Risk factors for sensorineural hearing loss in NICU infants compared to normal hearing NICU controls

UK and US risk factors for hearing loss in neonatal intensive care unit infants

IMPORTANCE

Early detection and intervention of hearing loss may mitigate negative effects on children's development. Children who were admitted to the neonatal intensive care unit (NICU) as babies are particularly susceptible to hearing loss and risk factors are vital for surveillance.

DESIGN, SETTING AND PARTICIPANTS

This single-centre retrospective cohort study included data from 142 inborn infants who had been admitted to the NICU in a tertiary regional referral centre. Data were recorded for 71 infants with confirmed permanent congenital hearing loss hearing loss. To determine impact of NICU admission independently of prematurity, babies were individually matched with 71 inborn infants on gestational age, birthweight, and sex.

MAIN OUTCOMES AND MEASURES

Neonatal indicators were recorded for all children with permanent congenital hearing loss. Presence of UK and US risk factors for hearing loss were collected on the neonatal population with hearing loss and for the matched controls.

RESULTS

A fifth (21%) of babies with hearing loss had one or more UK risk factors whereas most (86%) had at least one US risk factor. False positives would be evident if US factors were used whereas the matched controls had no UK risk factors. Ten babies who at birth had no UK or US risk factors did not have any significant neonatal indicators identified in their records, one was ventilated for one day and two had a genetic anomaly.

CONCLUSIONS AND RELEVANCE

Current risk factors for hearing loss we identified for follow-up in this high-risk group are highly specific for congenital hearing loss. UK risk factors were highly specific for hearing loss but not sensitive and conversely, US risk factors are sensitive but not specific so false positives would be recorded. A national study of neonatal indicators could provide the utility to test which combinations of risk factors provide high sensitivity without losing specificity.

Hearing impairment after asphyxia and neonatal encephalopathy: a Norwegian population-based study

The purpose of this study is to evaluate the association between perinatal asphyxia, neonatal encephalopathy, and childhood hearing impairment. This is a population-based study including all Norwegian infants born ≥ 36 weeks gestation between 1999 and 2014 and alive at 2 years (n = 866,232). Data was linked from five national health registries with follow-up through 2019. Perinatal asphyxia was defined as need for neonatal intensive care unit (NICU) admission and an Apgar 5-min score of 4-6 (moderate) or 0-3 (severe). We coined infants with seizures and an Apgar 5-min score < 7 as neonatal encephalopathy with seizures. Infants who received therapeutic hypothermia were considered to have moderate-severe hypoxic-ischemic encephalopathy (HIE). The reference group for comparisons were non-admitted infants with Apgar 5-min score ≥ 7. We used logistic regression models and present data as adjusted odds ratios (aORs) with 95% confidence intervals (CI). The aOR for hearing impairment was increased in all infants admitted to NICU: moderate asphyxia aOR 2.2 (95% CI 1.7-2.9), severe asphyxia aOR 5.2 (95% CI 3.6-7.5), neonatal encephalopathy with seizures aOR 7.0 (95% CI 2.6-19.0), and moderate-severe HIE aOR 10.7 (95% CI 5.3-22.0). However, non-admitted infants with Apgar 5-min scores < 7 did not have increased OR of hearing impairment. The aOR for hearing impairment for individual Apgar 5-min scores in NICU infants increased with decreasing Apgar scores and was 13.6 (95% CI 5.9-31.3) when the score was 0.          Conclusions: An Apgar 5-min score < 7 in combination with NICU admission is an independent risk factor for hearing impairment. Children with moderate-severe HIE had the highest risk for hearing impairment. What is Known: • Perinatal asphyxia and neonatal encephalopathy are associated with an increased risk of hearing impairment. • The strength of the association, and how other co-morbidities affect the risk of hearing impairment, is poorly defined. What is New: • Among neonates admitted to a neonatal intensive care unit (NICU), decreased Apgar 5-min scores, and increased severity of neonatal encephalopathy, were associated with a gradual rise in risk of hearing impairment. • Neonates with an Apgar 5-min score 7, but without NICU admission, did not have an increased risk of hearing impairment.

Hearing Loss and Risk Factors in Very Low Birth Weight Infants

The incidence of sensorineural hearing loss (SNHL) is still high in very low birth weight (VLBW) infants. The purpose of our study was to provide the prevalence rates of SNHL and to analyze the risk factors of hearing impairment and changes in hearing thresholds in a cohort of VLBW infants. A retrospective observational study was conducted in our neonatal intensive care unit (NICU) from 2012 to 2016. All VLBW infants included were screened by transient evoked otoacoustic emissions (TEOAEs) and diagnostic auditory brainstem response (ABR). In total, we enrolled 316 infants and SNHL was diagnosed in 68, leading to an early incidence of 21.5% as 36 infants out of 68 improved. Finally, SNHL was confirmed in 20 patients (6.3%) who needed hearing aids. They were significantly smaller, sicker, had longer hospitalizations, and received more ototoxic therapies. Logistic regression analysis showed that gestational age (GA) influenced the association between drugs and SNHL. The results underlined how the total exposure to antibiotics is significantly associated with SNHL, even after GA correction. In conclusion, GA, birth weight and, above all, the length and complexity of NICU stay quantify the risk of SNHL and should be considered at the individual level for parent counseling.

Roles and reported practices of paediatricians in the early identification and monitoring of hearing impairment in high-risk newborns and infants

BACKGROUND

The paediatrician is often the first professional who provides care for the infant and their families, hence having a vital role in the early identification and intervention of hearing impairment.

OBJECTIVE

This study aimed to identify the role and reported practices of paediatricians in the early identification and monitoring of hearing impairment in high-risk newborns and infants.

METHODS

The sample comprised 30 paediatricians in South Africa. Data were collected by means of an online survey and analysed using descriptive statistics.

RESULTS

Variability was noted in the early identification protocols, with most participants conducting objective measures. Although most participants refer newborns and infants for audiological evaluation when hearing impairment is suspected, there is variability with regard to the age at which they are referred. Approximately 98% of participants believe that they form part of the multidisciplinary team; however, only 69% reported that they have actually been part of a multidisciplinary team.

CONCLUSIONS

Paediatricians had sufficient knowledge regarding the assessment of hearing impairment and their role in the early hearing detection and intervention programme. There is however a need for information sharing regarding appropriate hearing screening measures.

"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.

Is chorioamnionitis associated with hearing impairment in preterm infants? A systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

It has been reported that chorioamnionitis (CA) could increase the risk of hearing impairment in premature infants, but results are inconsistent. A meta-analysis was performed to systematically evaluate the relationship between CA and hearing impairment in premature infants.

MATERIAL AND METHODS

Search in PubMed, Embase, Cochrane Library from their inception to May 2020. We concluded all cohort and case-control studies which explored the associations between CA and hearing impairment in preterm infants. Pregnant women with other infections besides CA were excluded. PRISMA guidelines were followed. Fixed-and random-effects models were used, depending on heterogeneity. And we performed to calculate odds ratio (ORs), and 95% CIs using fixed-effects models.

RESULTS

Seven studies involving 4134 premature infants were included. There was non-significant association between CA and hearing impairment (adjusted OR 1.43, 95% CI 0.99 to 2.04, P = 0.05; heterogeneity: I² = 13%, P = 0.33).

CONCLUSION

This article concludes that CA is not a risk factor for hearing impairment in premature infants, but most of the current studies are retrospective studies with low intensity and lack of high-quality articles to discuss it.

Newborn Hearing Screening: Analysing the Effectiveness of Early Detection of Neonatal Hearing Loss in a Hospital in Greece

Introduction The introduction of newborn hearing screening programs (NHSP) has drastically contributed to the early diagnosis of hearing loss (HL) in children, with the prospect of children developing speech as early as possible. This retrospective study aims to present and discuss the preliminary results of the NHSP at the University Hospital of Patras, Greece, highlighting the strengths and weaknesses of the program. The evaluation of the implementation of NHSP is important to confirm the effectiveness of the process and elaborate system failures. Materials The study describes the results of previous data collected from the NHSP in the Rio hospital of Patra and analyzed the conditions of the sample collected. The random sample involved newborns born between November 2018 - December 2020 at the University Hospital in Patra, Greece, which was assessed using transient evoked otoacoustic emissions (TEOAEs). Testing was performed twice per week on Thursday and Friday with a random sample, specifically examining the babies in the hospital these days. From the 2014 newborns assessed, 1491 were healthy neonates, while the other 523 required hospitalization in the neonatal unit. Results In total, there were 2014 live births; 1491 healthy neonates were screened with TEOAEs. Of them, 44 did not pass the first test. After retesting one month later, 31 passed the test, while the other 13 were referred to a hearing centre for further audiological testing with auditory brainstem response (ABR) tests. Two infants never showed up for the follow-up appointment. Of the remaining 11, six infants had normal hearing, three had otitis media with effusion or other conductive HL. The last two infants had HL. Specifically, one had bilateral sensorineural HL greater than 40db, and one had unilateral sensorineural HL greater than 40db. Risk factors were identified in 523 newborns admitted to the unit. The most common risk factors identified were the use of ototoxic drugs, low Apgar scores, and prematurity. Of all the newborns, 491 passed the test the first time, and the rest 32 infants came back 1-2 months after leaving the neonatal unit. All the babies who had failed in the first screening test appeared for the follow-up appointment for the second screening test. Of these, 24 babies passed the test, but eight did not. Of these, four were diagnosed with media otitis with effusion or other conductive HL. Sensorineural HL was identified in the last four babies using ABR tests. In detail, two had unilateral sensorineural HL greater than 40db, while two had bilateral sensorineural HL greater than 40db. Conclusion In conclusion, we found that for the NHS programs to be effective, they must be implemented long-term and have monetary support. Early diagnosis and cochlear implantation are the keys to excellent outcomes. Cooperation between different specialties and a patient-centred approach will help physicians holistically face neonatal HL. Building trust between the parents and doctor is essential for the program's success and reducing the lost-to-follow-up rate. To run a successful program, trained staff, equipment, and financial support are required. However, the gold standards for the success of the program are proper implementation of the program, close follow-up, strict adherence to the guidelines in the neonatal intensive care unit (NICU), and the early detection and diagnosis of HL.

Retinopathy of Prematurity and Hearing Impairment in Infants Born with Very-Low-Birth-Weight: Analysis of a Korean Neonatal Network Database

Background: To investigate hearing impairment and its association with retinopathy of prematurity (ROP) among children born with very low birth weight (VLBW, birth weight < 1500 g). Methods: This prospective registry study included 7940 VLBW infants who underwent both ophthalmic (ROP) and hearing screening at the 70 participating centers of the Korean Neonatal Network. Hearing screening was performed using auditory brainstem response and/or automated otoacoustic emission testing. Hearing impairment, defined as a unilateral or bilateral hearing threshold of ≥40 dB on the auditory brainstem response threshold (ABR-T) test, was evaluated and compared between children with and without ROP at the corrected ages of 18 months and 3 years. Results: The frequency of infants who did not undergo hearing screening at near-term ages was higher in the ROP group than in the no-ROP group (18.2% vs. 12.0%, p < 0.001), and the prevalence of hearing impairment at 18 months was higher in the ROP group than in the no-ROP group (3.5% vs. 2.2%, p = 0.043). The prevalence of deafness was higher in children with ROP than those without ROP (0.4% vs. 0.1%, p = 0.049). There were significant differences in hearing impairment among the stages of ROP (p < 0.001). However, multivariate analyses and propensity score matching showed no significant association between ROP and hearing impairment at 18 months and 3 years after adjusting for prematurity-related variables (all p > 0.05). Conclusions: Among infants born with VLBW, hearing impairment was more common in those with ROP than in those without ROP at 18 months of age. However, there was no significant independent association between hearing impairment and ROP.

Extracorporeal Life Support Organization (ELSO) Guidelines for Follow-up After Neonatal and Pediatric Extracorporeal Membrane Oxygenation

Neonates and children who have survived critical illness severe enough to require extracorporeal membrane oxygenation (ECMO) are at risk for neurologic insults, neurodevelopmental delays, worsening of underlying medical conditions, and development of new medical comorbidities. Structured neurodevelopmental follow-up is recommended for early identification and prompt interventions of any neurodevelopmental delays. Even children who initially survive this critical illness without new medical or neurologic deficits remain at risk of developing new morbidities/delays at least through adolescence, highlighting the importance of structured follow-up by personnel knowledgeable in the sequelae of critical illness and ECMO. Structured follow-up should be multifaceted, beginning predischarge and continuing as a coordinated effort after discharge through adolescence. Predischarge efforts should consist of medical and neurologic evaluations, family education, and co-ordination of long-term ECMO care. After discharge, programs should recommend a compilation of pediatric care, disease-specific care for underlying or acquired conditions, structured ECMO/neurodevelopmental care including school performance, parental education, and support. Institutionally, regionally, and internationally available resources will impact the design of individual center's follow-up program. Additionally, neurodevelopmental testing will need to be culturally and lingually appropriate for centers' populations. Thus, ECMO centers should adapt follow-up program to their specific populations and resources with the predischarge and postdischarge components described here.

[Early detection of unilateral connatal hearing loss via newborn hearing screening and the implementation of the SAV-concept 2017 in lower Austria and Burgenland]

BACKGROUND

Recent studies showed the benefit or even need of hearing aids or cochlear implants in children with unilateral hearing loss to improve localization abilities and speech intelligibility. Therefore, the Audiology working group of the Austrian ENT society adopted the SAV-concept in 2017 (Screening Abklärung Versorgung von konnatalen Hörstörungen - Konzeptpapier 2017 AG Audiologie) to establish methods for testing, the mode of testing both ears, the desired schedule for the screening process and the subsequent therapy.

METHODS

The screening data were collected via questionnaires sent to all maternity and neonatal wards in different districts by responsible persons of the Austrian ENT society. Data on the implementation of the SAV concept were evaluated retrospectively based on the responses for the regions of Lower Austria and Burgenland.

RESULTS

The feedback, the implementation and responsibility for the screening program in respect of method and schedule differs throughout the federal states of Austria as well as in hospitals of state health organizations.

CONCLUSION

Austria in comparison to other European countries is missing a central documentation and tracking system via a governmental screening coordination office as the data are not generally transferred to a common birth register. Therefore, different timetables and organization for the universal new born hearing screening in the federal states as well as in state organizations were found causing a delayed diagnosis and treatment of children with unilateral hearing loss.

The prevalence of hearing loss in children with congenital diaphragmatic hernia: A longitudinal population-based study

BACKGROUND

The true prevalence of hearing loss among children with congenital diaphragmatic hernia (CDH) is unknown, with some studies reporting rates up to 60%.

PURPOSE

The purpose of this study was to determine the prevalence of hearing loss among children with CDH and compare it to age-matched controls.

METHODS

We used population-based datasets to compare the number of hearing loss diagnoses in children younger than 10 years-of-age born between 1992 and 2009 with CDH to date-of-birth matched controls without CDH. Factors associated with CDH disease severity were analyzed to determine their effect on the prevalence of hearing loss. A sensitivity analysis was performed to determine if selection bias of improved care over the course of the study affected hearing loss in CDH patients. The prevalences of hearing loss were compared using Fisher's exact tests and statistical significance was defined as p < 0.05.

RESULTS

A total of 529 children, 38 CDH cases and their 491 date-of-birth matched controls, met the inclusion criteria. Hearing loss was found in 7 children with CDH (18.4%) compared to 26 (5.3%) controls; the risk ratio (RR) of hearing loss was 3.48 (95%CI = 1.61-7.49, p = 0.006). There was no association between CDH disease severity and hearing loss.

CONCLUSIONS

CDH is associated with hearing loss compared to the general population. Our results suggest that congenital factors may contribute to hearing loss in CDH more than perinatal exposures.

LEVEL OF EVIDENCE

3.

Audiological and otologic manifestations of glutaric aciduria type I

Background

Glutaric aciduria type 1 (GA-1) is a rare disease connected with speech delay and neurological deficits. However, the audiological and otologic profiles of GA-1 have not yet been fully characterized. To our knowledge, this is the largest study of comprehensive audiological and otologic evaluation in patients with GA-1 to date.

Methods

Thirteen patients diagnosed with GA-1 between January 1994 and December 2019 with audiological, radiological and genetic manifestations were retrospectively analyzed. Hearing tests were performed in all patients. MRI was performed for radiological evaluation.

Results

Hearing loss was found in 76.9% (10/13) of GA-1 patients, including slight hearing loss in 46.1% (6/13) of patients, mild hearing loss in 15.4% (2/13) of patients, and moderate hearing loss in 7.7% (1/13) of patients. Normal hearing thresholds were seen in 23% (3/13) of patients. Patients with intensive care unit (ICU) admission history showed significantly worse hearing than those without (29.17 ± 12.47 vs 13.56 ± 3.93 dB HL, 95% CI 2.92–24.70, p = 0.0176). One patient had moderate sensorineural hearing loss and a past history of acute encephalopathic crisis. No usual causative gene mutations associated with hearing loss were found in these patients. MRI showed a normal vestibulocochlear apparatus and cochlear nerve. One patient with extensive injury of the basal ganglia on MRI after acute encephalopathic crisis was found to have moderate sensorineural hearing loss. Two patients with disability scores above 5 were found to have mild to moderate hearing impairment. No obvious correlation between macrocephaly and hearing loss was found.

Conclusion

A high prevalence of hearing impairment is found in GA-1 patients. Adequate audiological evaluation is essential for these patients, especially for those after encephalopathic crises or with ICU admission history.

Analysis of the Risk Factors Associated with Hearing Loss of Infants Admitted to a Neonatal Intensive Care Unit: A 13-Year Experience in a University Hospital in Korea

Early detection of hearing loss in neonates is important for normal language development, especially for infants admitted to the neonatal intensive care unit (NICU) because the infants in NICU have a higher incidence of hearing loss than healthy infants. However, the risk factors of hearing loss in infants admitted to the NICU have not been fully acknowledged, especially in Korea, although they may vary according to the circumstances of each country and hospital. In this study, the risk factors of hearing loss in NICU infants were analyzed by using the newborn hearing screening (NHS) and the diagnostic auditory brainstem response (ABR) test results from a 13-year period. A retrospective chart review was performed using a list of NICU infants who had performed NHS from 2004 to 2017 (n = 2404) in a university hospital in Korea. For the hearing loss group, the hearing threshold was defined as 35 dB nHL or more in the ABR test performed in infants with a 'refer' result in the NHS. A four multiple number of infants who had passed the NHS test and matched the age and gender of the hearing loss group were taken as the control group. Various patient factors and treatment factors were taken as hearing loss related variables and were analyzed and compared. From the 2404 infants involved, the prevalence of hearing loss was 1.8% (n = 43). A comparison between the hearing loss group (n = 43) and the control group (n = 172) revealed that history of sepsis, peak total bilirubin, duration of vancomycin use, days of phototherapy, and exposure to loop-inhibiting diuretics were significantly different, and can be verified as significant risk factors for hearing loss in NICU infants.

Hearing Screening Test Results of Newborns Conceived by Intracytoplasmic Sperm Injection: A Retrospective Study of Tertiary Referral Center

Objective: Assisted reproductive technologies (ART), especially intracytoplasmic sperm injection (ICSI), is associated with birth defects. However, there are few reports on hearing screening tests of these babies. We aimed to determine the association between ART and hearing loss in newborns.Materials and methods: This retrospective study examined 246 ICSI newborns between 2013 and 2015. All the patients conceived by ICSI. We examined the hearing screening results of the babies.Results: A total of 25 newborns did not pass the first screening test, including 17 by transient evoked otoacoustic emission (TEOAE) and 8 by auditory brainstem response (ABR). Ten babies did not pass the advanced examination. Total hearing loss affected 4% of ART babies.Conclusion: Hearing screening tests exposed deficient results in 4% of ICSI babies, which is ten times more frequent than spontaneously conceived newborns.

Hearing in Schoolchildren After Neonatal Exposure to a High-Dose Gentamicin Regimen

OBJECTIVE

To assess the association between gentamicin exposure in the neonatal period and hearing in school age.

METHODS

This study included children exposed to a high-dose (6 mg/kg) gentamicin regimen as neonates (2004-2012), invited for follow-up at school age, and a healthy age-matched control group. We assessed hearing with pure tone audiometry including the extended high-frequency (EHF) range. Outcomes were average hearing thresholds in the midfrequencies (0.5-4 kHz) and the EHFs (9-16 kHz). The measures of gentamicin exposure were cumulative dose and highest trough plasma concentration. We used linear regression models to assess the impact of gentamicin exposure, and other peri- and postnatal morbidities, on hearing thresholds.

RESULTS

A total of 219 gentamicin-exposed and 33 healthy-control children were included in the audiological analysis. In the gentamicin cohort, 39 (17%) had a birth weight <1500 g. Median cumulative doses and trough plasma concentrations were 30 (interquartile range 24-42) mg/kg and 1.0 (interquartile range 0.7-1.2) mg/L, respectively. Median hearing thresholds for the midfrequencies and the EHFs were 2.5 (0 to 6.3) dB hearing level and -1.7 (-5.0 to 5.0) dB hearing level, both of which were within the normal range. In an adjusted analysis, increasing hearing thresholds were associated with lower birth weight and postnatal middle-ear disease but not level of gentamicin exposure. After adjusting for birth weight, there was no difference in hearing threshold between the gentamicin-exposed cohort and healthy controls.

CONCLUSIONS

Exposure to a high-dose gentamicin regimen in the neonatal period was not associated with an increase in hearing thresholds in schoolchildren being able to complete audiometry.

Prevalence of Sensorineural Hearing Loss in Children with Palliated or Repaired Congenital Heart Disease

Background

Children with congenital heart disease (CHD) are at increased risk of neurodevelopmental deficits, and the presence of sensorineural hearing loss (SNHL) may further lead to poor language skills acquisition and speech delays. Prevalence of SNHL in the general pediatric population is estimated to be 0.2% at birth to 0.35% during adolescence. Very few studies have attempted to estimate SNHL prevalence in children who have undergone congenital heart surgery.

Methods

This retrospective study aimed to estimate SNHL prevalence in children who underwent congenital heart surgery in our institution and were followed up in our high-risk pediatric cardiology clinics for four years from 2009 to 2013. Data were collected on demographics, preoperative variables, surgical variables, and post-operative variables.

Results

SNHL prevalence in asymptomatic, palliated/repaired CHD patients followed in our high-risk clinics and undergoing routine surveillance was 11.6% (20 of 172 patients with hearing impairment). SNHL prevalence was not statistically higher in single-ventricle patients (17.2%) compared to biventricular patients (14.7%). Inotropic score in the first 24 hours of postoperative period (p=0.05), lowest arterial PaO2 (p=0.003), duration of Lasix drip (p=0), and bolus dose in days (p=0.03) were all found to be statistically significant in the hearing-impaired group. However, using logistic regression, we identified no statistically significant predictors for hearing loss.

Conclusion

The results suggest the need for routine audiology screening of all patients with complex CHD, especially those who have undergone neonatal cardiac repair/palliation at less than one year of age, irrespective of risk factors.

Evidence Supporting the Hypothesis That Inflammation-Induced Vasospasm Is Involved in the Pathogenesis of Acquired Sensorineural Hearing Loss

Sensorineural hearing loss is mainly acquired and affects an estimated 1.3 billion humans worldwide. It is related to aging, noise, infection, ototoxic drugs, and genetic defects. It is essential to identify reversible and preventable causes to be able to reduce the burden of this disease. Inflammation is involved in most causes and leads to tissue injury through vasospasm-associated ischemia. Vasospasm is reversible. This review summarized evidence linking inflammation-induced vasospasm to several forms of acquired sensorineural hearing loss. The link between vasospasm and sensorineural hearing loss is directly evident in subarachnoid haemorrhage, which involves the release of vasoconstriction-inducing cytokines like interleukin-1, endothelin-1, and tumour necrosis factor. These proinflammatory cytokines can also be released in response to infection, autoimmune disease, and acute or chronically increased inflammation in the ageing organism as in presbyacusis or in noise-induced cochlear injury. Evidence of vasospasm and hearing loss has also been discovered in bacterial meningitis and brain injury. Resolution of inflammation-induced vasospasm has been associated with improvement of hearing in autoimmune diseases involving overproduction of interleukin-1 from inflammasomes. There is mainly indirect evidence for vasospasm-associated sensorineural hearing loss in most forms of systemic or injury- or infection-induced local vascular inflammation. This opens up avenues in prevention and treatment of vascular and systemic inflammation as well as vasospasm itself as a way to prevent and treat most forms of acquired sensorineural hearing loss. Future research needs to investigate interventions antagonising vasospasm and vasospasm-inducing proinflammatory cytokines and their production in randomised controlled trials of prevention and treatment of acquired sensorineural hearing loss. Prime candidates for interventions are hereby inflammasome inhibitors and vasospasm-reducing drugs like nitric oxide donors, rho-kinase inhibitors, and magnesium which have the potential to reduce sensorineural hearing loss in meningitis, exposure to noise, brain injury, arteriosclerosis, and advanced age-related and autoimmune disease-related inflammation.

Is Asymmetric Hearing Loss a Risk Factor for Vestibular Dysfunction? Lesson From Big Data Analysis Based on the Korean National Health and Nutrition Survey

OBJECTIVE

The purpose of this study was to investigate whether asymmetric hearing loss affects vestibular function.

STUDY DESIGN

Retrospective cross-sectional study.

PATIENTS

Data from the 2010 Korean National Health and Nutrition Survey for adults aged 40 years or more were used.

INTERVENTIONS

The modified Romberg test and pure-tone audiometry were performed. Data were analyzed using a complex sample χ test of independence and complex sample logistic regression analysis.

MAIN OUTCOME MEASURES

Vestibular dysfunction and hearing thresholds.

RESULTS

The overall prevalence of vestibular dysfunction was 3.3% (95% confidence interval [CI], 2.5-4.3%). In adults more than 40 years of age, multivariate linear regression analyses showed that the odds ratio (OR) of vestibular dysfunction was 3.067 times higher than the reference for a 30-dB difference in hearing thresholds between both ears (CI, 1.481-6.351; p = 0.007) after adjusting for factors associated with vestibular dysfunction. Among these individuals, the risk of equilibrium disturbance was higher in the presence of low-frequency asymmetric hearing loss (OR, 2.148; CI, 1.216-3.793; p = 0.009); on the other hand, high-frequency asymmetry did not lead to a higher risk.

CONCLUSIONS

As low-frequency asymmetric hearing thresholds tend to coexist with vestibular dysfunction in adults, those with asymmetric hearing loss should be closely monitored.

Risk factors for hearing impairment in neonates in South Africa: scoping the context for newborn hearing screening planning

PURPOSE

The current study aimed to describe the medical case history factors in a group of neonates admitted to high care and Kangaroo Mother Care wards at two hospitals in Gauteng, South Africa and to explore the relationship between specific case history factors and audiological outcomes.

METHODS

This study was part of a bigger study titled "Early detection of hearing loss: exploring risk-based hearing screening within a developing country context" where all case history data were recorded from participant medical files at the time of an initial hearing screening, through the use of a case history form that was developed for this study. Results were analyzed using descriptive statistics. The relationship between case history factors and audiological outcomes was analyzed using Fisher's exact test.

RESULTS

Findings revealed that, of all the case history data, preterm birth (95.7%), exposure to ototoxic medication (87.7%), neonatal jaundice (NNJ) (80.6%), and birthweight below 1500 g (66.7%) were the most frequently occurring case history factors in this South African sample. No statistically significant association was found between these frequently occurring case history factors and the repeat hearing screening outcomes in this sample.

CONCLUSIONS

Risk factors for hearing impairment cannot be viewed in isolation but should be considered in relation to their interaction with multiple other risk factors. Contextually understanding the profile of high risk has implications for medical intervention, as well as for the field of Audiology where planning for early identification and intervention services for hearing impairment is vital. Such contextually relevant evidence allows for a snap shot of how this population presents, what their needs and requirements are, and their possible future requirements; hence, raising important planning implications for the department of health and for targeted newborn hearing screening as well as early childhood intervention within the South African context.

Prevalence of permanent childhood hearing loss detected at the universal newborn hearing screen: Systematic review and meta-analysis

CONTEXT

Permanent childhood hearing loss (PCHL) can affect speech, language, and wider outcomes. Adverse effects are mitigated through universal newborn hearing screening (UNHS) and early intervention.

OBJECTIVE

We undertook a systematic review and meta-analysis to estimate prevalence of UNHS-detected PCHL (bilateral loss ≥26 dB HL) and its variation by admission to neonatal intensive care unit (NICU). A secondary objective was to report UNHS programme performance (PROSPERO: CRD42016051267).

DATA SOURCES

Multiple electronic databases were interrogated in January 2017, with further reports identified from article citations and unpublished literature (November 2017).

STUDY SELECTION

UNHS reports from very highly-developed (VHD) countries with relevant prevalence and performance data; no language or date restrictions.

DATA EXTRACTION

Three reviewers independently extracted data and assessed quality.

RESULTS

We identified 41 eligible reports from 32 study populations (1799863 screened infants) in 6195 non-duplicate references. Pooled UNHS-detected PCHL prevalence was 1.1 per 1000 screened children (95% confidence interval [CI]: 0.9, 1.3; I2 = 89.2%). This was 6.9 times (95% CI: 3.8, 12.5) higher among those admitted to NICU. Smaller studies were significantly associated with higher prevalences (Egger's test: p = 0.02). Sensitivity and specificity ranged from 89-100% and 92-100% respectively, positive predictive values from 2-84%, with all negative predictive values 100%.

LIMITATIONS

Results are generalisable to VHD countries only. Estimates and inferences were limited by available data.

CONCLUSIONS

In VHD countries, 1 per 1000 screened newborns require referral to clinical services for PCHL. Prevalence is higher in those admitted to NICU. Improved reporting would support further examination of screen performance and child demographics.

Risk Factors and Prognostic Factors of Hearing Impairment in Neonatal Intensive Care Unit-Treated Infants

BACKGROUND

Infants admitted to the neonatal intensive care unit (NICU) have a higher incidence of congenital hearing loss compared with the healthy newborn population.

OBJECTIVES

To clarify the relationship between risk factors for hearing impairment in NICU-treated infants and deterioration of the auditory brainstem response (ABR) threshold during childhood.

METHOD

We screened 1,071 high-risk infants admitted to the NICU for hearing impairment. One-hundred forty-eight infants exhibited an abnormal ABR threshold of ≥40 dB nHL. We analyzed the correlation of change in ABR threshold with risk factors for future hearing impairment.

RESULTS

Among infants treated in the NICU, 148 (13.8%) exhibited an ABR threshold of ≥40 dB nHL; 107 of these 148 (72.3%) showed hearing change in the process (102 showed improvement to normal hearing level, whereas 5 showed further deterioration). Our analysis showed that the factors contributing to the elevation of ABR threshold were oxygen administration and chromosomal aberrations.

CONCLUSIONS

Factors related to the elevation of ABR threshold were oxygen administration and the presence of chromosomal aberrations. Awareness of risk factors that are more likely to cause hearing loss in infants may aid in follow-up treatment of these children.

Risk factors for failure in the newborn hearing screen test in very preterm twins

BACKGROUND

We aimed to identify prenatal and postnatal risk factors associated with abnormal newborn hearing screen (NHS) results and subsequently confirmed sensorineural hearing loss (SNHL) in preterm twin neonates.

METHODS

Electronic medical records of 159 twin neonates who were born alive after ≤32 weeks were retrospectively reviewed for hearing loss in both ears. Histopathologic examination of the placenta was performed and clinical data, including method of conception and factors specific to twins, were retrieved from a computerized perinatal database. The main outcome measure was failure to pass the NHS test. The generalized estimation equations model was used for twins.

RESULTS

Thirty-two neonates (20.1%) had a "refer" result, and, on the confirmation test, permanent SNHL was identified in 4.4% (7/159) of all neonates. Neonates who had a "refer" result on the NHS test were more likely to be of lower birth weight, more likely to have been conceived with the use of in vitro fertilization (IVF), and more likely to have higher rates of intraventricular hemorrhage (IVH) and bronchopulmonary dysplasia. However, monochorionic placentation, death of the co-twin, or being born first was not associated with a "refer" result on the NHS test. Multivariable logistic regression revealed that conception after IVF and the presence of IVH were the only variables to be statistically significantly associated with "refer" on the NHS test. No parameters studied were found to be significantly different between the SNHL and no SNHL groups, probably because of the relatively small number of cases of SNHL.

CONCLUSION

In preterm twin newborns, IVF and the presence of IVH were independently associated with an increased risk of abnormal NHS results, whereas the factors specific to twins were not associated with abnormal NHS results.

Prolonged furosemide exposure and risk of abnormal newborn hearing screen in premature infants

BACKGROUND

At very high doses, furosemide is linked to ototoxicity in adults, but little is known about the risk of hearing loss in premature infants exposed to furosemide.

AIMS

Evaluate the association between prolonged furosemide exposure and abnormal hearing screening in premature infants.

STUDY DESIGN

Using propensity scoring, infants with prolonged (≥28 days) exposure to furosemide were matched to infants never exposed. The matched sample was used to estimate the impact of prolonged furosemide exposure on the probability of an abnormal hearing screen prior to hospital discharge.

SUBJECTS

A cohort of infants 501-1250 g birth weight and 23-29 weeks gestational age discharged home from 210 neonatal intensive care units in the United States (2004-2013).

OUTCOME MEASURES

We defined abnormal hearing screen as a result of either "fail" or "refer" for either ear.

RESULTS

Altogether, 1020 infants exposed to furosemide for ≥28 days were matched to 790 unique infants never exposed, yielding a total of 1042 matches due to sampling with replacement and propensity score ties. Matching resulted in a population similar in baseline characteristics. After adjusting for covariates, the proportion of infants with an abnormal hearing screen in the furosemide-exposed group was not significantly higher than the never-exposed group (absolute difference 3.0% [95% CI -0.2-6.2%], P = 0.07).

CONCLUSIONS

Prolonged furosemide exposure was associated with a positive, but not statistically significant, difference in abnormal hearing screening in premature infants. Additional studies with post-hospital discharge audiology follow-up are needed to further evaluate the safety of furosemide in this population.

Sensorineural and conductive hearing loss in infants diagnosed in the program of universal newborn hearing screening

OBJECTIVE

The aim of this study was to analyze infants diagnosed with sensorineural or conductive hearing deficit and to identify risk factors associated with these defects.

MATERIAL AND METHODS

A retrospective analysis of infants diagnosed with hearing deficit based on the database of the universal newborn hearing screening program and medical records of the patients.

RESULTS

27 935 infants were covered by the universal neonatal hearing screening program. 109 (0.39%) were diagnosed with hearing deficit and referred for treatment and rehabilitation. 56 (51.4%) children were diagnosed with conductive, 38 (34.9%) with sensorineural and 15 (13.8%) with mixed type of hearing deficit. Children with sensorineural hearing deficit more frequently suffered from hyperbilirubinemia (p < 0.05), while infants with conductive hearing loss were more frequently diagnosed with isolated craniofacial anomalies (p < 0.05). The prevalence of other risk factors did not differ between the groups. Sensorineural hearing deficit occurred almost 3 times more often bilaterally than unilaterally (p < 0.05). In other types of hearing deficit, the difference was not significant. In children with conductive and mixed type of hearing loss the impairment was mainly mild while among those with sensorineural hearing deficit in almost 45% it was severe and profound (p < 0.05). When analyzing the consistency between hearing screening test by means of otoacoustic emissions and the final diagnosis of hearing deficit we found that the highest agreement rate was observed in children with sensorineural hearing loss (p < 0.01).

CONCLUSIONS

The prevalence of most risk factors of hearing deficit was similar in children with sensorineural, conductive and mixed type of hearing loss, only hyperbilirubinemia seemed to predispose to sensorineural hearing deficit and isolated craniofacial malformations seemed to be associated with conductive hearing loss. Sensorineural hearing deficit usually occurred bilaterally and was severe or profound, while conductive and mixed type of hearing deficit were most often of mild degree. Most children with the final diagnosis of sensorineural hearing deficit had positive result of hearing screening by means of otoacoustic emissions.

Hearing impairment in premature newborns-Analysis based on the national hearing screening database in Poland

Objectives

The incidence of sensorineural hearing loss is between 1 and 3 per 1000 in healthy neonates and 2–4 per 100 in high-risk infants. The national universal neonatal hearing screening carried out in Poland since 2002 enables selection of infants with suspicion and/or risk factors of hearing loss. In this study, we assessed the incidence and risk factors of hearing impairment in infants ≤33 weeks’ gestational age (wga).

Methods

We analyzed the database of the Polish Universal Newborns Hearing Screening Program from 2010 to 2013. The study group involved 11438 infants born before 33 wga, the control group—1487730 infants. Screening was performed by means of transient evoked otoacoustic emissions. The risk factors of hearing loss were recorded. Infants who failed the screening test and/or had risk factors were referred for further audiological evaluation.

Results

Hearing deficit was diagnosed in 11% of infants ≤25 wga, 5% at 26–27 wga, 3.46% at 28 wga and 2–3% at 29–32 wga. In the control group the incidence of hearing deficit was 0.2% (2.87% with risk factors). The most important risk factors were craniofacial malformations, very low birth weight, low Apgar score and mechanical ventilation. Hearing screening was positive in 22.42% newborns ≤28 wga and 10% at 29–32 wga and in the control group.

Conclusions

Hearing impairment is a severe consequence of prematurity. Its prevalence is inversely related to the maturity of the baby. Premature infants have many concomitant risk factors which influence the occurrence of hearing deficit.

An analysis of hearing screening test results in 2291 premature infants of Chinese population

OBJECTIVE

The aim of this study was to analyze the hearing screening program among preterm infants as well as to identify risk factors associated with failing primary newborn hearing screening.

METHODS

The retrospectively selected population included all preterm infants who had primary hearing screening in a neonatal ward from January 1st, 2013 to December 31st, 2015 at West China Second University Hospital, Sichuan University. The newborn hearing screening (NHS) procedure was performed in all preterm infants by automated auditory brainstem response (AABR). Infants who failed the primary hearing screening received a second screening at 42 days after birth. Infants who failed both tests were referred to a tertiary audiology center for diagnostic confirmation and management before 6 months of age. The final diagnosis for referred infants was obtained by telephone follow-up. The risk factors associated with failure to pass the primary hearing screen were evaluated and analyzed for preterm infants.

RESULTS

Among 2291 preterm infants recruited, 155 infants (6.8%) failed the primary hearing screening with an abnormal AABR. Of these 155 infants, 113 (72.9%) passed the secondary screening. At the end of the follow-up, 1 infant (0.04%) was diagnosed with hearing loss, 3 infants had delayed language development, and 40 infants were lost to follow up. Multivariate regression analysis revealed that gestational age ≤32 weeks (Odds ratio [OR] = 2.093, 95% confidence interval [CI] 1.370-3.196), super hyperbilirubinemia (≥25 mg/dl) (OR = 3.560, 95% CI 1.009-12.560), and respiratory failure (OR = 1.971, 95% CI 1.188-3.265) were associated with failure to pass newborn hearing screening.

CONCLUSION

The prevalence of failure to pass primary hearing screening among preterm infants was 6.8% in our study, and we found a relatively low prevalence of hearing loss (0.04%). Super hyperbilirubinemia, gestational age ≤32weeks, and respiratory failure were risk factors associated with failure of preterm infants to pass the primary hearing screening. Our results suggest that preterm infants with hyperbilirubinemia, gestational age ≤32 weeks, and respiratory failure should be closely followed.

Universal newborn hearing screening: methods and results, obstacles, and benefits

The incidence of sensorineural hearing loss ranges from 1 to 3 per 1,000 live births in term healthy neonates, and 2-4 per 100 in high-risk infants, a 10-fold increase. Early identification and intervention with hearing augmentation within 6 mo yields optimal effect. If undetected and without treatment, significant hearing impairment may negatively impact speech development and lead to disorders in psychological and mental behaviors. Hearing screening programs in newborns enable detection of hearing impairment in the first days after birth. Programs to identify hearing deficit have significantly improved over the two decades, and their implementation continues to grow throughout the world. Initially based on risk factors, these programs identified only 50-75% of infants with hearing loss. Current recommendations are to conduct universal hearing screening in all infants. Techniques used primarily include automated auditory brainstem responses and otoacoustic emissions that provide noninvasive recordings of physiologic auditory activity and are easily performed in neonates and infants. The aim of this review is to present the objectives, benefits, and results of newborn hearing screening programs including the pros and cons of universal vs. selective screening. A brief history and the anticipated future development of these programs will also be discussed.

An effective compromise between cost and referral rate: A sequential hearing screening protocol using TEOAEs and AABRs for healthy newborns

OBJECTIVE

This study evaluated the efficacy of a sequential hearing screening protocol using transient evoked otoacoustic emission (TEOAE) and automated auditory brainstem response (AABR) tests in healthy newborns.

DESIGN

A TEOAE screening was performed during the first 48-72 h of life. If the infants failed, an AABR test was performed at the same time, and they were referred for a TEOAE rescreening at six weeks old. The results of screening Protocol 1 (only TEOAE) were compared with those of screening Protocol 2 (sequential TEOAE + AABR screenings for the first screening and TEOAE for the rescreening).

STUDY SAMPLE

A total of 1062 healthy newborns were enrolled in this research.

RESULTS

For Protocol 1, the first screening and rescreening referral rates were 11.1% and 2.2%, respectively. In contrast, for Protocol 2, the referral rates were significant lower at 3.8% and 0.9%, respectively. Using the two protocols, six infants were diagnosed with hearing loss (0.57%).

CONCLUSIONS

Adding simultaneous AABR tests for infants who fail TEOAE testing at the first screening stage can significantly reduce referral rates without increasing misdiagnosis rates. Although this sequential screening process involves slightly more time and has a higher cost than TEOAE alone, its greater accuracy compensates for this difference.

Newborn hearing screening in Queensland 2009-2011: Comparison of hearing screening and diagnostic audiological assessment between term and preterm infants

AIM

This study compares rates and timing of newborn hearing screening outcomes, audiological assessment and hearing loss diagnosis between infants of different gestational age groups. Early identification and management of sensorineural hearing loss (SNHL), ideally by 3-6 months of age, facilitates speech and language optimisation. Literature stratifying hearing screening and diagnostic audiology assessment by gestational age groups is lacking.

METHODS

Subjects were infants with recorded gestational ages receiving newborn hearing screening in Queensland between 2009 and 2011. Data were provided through the Queensland Healthy Hearing database. Infants were analysed in <34 weeks, 34-36⁺⁶ weeks, 37-38⁺⁶ weeks and ≥39 weeks gestational age groups.

RESULTS

Infants (175 911) were eligible for analysis, 7.9% being preterm. Per 1000 infants analysed, bilateral SNHL of >40 dB occurred in 2.4 for <34, 1.4 for 34-36⁺⁶ , 0.7 for 37-38⁺⁶ and 0.7 for ≥39 weeks gestation. Diagnoses attributable to newborn hearing screening direct referral were 93.1% for bilateral >40 dB SNHL and 88.2% for other hearing loss. Relative to term, preterm infants had a higher incidence of direct and targeted surveillance referrals, audiology assessment and hearing loss diagnosis. Preterm infants were screened later after birth.

CONCLUSIONS

Specific hearing screening and diagnosis characteristics differed between preterm infants <34 and 34-36⁺⁶ weeks gestation, and term infants. Consideration of unique gestational age strata characteristics supports care individualisation. Preterm infants represent a diagnostic challenge, with higher rates of bilateral >40 dB SNHL than term but correspondingly higher false positive results on screening, justifying vigilant monitoring. Focused research into specific risk factors in preterm infants is warranted.

Diagnosis and Management of Congenital Sensorineural Hearing Loss

Hearing loss is the most common sensory disorder in the USA. The diagnosis of congenital hearing loss starts with newborn hearing screening, which is best performed with auditory brainstem evoked responses in order to avoid the risk of missing auditory neuropathy spectrum disorder. A careful history and physical exam can occasionally help reveal the etiology for congenital hearing loss. Imaging studies, either CT temporal bones or MRI of the internal auditory canals without gadolinium, and genetic testing, in particular for connexin 26, connexin 30, and Pendred syndrome, are the most useful diagnostic tests. Management of congenital hearing loss involves early fitting of amplification. Early cochlear implantation, preferably before 2 years of age, should be strongly considered for children with bilateral severe hearing loss.

Bilirubin-Induced Audiologic Injury in Preterm Infants

Although hyperbilirubinemia is extremely common among neonates and is usually mild and transient, it sometimes leads to bilirubin-induced neurologic damage (BIND). The auditory pathway is highly sensitive to the effects of elevated total serum/plasma bilirubin (TB) levels, with damage manifesting clinically as auditory neuropathy spectrum disorder. Compared to full-term neonates, preterm neonates are more susceptible to BIND and suffer adverse effects at lower TB levels with worse long-term outcomes. Furthermore, although standardized guidelines for management of hyperbilirubinemia exist for term and late preterm neonates, similar guidelines for neonates less than 35 weeks gestational age are limited.

Antenatal factors modulate hearing screen failure risk in preterm infants

OBJECTIVE

The objective of this study was to characterise the effects of antenatal inflammatory factors and maternal therapies on neonatal hearing screen outcomes in very low birthweight infants.

METHODS

We conducted a retrospective study of a cohort of infants <33 weeks' gestational age and <1501 g birth weight prospectively enrolled between 1999 and 2003 for whom placental pathology, cord blood interleukin (IL) 6, IL-1ß, tumour necrosis factor-α and neonatal hearing screen results were available.

RESULTS

Of 289 infants with documented hearing screen results, 244 (84%) passed and 45 (16%) failed the hearing screen (unilateral, N=25 (56%); bilateral, N=20 (44%)). In the final logistic model, the fetal inflammatory response syndrome defined as the presence of fetal vasculitis and/or cord serum IL-6>18.2 pg/mL was the factor with greatest risk for hearing screen failure (OR 3.62, 95% CI 1.38 to 9.5). A patent ductus arteriosus treated with indomethacin significantly increased the risk (OR 3.3, 95% CI 1.3 to 8.26), while combined maternal steroid and magnesium sulfate exposure (0.37, 95% CI 0.11 to 0.81) reduced the risk for hearing screen failure.

CONCLUSIONS

Intrauterine infection with a fetal inflammatory response is a risk factor for neonatal hearing loss while maternal therapies significantly reduced the risk of neonatal hearing loss in very low birthweight infants.

Newborn hearing screening programme in Belgium: a consensus recommendation on risk factors

Background

Understanding the risk factors for hearing loss is essential for designing the Belgian newborn hearing screening programme. Accordingly, they needed to be updated in accordance with current scientific knowledge. This study aimed to update the recommendations for the clinical management and follow-up of newborns with neonatal risk factors of hearing loss for the newborn screening programme in Belgium.

Methods

A literature review was performed, and the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system assessment method was used to determine the level of evidence quality and strength of the recommendation for each risk factor. The state of scientific knowledge, levels of evidence quality, and graded recommendations were subsequently assessed using a three-round Delphi consensus process (two online questionnaires and one face-to-face meeting).

Results

Congenital infections (i.e., cytomegalovirus, toxoplasmosis, and syphilis), a family history of hearing loss, consanguinity in (grand)parents, malformation syndromes, and foetal alcohol syndrome presented a ‘high’ level of evidence quality as neonatal risk factors for hearing loss. Because of the sensitivity of auditory function to bilirubin toxicity, hyperbilirubinaemia was assessed at a ‘moderate’ level of evidence quality. In contrast, a very low birth weight, low Apgar score, and hospitalisation in the neonatal intensive care unit ranged from ‘very low’ to ‘low’ levels, and ototoxic drugs were evidenced as ‘very low’. Possible explanations for these ‘very low’ and ‘low’ levels include the improved management of these health conditions or treatments, and methodological weaknesses such as confounding effects, which make it difficult to conclude on individual risk factors. In the recommendation statements, the experts emphasised avoiding unidentified neonatal hearing loss and opted to include risk factors for hearing loss even in cases with weak evidence. The panel also highlighted the cumulative effect of risk factors for hearing loss.

Conclusions

We revised the recommendations for the clinical management and follow-up of newborns exhibiting neonatal risk factors for hearing loss on the basis of the aforementioned evidence-based approach and clinical experience from experts. The next step is the implementation of these findings in the Belgian screening programme.

Electronic supplementary material

The online version of this article (doi:10.1186/s12887-015-0479-4) contains supplementary material, which is available to authorized users.

Audiologic impairment associated with bilirubin-induced neurologic damage

Hyperbilirubinemia occurs commonly in neonates and is usually mild and transient, with no long-lasting sequelae. However, bilirubin-induced neurologic damage may occur in some infants. The auditory pathway is the most sensitive part of the central nervous system to bilirubin-induced toxicity, and permanent sequelae may result from only moderately elevated total serum/plasma bilirubin levels. The damage to the auditory system occurs primarily within the brainstem and cranial nerve VIII, and manifests clinically as auditory neuropathy spectrum disorder.

Is hearing loss in infants associated with risk factors? Evaluation of the frequency of risk factors

OBJECTIVES

To evaluate the frequency of risk factors and their influence on the evoked otoacoustic emission (OAE) of infants.

METHODS

All newborns between November 2009 and June 2012 in Haydarpaşa Numune Education and Research Hospital were tested on distortion evoked OAE screening test. Total of 2,284 infants were examined. Sex, maternal infectious disease, birth type (vaginal birth or caesarean sectio), birth weight, familial hearing loss, intermarriage of parents, hyperbilirubinemia, intensive care were analyzed as risk factors.

RESULTS

Total of 2,284 neonates were screened (1,220 males and 1,064 females) for the presence of OAE in both ears. Vaginal delivery, maternal infections during pregnancy, intermarriage of parents relative, low birth weight(<1,500 g) are related risk factors to failure of screening with OAE in our study. There was no statistically significant difference in sex ratios, birth weight, familial hearing loss, hyperbilirubinemia, and intensive care stay.

CONCLUSION

Risk factors are only as useful as their predictive power. Not enough is known about which risk factors are relevant, which babies have the risk factors, or which babies will fail to attend follow-up, the effectiveness of targeted hearing loss testing is questionable at this point in time. A system needs to be developed to clarify which risk factors are discoverable, predictive and useful.

Sensorineural hearing loss in children: the association with Apgar score. A registry-based study of 392,371 children in Norway

OBJECTIVES

The causes of congenital permanent hearing loss in children are insufficiently understood. We studied the association of Apgar score 5 min after birth with sensorineural hearing loss diagnosed before the age of 5 years.

METHODS

We performed an epidemiological cohort study with data obtained by linkage between The Medical Birth Registry of Norway and the Norwegian County Registry of Children with Hearing Loss. Cases were 327 children born in Norway during the period 1978-1998 with sensorineural hearing loss. Controls were all children in Norway without sensorineural hearing loss born in the same counties and during the same period as the cases (n=392,044). The associations of Apgar score 5 min after birth with sensorineural hearing loss were estimated as odds ratios (OR) with 95% confidence intervals (CI) by applying logistic regression analyses.

RESULTS

Among children with sensorineural hearing loss 0.9% (3/327) had Apgar score<3, whereas that was true for 0.1% (304/392044) of children without hearing loss (p=0.001, chi square test). The aOR for sensorineural hearing loss was 7.5 [95% CI 2.3-, 24.2] comparing Apgar score<3 to Apgar score 10, after adjustment for birthweight and concurrent birth defects. Most children with sensorineural hearing loss (90%) had Apgar score>8 five minutes after birth.

CONCLUSIONS

Low Apgar score was associated with childhood sensorineural hearing loss. However, most children with sensorineural hearing loss, had Apgar score>8.

Prognostic value of newborn hearing screening in patients with myelomeningocele

OBJECT

Brainstem dysfunction occurs in a minority of patients with myelomeningocele (MMC), most of whom have Chiari Type II malformation. Some surgeons advocate early identification of these patients for craniocervical decompression to avoid significant mortality. The auditory brainstem response has been found to be abnormal in most children with MMC. The present study examines whether failure of routine newborn hearing screening (NHS) predicts brainstem dysfunction in MMC patients.

METHODS

The charts of 40 newborns with MMC and 50 newborns without MMC who stayed in the neonatal intensive care unit were reviewed. Results of NHS, brainstem symptoms, birth demographics, and surgical history were retrospectively examined. Differences in the presence and onset of brainstem symptoms by NHS result were assessed.

RESULTS

Failure of NHS was more common among newborns with MMC who developed brainstem symptoms (31%, 4 of 13 patients) than among newborns without MMC (0%, 0 of 50 patients; p = 0.001). Among the 40 newborns with MMC, brainstem symptoms were more common in those who failed NHS (80%, 4 of 5 patients) than in those who passed (26%, 9 of 35 patients; p = 0.031). Respiratory symptom onset occurred later in patients who failed NHS (median 16 months) than among those who passed (median 0 months; p = 0.022). The positive and negative predictive values of NHS for brainstem dysfunction in MMC were 0.80 and 0.74, respectively.

CONCLUSIONS

Results of NHS may help predict future brainstem dysfunction in patients with MMC and may be useful to incorporate into prognostic assessment and surgical decision making.

[Assessment of levels of otoacoustic emission response in neonates with perinatal asphyxia]

Objective:

To evaluate the effects of perinatal asphyxia on the level of the response to transient otoacoustic emissions in infants.

Methods:

Otoacoustic emissions in 154 neonates were performed: 54 infants who suffered asphyxia at birth, measured by Apgar score and medical diagnosis, and 100 infants without risk were compared. Scores less than 4 in the first minute and/or less than 6 in the fifth minute were considered as "low Apgar". Statistical analysis of the data was performed using the Kruskal, Wilcoxon, and Mann-Whitney nonparametric tests.

Results:

Lower levels of response were observed in transient otoacoustic emission in the group that suffered perinatal asphyxia, with significant values for the frequencies 2,000, 3,000, and 4,000 Hz in the right ear, and 2,000 and 4,000 Hz in the left ear.

Conclusions:

The analysis of the intrinsic characteristics of the otoacoustic emissions evidenced low performance of outer hair cells in neonates who had perinatal asphyxia, which may affect the development of listening skills in this population.

Sensorineural hearing loss in very low birth weight infants with histological chorioamnionitis

OBJECTIVE

Histological chorioamnionitis (HCAM) has been associated with inflammatory diseases of preterm infants. Recently we have observed that it increased the risk of speech delay and hearing loss. So the aim of this study was to evaluate the relationship between sensorineural hearing loss (SNHL) of VLBW infants and HCAM.

METHODS

We performed an observational study on VLBW infants admitted to the NICU of Padua. Each patient with HCAM was matched with one control without HCAM. All infants underwent hearing screening before discharge by means of automated transient-evoked otoacustic emissions and automated auditory brainstem responses, which were repeated at 3 and 6 months of age with tympanometry measurement. Incidence of SNHL at 6 months of age was compared in the 2 groups and risk factors for hearing loss were studied.

RESULTS

Two of 77 (2.6%) newborns with HCAM e 6/73 (8.2%) without it presented SNHL at 6 months of corrected age (p = 0.16). Multivariable logistic regression analysis identified surgical ligation of patent ductus arteriosus (PDA) as independent predictors of SNHL (OR: 5.75, 95% CI 1.34-24.84, p = 0.02), whereas the effect of HCAM on SNHL was only near to statistical significance level.

CONCLUSIONS

Surgical ligation of PDA is associated with an increased risk of SNHL in VLBW infants, regardless of HCAM.

Newborn hearing screening and early diagnostic in the NICU

The aim was to describe the outcome of neonatal hearing screening (NHS) and audiological diagnosis in neonates in the NICU. The sample was divided into Group I: neonates who underwent NHS in one step and Group II: neonates who underwent a test and retest NHS. NHS procedure was automated auditory brainstem response. NHS was performed in 82.1% of surviving neonates. For GI, referral rate was 18.6% and false-positive was 62.2% (normal hearing in the diagnostic stage). In GII, with retest, referral rate dropped to 4.1% and false-positive to 12.5%. Sensorineural hearing loss was found in 13.2% of infants and conductive in 26.4% of cases. There was one case of auditory neuropathy spectrum (1.9%). Dropout rate in whole process was 21.7% for GI and 24.03% for GII. We concluded that it was not possible to perform universal NHS in the studied sample or, in many cases, to apply it within the first month of life. Retest reduced failure and false-positive rate and did not increase evasion, indicating that it is a recommendable step in NHS programs in the NICU. The incidence of hearing loss was 2.9%, considering sensorineural hearing loss (0.91%), conductive (1.83%) and auditory neuropathy spectrum (0.19%).

Long-term outcome of children treated with neonatal extracorporeal membrane oxygenation: increasing problems with increasing age

As more and more critically ill neonates survive, it becomes important to evaluate long-term morbidity. This review aims to provide an up-to-date overview of medical and neurodevelopmental outcomes in children who as neonates received treatment with extracorporeal membrane oxygenation (ECMO). Most patients-except those with congenital diaphragmatic hernia-have normal lung function and normal growth at older age. Maximal exercise capacity is below normal and seems to deteriorate over time in the CDH population. Gross motor function problems have been reported until school age. Although mental development is usually favorable within the first years and cognition is normal at school age, many children experience problems with working speed, spatial ability tasks, and memory. In conclusion, children who survived neonatal treatment with ECMO often encounter neurodevelopmental problems at school age. Long-term follow-up is needed to recognize problems early and to offer appropriate intervention.

Aminoglycoside toxicity in neonates: something to worry about?

Toxicity has limited the use of aminoglycosides and adult studies report high rates of both ototoxicity and nephrotoxicity. Conversely paediatric studies have shown lower rates and extended interval dosing may have reduced toxicity further. We review the animal and human evidence for aminoglycoside toxicity in neonates including mechanisms, measurement and rates of toxicity; and differences between aminoglycosides and dosing regimens. We discuss genetic susceptibility and the impact of other synergistic effects.

Neural conduction abnormality in the brain stem and prevalence of the abnormality in late preterm infants with perinatal problems

Neurodevelopment in late preterm infants has recently attracted considerable interest. The prevalence of brain stem conduction abnormality remains unknown. We examined maximum length sequence brain stem auditory evoked response in 163 infants, born at 33-36 weeks gestation, who had various perinatal problems. Compared with 49 normal term infants without problems, the late preterm infants showed a significant increase in III-V and I-V interpeak intervals at all 91-910/s clicks, particularly at 455 and 910/s (p < 0.01-0.001). The I-III interval was slightly increased, without statistically significant difference from the controls at any click rates. These results suggest that neural conduction along the, mainly more central or rostral part of, auditory brain stem is abnormal in late preterm infants with perinatal problems. Of the 163 late preterm infant, the number (and percentage rate) of infants with abnormal I-V interval at 91, 227, 455, and 910/s clicks was, respectively, 11 (6.5%), 17 (10.2%), 37 (22.3%), and 31 (18.7%). The number (and percentage rate) of infants with abnormal III-V interval at these rates was, respectively, 10 (6.0%), 17 (10.2%), 28 (16.9), and 36 (21.2%). Apparently, the abnormal rates were much higher at 455 and 910/s clicks than at lower rates 91 and 227/s. In total, 42 (25.8%) infants showed abnormal I-V and/or III-V intervals.

CONCLUSION

Conduction in, mainly in the more central part, the brain stem is abnormal in late preterm infants with perinatal problems. The abnormality is more detectable at high- than at low-rate sensory stimulation. A quarter of late preterm infants with perinatal problems have brain stem conduction abnormality.

[Pedaudiological diagnostics in the first year of life . Clinical follow-up, risk factors, and middle ear function]

The universal neonatal hearing screening (UNHS) program demands detection of hearing loss within the first 3 months of life. Practicability and different screening methods should be evaluated. Thus, 617 patients (329 m., 288 w.) were analyzed; 246 children were referred in the UNHS, 389 with risk factors. In 459 children (74%), automated auditory brainstem response (ABR) screening in our department excluded hearing loss, thereof 129 (21%) underwent diagnostic auditory brainstem-evoked audiometry responses: 20 (16%) showed normal and 109 (84%) elevated ABR thresholds. A total of 91 children (83%) received hearing aids and 11 children (10%) treatment of middle ear effusion. Hearing loss was diagnosed in 18% of all children, 24% with UNHS referral and 34% with both referral and risk factors. Craniofacial anomalies, premature birth < 32 weeks of pregnancy, and syndromes were the most frequent risk factors. Reevaluation by ABR showed an improvement to normal hearing in 3 (of 14) children. The 226 Hz compared to 1,000 Hz-tympanometry showed different specificity (95.5 vs. 85.5%) and sensitivity (32.5 vs. 57.1%). Diagnosis within 3 months is possible, but very challenging in children with risk factors.

Sensorineural hearing loss and language development following neonatal extracorporeal membrane oxygenation

OBJECTIVES

To determine the prevalence of hearing loss in school-age children who have undergone neonatal extracorporeal membrane oxygenation treatment and to identify any effects of hearing loss on speech- and language development [corrected] .

DESIGN

Prospective longitudinal follow-up study within the framework of a structured post-extracorporeal membrane oxygenation follow-up program.

SETTING

Outpatient clinic of a level III university hospital.

RESULTS

Tone audiometry was performed by standardized protocol in 136 children aged 5-12 yrs. Hearing loss was considered clinically significant when >20 dB. Hearing was normal in 75.7% of children. Five children (3.7%) had bilateral sensorineural or combined hearing loss; three of them received special audiological care (2.2% of total sample). Of the 24 children with congenital diaphragmatic hernia, 19 (79.2%) had normal hearing and only two (8.3%) had mild sensorineural hearing loss, unilateral in one of them. Follow-up at 24 months of age had shown normal verbal and nonverbal developmental scores. Language development and intelligence median (range) scores at 5 yrs of age were also normal: receptive language development 104 (55-133), syntactical development 104 (68-132), and lexical development 101 (50-141) for 89 children; intelligence quotient 104 (68-132) for 106 children. Scores did not differ among those with normal hearing, mild hearing loss, and moderate-to-severe hearing loss (p = 0.800, p = 0.639, p = 0.876, and p = 0.886, for the respective developmental tests).

CONCLUSIONS

We found normal language development and intelligence in a cohort of neonatal extracorporeal membrane oxygenation survivors. The prevalence of bilateral sensorineural hearing loss was in accordance with that of a larger series in the United States-which exceeds the prevalence in the normal population.

Implementation and results of bedside hearing screening with automated auditory brainstem response in the neonatal intensive care unit

AIM

To evaluate implementation and results of neonatal hearing screening with automated auditory brainstem response (AABR) by bedside nurses in a single-centre neonatal intensive care unit (NICU).

METHODS

Retrospective review of charts of 2074 newborns admitted over a 4-year period.

RESULTS

One thousand eight hundred and 24 newborns (88%) were screened. A 'pass' result was obtained in 1761 patients (96.5%). From 63 infants with 'refer', 40 were tested with auditory brainstem response: in 28 hearing loss was confirmed. Three hundred and nine neonates were screened before postmenstrual age (PMA) of 34 weeks: 78% successfully passed the first test. Sixty-seven infants with 'refer' at the first test before PMA of 34 weeks were re-evaluated: 48 had normal hearing tests, 24 of whom still younger than 34 weeks. For 12 of 19 infants with 'refer' before 34 weeks, follow-up was available: in 7 hearing loss was confirmed.

CONCLUSION

Neonatal hearing screening with AABR can be easily performed by the bedside nurse in the NICU even in premature babies before 34 weeks PMA. A 'pass' result can be obtained in almost 80% of them; a 'refer' result at that age, however, must be interpreted cautiously, as false 'refer' occurred in 5/12 of these infants.