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Objectives: Neonatal hearing impairment is a common disorder with a prevalence of 1 to 2‰ worldwide, with significant consequences on overall development when rehabilitated too late. New-born hearing screening has been implemented in the 1990s in most European countries and the USA. The Upper-Normandy region of France has been conducting a pilot program since 1999. The aim of this prospective study was to evaluate and critically analyse it., Methods: The Upper-Normandy universal new-born hearing screening program is performed in two steps. Between 1999 and 2004, first, we administered a Transient Evoked Oto Acoustic Emission (TEOAE) test was administered a few days after birth for healthy newborns without risk factors. For newborns admitted to a neonatal intensive care unit (NICU) or presenting risk factors, was administered an automated auditory brainstem response (AABR) test prior to discharge. Second, newborns who failed the initial hearing screening were retested as outpatients using TEOAE. Since 2004, infants who failed the initial screen were tested with AABR 3 to 4 weeks later as outpatients, providing an opportunity to compare the two protocols., Results: Overall screening coverage in the Upper-Normandy region is 99.8%. First step coverage is 99.58% in well-infant nurseries and 97.09% in the NICU. The test-retest procedure during the first step and the use of AABR for the second resulted in higher follow-up rates and lower false positive rates., Conclusions: The Upper-Normandy region universal newborn hearing screening program facilitated diagnosis and rehabilitation of infants before age of 9 months, most notably when severe to profound hearing impairment was found., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Objectives: To determine the diagnostic approach to severe or profound bilateral postmeningitic deafness and to propose management guidelines., Material and Methods: A retrospective review of five patients (two adolescents and three infants) with rapidly progressive severe bilateral deafness following an episode of meningitis managed between 2004 and 2010., Results: The two adolescents presented Neisseria meningitidis meningitis and the three infants presented Streptococcus pneumoniae meningitis. Acquired bilateral deafness was diagnosed by audiometry an average of 68.8 days (range: 9-210) after the episode of meningitis. Behavioural audiological testing, adapted to age and state of health, was performed in all patients. Deafness was confirmed by Auditory Brainstem Response tests. All five patients were assessed by computed tomography (CT) and magnetic resonance imaging (MRI) within ten days. T2-weighted MRI sequences showed endolymph changes in four patients. CT scan demonstrated ossification in only one patient. Bilateral cochlear implant was performed in all patients, with complete electrode array insertion for eight implants and partial insertion for two implants (20 and 21 out of 22 electrodes inserted). Good results were obtained with cochlear implants in four cases., Conclusions: Bilateral deafness can occur immediately or several months after bacterial meningitis, regardless of the micro-organism responsible, justifying screening by behavioural audiological testing adapted to age for two years following bacterial meningitis. Auditory Brainstem Response testing can confirm audiometric findings. When severe or profound bilateral deafness is observed, MRI must be performed urgently to detect endolymph inflammation or ossification. Early bilateral cochlear implantation is recommended in the presence of ossification., (Copyright © 2014 Elsevier Masson SAS. All rights reserved.)

Background: Usher syndrome (USH) combines sensorineural deafness with blindness. It is inherited in an autosomal recessive mode. Early diagnosis is critical for adapted educational and patient management choices, and for genetic counseling. To date, nine causative genes have been identified for the three clinical subtypes (USH1, USH2 and USH3). Current diagnostic strategies make use of a genotyping microarray that is based on the previously reported mutations. The purpose of this study was to design a more accurate molecular diagnosis tool., Methods: We sequenced the 366 coding exons and flanking regions of the nine known USH genes, in 54 USH patients (27 USH1, 21 USH2 and 6 USH3)., Results: Biallelic mutations were detected in 39 patients (72%) and monoallelic mutations in an additional 10 patients (18.5%). In addition to biallelic mutations in one of the USH genes, presumably pathogenic mutations in another USH gene were detected in seven patients (13%), and another patient carried monoallelic mutations in three different USH genes. Notably, none of the USH3 patients carried detectable mutations in the only known USH3 gene, whereas they all carried mutations in USH2 genes. Most importantly, the currently used microarray would have detected only 30 of the 81 different mutations that we found, of which 39 (48%) were novel., Conclusions: Based on these results, complete exon sequencing of the currently known USH genes stands as a definite improvement for molecular diagnosis of this disease, which is of utmost importance in the perspective of gene therapy.

Objective: To investigate the implication of SLC26A4, FOXI and KCNJ10 genes in unilateral hearing impairment associated with ipsilateral inner ear malformation (Enlargement of the vestibular aqueduct and/or Mondini dysplasia)., Methods: We have gathered 25 patients presenting unilateral hearing impairment and ipsilateral enlarged vestibular aqueduct. For each of the patients, we have analyzed SLC26A4, FOXI1 and KCNJ10 genes sequences., Results: The analysis of SLC26A4 revealed only eight heterozygous SLC26A4 sequence variants, three of them being novel (p.Met147Ile, p.Asn538Asn and p.Leu627Arg). None of the patients carried a second mutation on the other allele. Moreover, the SLC26A4 locus was excluded by segregation analysis in two families. No mutations were present in FOXI1 and KCNJ10 genes., Conclusions: Together, these data suggest that SLC26A4, FOXI1 and KCNJ10 are not major determinants in unilateral deafness and enlarged vestibular aqueduct compared with their implication in Pendred syndrome and non-syndromic bilateral enlarged vestibular aqueduct., (Copyright 2010 Elsevier Ireland Ltd. All rights reserved.)

Mitochondrial DNA (mtDNA) mutations have been implicated in non-syndromic hearing loss either as primary or as predisposing factors. As only a part of the mitochondrial genome is usually explored in deafness, its prevalence is probably under-estimated. Among 1350 families with non-syndromic sensorineural hearing loss collected through a French collaborative network, we selected 29 large families with a clear maternal lineage and screened them for known mtDNA mutations in 12S rRNA, tRNASer(UCN) and tRNALeu(UUR) genes. When no mutation could be identified, a whole mitochondrial genome screening was performed, using a microarray resequencing chip: the MitoChip version 2.0 developed by Affymetrix Inc. Known mtDNA mutations was found in nine of the 29 families, which are described in the article: five with A1555G, two with the T7511C, one with 7472insC and one with A3243G mutation. In the remaining 20 families, the resequencing Mitochip detected 258 mitochondrial homoplasmic variants and 107 potentially heteroplasmic variants. Controls were made by direct sequencing on selected fragments and showed a high sensibility of the MitoChip but a low specificity, especially for heteroplasmic variations. An original analysis on the basis of species conservation, frequency and phylogenetic investigation was performed to select the more probably pathogenic variants. The entire genome analysis allowed us to identify five additional families with a putatively pathogenic mitochondrial variant: T669C, C1537T, G8078A, G12236A and G15077A. These results indicate that the new MitoChip platform is a rapid and valuable tool for identification of new mtDNA mutations in deafness.

Sensorineural hearing loss is the most frequent sensory deficit of childhood and is of genetic origin in up to 75% of cases. It has been shown that mutations of the SLC26A4 (PDS) gene were involved in syndromic deafness characterized by congenital sensorineural hearing impairment and goitre (Pendred's syndrome), as well as in congenital isolated deafness (DFNB4). While the prevalence of SLC26A4 mutations in Pendred's syndrome is clearly established, it remains to be studied in large cohorts of patients with nonsyndromic deafness and detailed clinical informations. In this report, 109 patients from 100 unrelated families, aged from 1 to 32 years (median age: 10 years), with nonsyndromic deafness and enlarged vestibular aqueduct, were genotyped for SLC26A4 using DHPLC molecular screening and sequencing. In all, 91 allelic variants were observed in 100 unrelated families, of which 19 have never been reported. The prevalence of SLC26A4 mutations was 40% (40/100), with biallelic mutation in 24% (24/100), while six families were homozygous. All patients included in this series had documented deafness, associated with EVA and without any evidence of syndromic disease. Among patients with SLC26A4 biallelic mutations, deafness was more severe, fluctuated more than in patients with no mutation. In conclusion, the incidence of SLC26A4 mutations is high in patients with isolated deafness and enlarged vestibular aqueduct and could represent up to 4% of nonsyndromic hearing impairment. SLC26A4 could be the second most frequent gene implicated in nonsyndromic deafness after GJB2, in this Caucasian population.

Objectives: The aim of this study was to evaluate Universal Screening using transient evoked otoacoustic emisions (TEOAE) in the geographical Department of Eure -France., Material and Methods: This hearing screening was initially developed at a single maternity ward (September 1999 to December 2002), and then throughout the Department (January 2003 to December 2003). One or two successive TEOAE tests were recorded. In cases of a positive test, a new TEAO was recorded at otolaryngology consultation one month later. If this test was again positive, a new consultation with brainstem auditory evoked potential (BAEP) was scheduled. If hearing loss was suspected following BAEP, an audiometric test was performed., Results: A total of 10,770 newborns were screened (99.38%), 65 newborns were lost to follow-up (0.59%), 18 bilateral hearing losses were identified (1.6/1000), and 5 of them had hearing loss risk factors., Conclusion: This study demonstrated that a hearing screening program in the maternity ward using TEOAE is recommended and provides optimal results.

Objectives: To analyze the clinical features of hearing impairment and to search for correlations with the genotype in patients with DFNB1., Design: Case series., Setting: Collaborative study in referral centers, institutional practice. Patients A total of 256 hearing-impaired patients selected on the basis of the presence of biallelic mutations in GJB2 or the association of 1 GJB2 mutation with the GJB6 deletion (GJB6-D13S1830)del., Main Outcome Measures: The prevalence of GJB2 mutations and the GJB6 deletion and audiometric phenotypes related to the most frequent genotypes., Results: Twenty-nine different GJB2 mutations were identified. Allelic frequency of 35delG was 69%, and the other common mutations, 313del14, E47X, Q57X, and L90P, accounted for 2.6% to 2.9% of the variants. Concerning GJB6, (GJB6-D13S1830)del accounted for 5% of all mutated alleles and was observed in 25 of 93 compound heterozygous patients. Three novel GJB2 mutations, 355del9, V95M, and 573delCA, were identified. Hearing impairment was frequently less severe in compound heterozygotes 35delG/L90P and 35delG/N206S than in 35delG homozygotes. Moderate or mild hearing impairment was more frequent in patients with 1 or 2 noninactivating mutations than in patients with 2 inactivating mutations. Of 93 patients, hearing loss was stable in 73, progressive in 21, and fluctuant in 2. Progressive hearing loss was more frequent in patients with 1 or 2 noninactivating mutations than in those with 2 inactivating mutations. In 49 families, hearing loss was compared between siblings with similar genotypes, and variability in terms of severity was found in 18 families (37%)., Conclusion: Genotype may affect deafness severity, but environmental and other genetic factors may also modulate the severity and evolution of GJB2-GJB6 deafness.

Recent investigations identified a large deletion of the GJB6 gene in trans to a mutation of GJB2 in deaf patients. We looked for GJB2 mutations and GJB6 deletions in 255 French patients presenting with a phenotype compatible with DFNB1. 32% of the patients had biallelic GJB2 mutations and 6% were a heterozygous for a GJB2 mutation and a GJB6 deletion. Biallelic GJB2 mutations and combined GJB2/GJB6 anomalies were more frequent in profoundly deaf children. Based on these results, we are now assessing GJB6 deletion status in cases of prelingual hearing loss., (Copyright 2004 Wiley-Liss, Inc.)

Mutations in GJB2 are the most common cause of congenital nonsyndromic hearing loss. The controversial allele variant M34T has been hypothesized to cause autosomal dominant or recessive nonsyndromic hearing impairment and some in vitro data has been consistent with this hypothesis. In this report, we present the clinical and genotypic study of 11 families (seven familial forms of nonsyndromic sensorineural hearing loss (NSSNHL) and four sporadic cases) in which the M34T GJB2 variant has been identified. The M34T mutation did not segregate with the deafness in six of the seven familial forms of NSSNH. Eight persons with normal audiogram presented a heterozygous M34T variation and five normal hearing individuals were composite heterozygous for M34T and another GJB2 mutation. Four normal hearing individuals with a documented audiogram were M34T/35delG and one was M34T/(GJB6-D13S1830)del. Screening a French control population of 116 subjects we have found an M34T allele frequency of 1.72%. This percentage was not significatively different from the prevalence of the M34T allele in the deaf population, which was 2.12%. All these data suggest that the M34T variant is not clinically significant in human and is a frequent polymorphism in France.

A retrospective study of 72 children with a profound (average hearing loss > 90 dB) unilateral sensorineural hearing loss (PUSNHL) was carried out in the ENT department at the Rouen hospital in 1988 and 1994. This study intended to investigate the etiologies, how it was recognized, the age of the onset and the results of the medical evaluation of these PUSNHL. We found, in 2 cases, that vestibular lesions of the healthy ear were present before the onset of a hearing loss on this side, turning the PUSNHL into a bilateral deafness. We tried to correlate the etiologies, age of onset of the PUSNHL, status of the opposite ear and possible scholar problems in the group of the 42 children followed-up for more than 2 years (mean follow-up time = 7 years). Among children suffering from PUSNHL, we specified a group with higher risk of school failures, allowing ENT physicians to propose more accurate management to these children.