Hearing loss in children with osteogenesis imperfecta

Osteogenesis imperfecta (OI) is a genetic disorder of connective tissue. Progressive hearing loss is one of the principal symptoms of OI, affecting about 50% of adult patients. Hearing loss may also occur in childhood and results in additional disability in education and psychosocial adaptation and aggravates the physical handicap. This can be avoided by appropriate otological and audiological treatment. In a nationwide search, 254 Finnish patients with OI were identified indicating a prevalence of 4.9/100 000. Of the 60 children, 45 aged between 4 and 16 years accepting to participate the study on hearing, were evaluated by a questionnaire and clinical audiometry. Hearing loss was defined as pure tone average (PTA_{0.5–2 kHz}) more than 20 dB hearing level (HL). A clinical geneticist determined the type of OI among the 45 patients. Two sporadic OI cases with conductive hearing loss were ascertained (4.4%): An 11-year-old girl with type IV OI with a PTA_{0.5–2 kHz} of 35/40 dB HL and a 15-year-old boy with type IV OI with a PTA_{0.5–2 kHz} of 27/18 dB HL. In addition, a 6-year-old girl with familial OI type I had either a congenital sensorineural deafness or early progressive deafness with PTA_{0.5–2 kHz} of 97/103 dB HL, probably of unrelated aetiology. Conclusion Hearing loss in children with osteogenesis imperfecta is less frequent than generally suspected. Nevertheless, it is recommended that audiometry is performed in children with osteogenesis imperfecta even without symptoms of hearing loss at the age of 10 years, and repeated every 3 years thereafter. Received: 13 October 1999 and in revised forms: 20 December 1999, 13 January 2000 and 24 January 2000 / Accepted: 25 January 2000     

Brain stem evoked response audiometry in neonates

Brain stem evoked response audiometry (BERA) was performed in 50 normal full term newborn infants (25 male, 25 female) to generate normative data base for this age group. The stimuli of 30 dB, 40 dB and 80 dB nHL (normal hearing level) intensities were delivered to each subjects. 30 dB stimulus failed to produce clear wave patterns, whereas upto six vertex positive waves were recognised among which waves I, III and V were commonly present. The absolute latencies of waves I and V at 40 dB nJL were 2.54 +/- 0.21 msec and 7.56 +/- 0.26 msec and at 80 dB nHL these were 2.06 +/- 0.15 msec and 7.09 +/- 0.17 msec respectively. I-V interpeak latencies (IPL) were 5.02 +/- 0.13 msec at 40 dB and 5.03 +/- 0.13 at 80 dB nHL. The latencies of waves I and V were decreased with the increase of intensity of stimuli with the rate of 0.012 msec/dB, bit I-V IPL, i.e., central conduction time remained almost constant. There were no statistically significant differences in the brain stem auditory evoked responses between male and female subjects. Brain stem evoked response audiometry is objective and reliable for hearing screening in neonates.     

Mild impairment of neuro-otological function in early treated congenital hypothyroidism.

Pure tone audiometry, tympanometry, acoustic stapedial reflex thresholds (ASRTs), and auditory evoked brain stem responses (AEBRs) were carried out in 38 children with early treated congenital hypothyroidism aged 10-12 years, together with tests of vestibular function (electronystagraphy, rotational, and caloric tests). Sensorineural hearing loss with thresholds of greater than 15 dB was detected in 18 children (10 at 8 kHz only); only two children had more than 40 dB hearing loss, each in one ear. Raised ASRTs were found in eight children and two children had abnormal AEBRs. Of the 29 children tested, 12 had an abnormality of vestibular function. Although not significant at the 5% level, there was a tendency for the abnormalities to be more prevalent and severe in the children with more severe hypothyroidism, as judged by pretreatment plasma thyroxine. It is concluded that (i) mild abnormality of hearing is still common in children with congenital hypothyroidism despite early treatment but this is much less severe than that found before neonatal screening and (ii) mild abnormalities of vestibular function may be common in early treated congenital hypothyroidism.     

Mild impairment of neuro-otological function in early treated congenital hypothyroidism

Pure tone audiometry, tympanometry, acoustic stapedial reflex thresholds (ASRTs), and auditory evoked brain stem responses (AEBRs) were carried out in 38 children with early treated congenital hypothyroidism aged 10-12 years, together with tests of vestibular function (electronystagraphy, rotational, and caloric tests). Sensorineural hearing loss with thresholds of greater than 15 dB was detected in 18 children (10 at 8 kHz only); only two children had more than 40 dB hearing loss, each in one ear. Raised ASRTs were found in eight children and two children had abnormal AEBRs. Of the 29 children tested, 12 had an abnormality of vestibular function. Although not significant at the 5% level, there was a tendency for the abnormalities to be more prevalent and severe in the children with more severe hypothyroidism, as judged by pretreatment plasma thyroxine. It is concluded that (i) mild abnormality of hearing is still common in children with congenital hypothyroidism despite early treatment but this is much less severe than that found before neonatal screening and (ii) mild abnormalities of vestibular function may be common in early treated congenital hypothyroidism.     

Hearing improvement in patients with Fabry disease treated with agalsidase alfa

AIM: To describe the nature and prevalence of hearing loss in Fabry disease, and its response to enzyme replacement therapy (ERT) with agalsidase alfa. METHODS: Fifteen male patients with Fabry disease were enrolled in a randomized, double-blind study and received placebo (n = 8) or ERT (n = 7) with agalsidase alfa for 6 months. This was followed by an open-label extension of 36 months thus far. Alongside this trial, an additional eight men and two women have so far received open-label ERT for between 6 and 30 months. Pure-tone audiometry, impedance audiometry and otoacoustic emission testing were performed at 0 (baseline), 6, 18, 30 and 42 months. RESULTS: Nine patients (36%) had bilateral and ten (40%) had unilateral high-frequency sensorineural hearing loss (SNHL). Three (12%) had unilateral middle ear effusions with conductive losses persisting beyond 6 months. Only five patients (20%) had normal hearing. The high-frequency SNHL deteriorated over the first 6 months in both placebo and active treatment groups by a median 6.3 dB (p < 0.0001, Wilcoxon matched-pairs). This hearing loss subsequently improved above baseline by 1.5 dB at 18 months (p = 0.07), by 5.0 dB at 30 months (p = 0.006) and by 4.0 dB at 42 months (p = 0.01). CONCLUSION: Significant hearing loss, usually high-frequency SNHL, is a common manifestation of Fabry disease in adults. Alpha-galactosidase A replacement therapy with agalsidase alfa appears to reverse the hearing deterioration in these patients. This improvement, however, is gradual, suggesting the need for long-term ERT.     

Six year effectiveness of a population based two tier infant hearing screening programme.

AIMS: To determine whether a two tier universal infant hearing screening programme (population based risk factor ascertainment and universal distraction testing) lowered median age of diagnosis of bilateral congenital hearing impairment (CHI) >40 dB HL in Victoria, Australia. METHODS: Comparison of whole population birth cohorts pre and post introduction of the Victorian Infant Hearing Screening Program (VIHSP). All babies surviving the neonatal period born in Victoria in 1989 (pre-VIHSP) and 1993 (post-VIHSP) were studied. (1) Pre-1992: distraction test at 7-9 months. (2) Post-1992: infants with risk factors for CHI referred for auditory brain stem evoked response (ABR) assessment; all others screened by modified distraction test at 7-9 months. RESULTS: Of the 1989 cohort (n = 63 454), 1.65/1000 were fitted with hearing aids for CHI by end 1995, compared with 2.09/1000 of the 1993 cohort (n = 64 116) by end 1999. Of these, 79 cases from the 1989 cohort (1.24/1000) and 72 cases from the 1993 cohort (1.12/1000) had CHI >40 dB HL. Median age at diagnosis of CHI >40 dB HL for the 1989 birth cohort was 20.3 months, and for the 1993 cohort was 14.2 months. Median age at diagnosis fell significantly for severe CHI but not for moderate or profound CHI. Significantly more babies with CHI >40 dB HL were diagnosed by 6 months of age in 1993 than in 1989 (21.7% v 6.3%). Compared to the six years pre-VIHSP, numbers aided by six months were consistently higher in the six years post-VIHSP (1.05 per 100 000 births versus 13.4 per 100 000 births per year). CONCLUSIONS: VIHSP resulted in very early diagnosis for more infants and lowered median age of diagnosis of severe CHI. However, overall results were disappointing.     

Preschool hearing screening: Evaluation of a parental questionnaire

Objective: To evaluate the validity of a parental questionnaire used to screen preschool children for persistent hearing impairment.
Methodology: Six-hundred and eighty-five children aged 4–5 years from a Metropolitan area of Adelaide, Australia, were enrolled. Each parent completed a questionnaire aimed at detecting parental concerns about hearing impairment. Screening audiometry was then performed. Children who failed the initial audiometry screening underwent repeat audiometry screening 6–8 weeks later. The audiometry and questionnaire data were then compared.
Results: Of the 657 children who successfully completed initial audiometry, 544 (83%) passed and 113 (17%) failed. Of the 84 children who had follow-up audiometry, 64 (76%) passed. Parental concerns were identified on questionnaire in 50% of all children. Neither individual questions nor the number of concerns were found to relate to audiometry results. Compared with audiometry results, the hearing screening questionnaire had a sensitivity of 56% and specificity of 52%.
Conclusions: The hearing questionnaire used in this study and in several Australian states is an ineffective screening test for detecting persistent hearing loss.     

Six year effectiveness of a population based two tier infant hearing screening programme

Aims: To determine whether a two tier universal infant hearing screening programme (population based risk factor ascertainment and universal distraction testing) lowered median age of diagnosis of bilateral congenital hearing impairment (CHI) >40 dB HL in Victoria, Australia. Methods: Comparison of whole population birth cohorts pre and post introduction of the Victorian Infant Hearing Screening Program (VIHSP). All babies surviving the neonatal period born in Victoria in 1989 (pre-VIHSP) and 1993 (post-VIHSP) were studied. (1) Pre-1992: distraction test at 7–9 months. (2) Post-1992: infants with risk factors for CHI referred for auditory brain stem evoked response (ABR) assessment; all others screened by modified distraction test at 7–9 months. Results: Of the 1989 cohort (n = 63 454), 1.65/1000 were fitted with hearing aids for CHI by end 1995, compared with 2.09/1000 of the 1993 cohort (n = 64 116) by end 1999. Of these, 79 cases from the 1989 cohort (1.24/1000) and 72 cases from the 1993 cohort (1.12/1000) had CHI >40 dB HL. Median age at diagnosis of CHI >40 dB HL for the 1989 birth cohort was 20.3 months, and for the 1993 cohort was 14.2 months. Median age at diagnosis fell significantly for severe CHI but not for moderate or profound CHI. Significantly more babies with CHI >40 dB HL were diagnosed by 6 months of age in 1993 than in 1989 (21.7% v 6.3%). Compared to the six years pre-VIHSP, numbers aided by six months were consistently higher in the six years post-VIHSP (1.05 per 100 000 births versus 13.4 per 100 000 births per year). Conclusions: VIHSP resulted in very early diagnosis for more infants and lowered median age of diagnosis of severe CHI. However, overall results were disappointing.     

Hearing assessment by brainstem auditory evoked responses (BAER) in neonates at risk.

In the present study, brainstorm auditory evoked responses (BAER) were recorded in 68 at risk neonates discharged from the neonatal ICU of Safdarjung Hospital. The high risk group of 35 neonates included 13 neonates with multiple (3-4) risk factors and 22 neonates with single risk factors, viz., prematurity (less than 32 weeks) low birth weight (LBW) (less than 1500 g), hyperbilirubinemia requiring exchange transfusion, severe birth asphyxia, craniofacial malformations and sepsis with meningitis treated with amikacin for 3 weeks. The remaining 33 neonates were grouped in the low risk category who had only one of the following factors: prematurity (33-36 weeks)/LBW (1500-2000 g), hyperbilirubinemia requiring phototherapy, mild/moderate birth asphyxia, or sepsis treated with amikacin for 2 weeks. The test was performed at the mean conceptional age of 40.2 weeks (range 34-44 weeks) and involved determination of threshold of hearing as per presence of wave V. A normal response had wave V at 30 dB hearing level click stimulus at 50/sec from both ears or to 30 dB hearing level from one ear and 45 dB hearing level from the other ear. Thirteen neonates of the high risk group failed to produce a normal response (5 failed at 30 dB, 6 failed at 45 dB, and 2 failed at 75 dB hearing level). Forty six per cent of them had multiple high risk factors. All the low risk group neonates had normal threshold of 30 dB hearing level in the initial screening.(ABSTRACT TRUNCATED AT 250 WORDS)     

Hearing improvement in patients with Fabry disease treated with agalsidase alfa

Aim : To describe the nature and prevalence of hearing loss in Fabry disease, and its response to enzyme replacement therapy (ERT) with agalsidase alfa. Methods : Fifteen male patients with Fabry disease were enrolled in a randomized, double-blind study and received placebo ( n = 8) or ERT ( n = 7) with agalsidase alfa for 6 months. This was followed by an open-label extension of 36 months thus far. Alongside this trial, an additional eight men and two women have so far received open-label ERT for between 6 and 30 months. Pure-tone audiometry, impedance audio-metry and otoacoustic emission testing were performed at 0 (baseline), 6, 18, 30 and 42 months. Results : Nine patients (36%) had bilateral and ten (40%) had unilateral high-frequency sensorineural hearing loss (SNHL). Three (12%) had unilateral middle ear effusions with conductive losses persisting beyond 6 months. Only five patients (20%) had normal hearing. The high-frequency SNHL deteriorated over the first 6 months in both placebo and active treatment groups by a median 6.3 dB ( p < 0.0001, Wilcoxon matched-pairs). This hearing loss subsequently improved above baseline by 1.5 dB at 18 months (p = 0.07), by 5.0 dB at 30 months ( p = 0.006) and by 4.0 dB at 42 months ( p = 0.01).
Conclusion : Significant hearing loss, usually high-frequency SNHL, is a common manifestation of Fabry disease in adults. α-Galactosidase A replacement therapy with agalsidase alfa appears to reverse the hearing deterioration in these patients. This improvement, however, is gradual, suggesting the need for long-term ERT.     

Auditory Function after Continuous Infusion of Gentamicin to High-risk Newborns

ABSTRACT. Audiometry was performed at four years of age in 69 of 105 surviving children who had received continuous intravenous infusion of gentamicin during neonatal intensive care. A hearing loss of 20 dB was found in 2 of them (3 %), corresponding to that shown in other studies of survivors following neonatal intensive care. Free field audiometry performed in another 7 children and questionnaires returned from 13 of the remaining 29 gave no suspicion of hearing loss. Thus there is no indication that continuous 24 hours intravenous infusion of gentamicin causes more hearing impairment than intermittent intravenous or intramuscular administration.     

Auditory function after continuous infusion of gentamicin to high-risk newborns

Audiometry was performed at four years of age in 69 of 105 surviving children who had received continuous intravenous infusion of gentamicin during neonatal intensive care. A hearing loss of 20 dB was found in 2 of them (3%), corresponding to that shown in other studies of survivors following neonatal intensive care. Free field audiometry performed in another 7 children and questionnaires returned from 13 of the remaining 29 gave no suspicion of hearing loss. Thus there is no indication that continuous 24 hours intravenous infusion of gentamicin causes more hearing impairment than intermittent intravenous or intramuscular administration.     

Prevalence of Childhood Hearing Loss and Secular Trends: A Systematic Review and Meta-Analysis

BackgroundBetter epidemiologic information on childhood hearing loss would inform research priorities and efforts to prevent its progression.ObjectivesTo estimate prevalence and secular trends in children's hearing loss.Data SourcesWe searched MEDLINE and Embase from January 1996 to August 2017.Study Eligibility CriteriaWe included epidemiologic studies in English reporting hearing loss prevalence.Study Appraisal and Synthesis MethodsThe modified Leboeuf-Yde and Lauritsen tool was used to assess methodological quality. Meta-analyses combined study-specific estimates using random-effects models.ParticipantsChildren 0 to 18 years of age.ResultsAmong 88 eligible studies, 43.2% included audiometric measurement of speech frequencies. In meta-analyses, pooled prevalence estimates of slight or worse bilateral speech frequency losses >15 decibels hearing level (dB HL) were 13.1% (95% confidence interval [CI], 10.0–17.0). Using progressively more stringent cutpoints, pooled prevalence estimates were 8.1% (95% CI, 1.3–19.8) with >20 dB HL, 2.2% (95% CI, 1.4–3.0) with >25 dB HL, 1.8% (95% CI, 0.4–4.1) with >30 dB HL, and 0.9% (95% CI, 0.1–2.6) with >40 dB HL. Also, 8.9% (95% CI, 6.4–12.3) had likely sensorineural losses >15 dB HL in 1 or both ears, and 1.2% (95% CI, 0.5–2.1) had self-reported hearing loss. From 1990 to 2010, the prevalence of losses >15 dB HL in 1 or both ears rose substantially (all P for trend <.001).LimitationsThe studies had high heterogeneity and offered limited information for hearing loss types and secular trend.Conclusions and ImplicationsChildhood slight or worse hearing loss is prevalent and may be increasing. Advances in understanding hearing loss trajectories, causes, and prevention would require international repositories and longitudinal studies with audiometric data beginning in childhood.Systematic Review Registration NumberPROSPERO 2016 CRD42016034148.     

NICU高危新生儿早期的听力研究

目的　探讨新生儿重症监护室 (NICU)中重症患儿及高危儿与听力障碍或丧失相关的危险因素及其发病率。方法　对 1999年 12月～ 2 0 0 1年 8月 ,入住我院NICU的 2 4 8例听力障碍高危儿 ,在病情稳定后或出院前用听性脑干反应进行听力评价。结果　全部受检患儿中有 72例呈阳性结果 ,该组新生儿初次检查听力异常的发生率为 2 9 0 3% ,其中 3例系重度以上听力障碍。听力障碍的发生率在窒息组为 4 0 0 0 % ;高胆红素血症组为 2 6 37% ;早产儿组为 34 0 9% ,出生体重 <15 0 0g者阳性率尤高 ;接受机械通气组为 4 0 0 0 % ;应用耳毒性药物组为 4 1 30 %。结论　在NICU住院的新生儿中 ,存在较多与听力障碍有关的高危因素 ,该组新生儿听力障碍的发生率较正常活产新生儿明显增高。所以 ,高危新生儿从NICU出院前应常规进行听力检查。     

Parental suspicion of hearing loss in children with otitis media with effusion

Objective This study aimed to evaluate the parental suspicion of hearing loss in children with otitis media with effusion (OME). As part of a population-based survey in a screening programme among 6- to 7-year-old Chinese children in Hong Kong, OME cases and controls were studied for the value of parental observations in the prediction of OME and hearing test results.Subjects and methods Prior to the otoscopic and tympanometric examination of the children on school premises, a self-administered binary-choice question was sent to the parents asking whether there was any suspicion of hearing impairment. Positive screens and randomly selected negative screens were seen in a hospital clinic for the confirmation of case and control status 2 to 3 weeks after the school screening. Aural examination under microscopy, repeated tympanometry and stapedial reflex testing, and pure-tone audiometry (PTA) were conducted, and 117 cases and 159 controls were included in this study.Results The average PTA conductive threshold levels in the individual children with OME ranged from 3.8 dB to 40.0 dB with a group mean of 17.0 dB in the better-hearing ears. Parental suspicion of hearing deficit was significantly associated with OME (p<0.001) but not PTA findings (p=0.686). The sensitivity of parent-suspected hearing impairment to detect OME however was very low (19.7%).Discussion In other words, if we had relied on parental suspicion as the first screening, at least 80% of the OME cases would have been missed. We conclude that the parental suspicion of hearing loss is inadequate for the identification of mild hearing loss as caused by OME. Health education is recommended to improve parental awareness of the disease.     

Rezeptiver Wortschatzumfang bilateral schallempfindungsgestörter Kinder im Verlauf

Objective

The aim of this study was to assess receptive vocabulary development in children with aided residual hearing, but without major co-morbidities.

Patients and Methods

A total of 26 boys and 27 girls (t1: 2.0–7.4 years old) with bilateral sensorineural hearing loss (average at frequencies of 0.5, 1, 2, 4 kHz >21 dB in the better hearing ear) were recruited out of the 1994 implemented Göttinger Hör-Sprachregister (Gö HSR). The mean age at diagnosis was 51.4 months (SD 19.6; min. 14; max. 85), the mean hearing aiding age: 51.9 months (SD 19.6). The children had an average nonverbal intelligence in Raven’s Coloured Progressive Matrices and in CMMS respectively. The individual assessment of receptive vocabulary was carried out at three time points using standardized test measures. The raw test scores were converted to T-scores (M=50; SD=10; normed for hearing children). The first psychometric examination took place after the ascertainment of the hearing loss (t1). Two follow-ups (t2, t3) were performed at 6–9 month time intervals.

Results

No child with a hearing loss >61 dB HL obtained an age appropriate receptive vocabulary score. On average, the study group exhibited an age-delayed lexical performance at t1 (M=38.7; SD=14.7) which significantly improved over time reaching the lower norm level at t3 (M=44.7; SD=18.0; p<0.001). The number of children with below norm performance did not change (t1=53%, t3=47%). The mildly hearing impaired children (21–40 dB) exhibited an age adequate receptive test score at t1 (except for three children). These three children with delayed results scored normally by t3. The children with moderate hearing loss (41–70 dB) improved significantly (t1–t3; p<0.001). The mean vocabulary performance of severe, bilaterally impaired children (>70 dB HL) did not increase.

Conclusion

Even a hearing loss <40 dB may negatively affect receptive vocabulary development. Receptive vocabulary outcome was not highly variable.     

听觉脑干反应和耳声发射在高危儿听力筛查中的应用

目的：耳声发射(OAE)和听觉脑干反应(ABR) 是新生儿听力筛查的常用方法。该研究旨在探讨畸变产物耳声发射(DPOAE) 和ABR应用于重症监护病房(NICU)高危新生儿听力筛查的差异和意义。方法：分别应用Smart-EP型听觉脑干诱发电位仪和Smart-OAE畸变产物耳声发射检查仪对600例(1 200耳)不同病因所致的高危儿同时进行DPOAE和ABR检查,将两种方法取得的检测结果进行比较。结果：在600例(1 200耳)高危新生儿中,ABR的异常率(78.6%,943/1 200耳)远高于DPOAE的未通过率(22.3%,268/1 200耳);二种检查的共同阴/阳性率分别为20.8%(241/1 200耳)和21%(252/1 200耳)。1 200耳中有493耳DPOAE和ABR的测试结果一致,占41.1%;707耳的测试结果不一致,占58.9%。DPOAE测试的假阳性率为6.0%(16/268耳),假阴性率为74.1%(691/932耳)。结论： DPOAE仅反映耳蜗功能,单独用于高危新生儿听功能筛查的价值有限。ABR检查果相对可靠,NICU高危新生儿听力筛查应先做ABR检查,ABR异常者再做OAE检查。ABR和OAE二种检测方法相互结合,方能提高高危新生儿听力筛查的准确性。     

Brainstem acoustic evoked potentials in children with developmental disabilities--a useful tool for differential diagnosis

In a retrospective study brainstem acoustic evoked potentials (BAEP) were evaluated in 222 children with psychomotor retardation or dysmorphic signs. Registrations were done, when no clear response to acoustic stimuli of medium intensity (60-80 dBA) could be obtained during clinical examination. Only 118 children (53%) had normal BAEP. 50 patients (22%) suffered from hearing impairment. 39 children (17%) showed disturbances of neuronal conduction. In 15 cases (7%) a combination of both conditions occurred. The mean age of our children with hearing impairment was 33.1 months, no case having been diagnosed before. In 57% the impairment was of the conductive type with an amount of less than 40 dB nHL This type was predominant in children with skeletal dysplasias (43%), chromosomal aberrations (43%) and malformation syndromes (40%). Severe hearing deficits of the sensorineural type with more than 69 dB nHL were found in children with malformation syndromes (28%), perinatal injuries (23%) and cns malformations (16%). As far as reference data were available, the hearing impairment in the BAEP was confirmed in 92% by our pedaudiologists. As a consequence hearing aids were first prescribed in 10 children, their medium age being 33.6 months. In 18 cases grommets were inserted. 9 children required paracentesis and 4 adenotomy. Disturbances of neuronal conduction with increased interpeak latencies and deformed potentials were predominantly found in the group of children with neurometabolic diseases (67%) and cns malformations (32%). Early diagnosis of hearing impairment in children with psychomotor retardation remains a problem as it is in the general population. More attention in clinical examination and appropriate screening is necessary. BAEP provide a powerful tool for hearing screening and additional information for differential diagnosis especially in children with neurometabolic diseases.     

Auditory and vestibular findings in Fabry disease: a study of hemizygous males and heterozygous females

AIM: This study aimed to evaluate audiological and vestibular involvement in Fabry disease and the early effects of enzyme replacement therapy with human alpha-galactosidase A. METHODS: Fourteen patients (10 males, 4 females) aged 14-57 years were studied. Each patient underwent a clinical (history of otological and vestibular aspects, otoscopy) and instrumental (pure tone and speech audiometry, impedance, auditory brainstem response and oto-acoustic emission recordings, vestibular caloric tests, electronystagmography during acceleratory stimulation, dynamic posturography) evaluation before starting enzyme replacement therapy. RESULTS: Fifty per cent of patients complained of hearing symptoms (hearing loss, tinnitus, ear fullness). Subjective hearing loss was present in six cases and in three cases it was the first reported symptom of Fabry disease. In six of the seven cases the onset and/or progression of hearing symptoms were sudden. Vertigo or dizziness was reported by four patients and in two cases was associated with hearing symptoms. Audiological evaluation showed sensorineural hearing loss in eight patients (5 males, 3 females). Hearing loss was unilateral in six cases and bilateral in the remaining two cases. The hearing loss (HL) ranged from 30 to 80 dB HL (mean, 43 dB HL) and the lesion was always cochlear. Vestibular examination showed abnormalities in four patients (bilateral weak/abolished response in three cases, side prevalence in one case), which were not related to either the audiological results or the history of vertigo/dizziness. CONCLUSION: Involvement of the inner ear is common in men and women with Fabry disease. We found a high incidence of cochlear hearing loss, which was typically unilateral and showed onset and/or progression by sudden episodes. Vascular or hydropic mechanisms could be hypothesized to explain audiological findings. Vestibular involvement had a lower incidence and showed a different pattern, thus suggesting that several pathophysiological mechanisms could play a role in determining inner ear damage in Fabry disease. Our preliminary results show that enzyme replacement therapy may stabilize hearing function; however, further follow-up is required.     

Otoacoustic emissions as a screening test for hearing impairment in children recovering from acute bacterial meningitis

OBJECTIVES: To study the efficacy of otoacoustic emissions (OAEs) as a screening test for hearing impairment in children with acute bacterial meningitis. Hearing tests were performed before discharge from the hospital in an attempt to improve coverage and avoid delays in the diagnosis of postmeningitic hearing loss. METHODS: Children with bacterial meningitis were recruited from 21 centers. In the 48 hours before discharge from the hospital, all patients underwent a thorough audiologic assessment consisting of transient evoked OAEs, auditory brainstem responses (ABRs), otoscopy, and tympanometry. Hearing loss was defined as ABR threshold >/=30 dB. The results of OAE screening were compared with the gold standard of ABR threshold. RESULTS: Of 124 children recruited, we were able to perform both OAEs and ABRs on 110 children. Seven (6.3%) of the 110 children had ABR threshold >/=30 dB; 2 had sensorineural hearing loss and 5 had conductive hearing loss. At follow-up, hearing loss persisted in both cases of sensorineural hearing loss and no new cases were identified. All 7 children with hearing loss failed the OAE screening test. Ninety-four children with normal hearing thresholds passed the test, and 9 failed. Thus, the screening test had a sensitivity of 1.00 (95% confidence interval, 0.59 to 1.00), a specificity of 0.91 (0.85 to 0.97), a positive predictive value of 0. 44 (0.20 to 0.70), and a negative predictive value of 1.00 (0.96 to 1.00). CONCLUSIONS: OAE screening in children recovering from meningitis was found to be feasible and effective. The test was highly sensitive and reasonably specific. Inpatient OAE screening should allow early diagnosis of postmeningitic hearing loss and prompt auditory rehabilitation.