protein beta-2 gene mutations in patients with autosomal recessive, non-syndromic hearing loss. Malay patients with autosomal recessive, non-syndromic hearing loss have different kinds of gap junction protein beta-2 gene mutations which are rarely found in other populations.

Hearing loss in Chinese school children with Down syndrome

OBJECTIVE

There is well-documented evidence in the literature concerning a high prevalence of deafness in children with Down syndrome (DS). The aim of this study was to examine the extent of hearing impairment and address the rehabilitation needs of a Chinese population with DS who were either in special schools or integrated into mainstream schools.

METHODS

This study screened 92 children with DS at their own schools and 11 were reassessed in the University of Hong Kong Hearing Centre. Hearing status of the children with DS was analyzed on the basis of their screening and reassessment results for tympanometric, transient evoked otoacoustic emission (TEOAE) and pure tone audiometric examinations.

RESULTS

A high point prevalence of hearing impairment (78% by ears or 90% by participants) in a Chinese school-aged sample of children with DS was noted. The most common degree of loss was mild to moderate. No significant gender difference, age effect or ear asymmetry was found for tympanometric failure or absence of TEOAE. An unfavorable mean speech intelligibility index score (0.2) was found for this group of children.

CONCLUSIONS

Sound field amplification and suitable acoustic modifications to classrooms were recommended for Chinese children with DS in Hong Kong to improve their listening and learning environment. The point prevalence of hearing impairment in older children with DS in this study was in contrast to a previous local study on a younger age group. Further effort is needed to determine the role of possible aging effects on the type and prevalence of hearing impairment in populations with DS.