Etiology of early hearing loss in Brazilian children.

INTRODUCTION: Hearing loss etiology depends on the population studied as well as on the ethnicity and the socio-economic condition of the analyzed region. Etiological diagnosis contributes to the improvement of preventive measures and to the early identification of this deficiency. OBJECTIVE: To identify the etiological factors of hearing loss and its prevalence in a tertiary hospital in southern Brazil, to verify the frequency of mutations in GJB2 and GJB6 genes, and to correlate the degree of hearing loss with the etiological factors of deafness. METHODS: This prevalence study involved 140 children with bilateral sensorineural or mixed hearing loss. Medical history, physical examination, audiometry, and evoked auditory brainstem response were conducted. Imaging and genetic examinations were also performed. RESULTS: Etiologies and their prevalence were as follows: (a) indeterminate causes, 31.4%; (b) conditions related to neonatal period, 22.1%; (c) genetic, 22.1%; (d) auditory neuropathy, 10%; (e) other factors (cortical malformation, intracranial hemorrhage, and internal ear malformations), 7.9% and (f) congenital infections, 6.4%. Within the genetic cases, ten homozygous and seven heterozygotes of the 35delG mutation were identified, besides two cases of rare variants of GJB2: p.Try172* and p.Arg184Pro. One case with homozygosis of del(GJB6-D13S1830) was found. Regarding severity of hearing loss, in 78.6% of the cases the degree of hearing loss was profound and there were no significant differences when comparing between etiologies. CONCLUSION: The number of indeterminate etiologies is still high and congenital CMV infection may be a possible cause of undiagnosed etiology for hearing loss. The predominance of etiologies related to neonatal conditions and infectious causes are characteristic of developing countries. The most prevalent mutation was 35delG, the main GJB2 gene, probably because of the European influence in the genotype of our population.

Etiology of early hearing loss in Brazilian children / Etiologia da perda auditiva precoce em crianças brasileiras

Abstract Introduction Hearing loss etiology depends on the population studied as well as on the ethnicity and the socio-economic condition of the analyzed region. Etiological diagnosis contributes to the improvement of preventive measures and to the early identification of this deficiency. Objective To identify the etiological factors of hearing loss and its prevalence in a tertiary hospital in southern Brazil, to verify the frequency of mutations in GJB2 and GJB6 genes, and to correlate the degree of hearing loss with the etiological factors of deafness. Methods This prevalence study involved 140 children with bilateral sensorineural or mixed hearing loss. Medical history, physical examination, audiometry, and evoked auditory brainstem response were conducted. Imaging and genetic examinations were also performed. Results Etiologies and their prevalence were as follows: (a) indeterminate causes, 31.4%; (b) conditions related to neonatal period, 22.1%; (c) genetic, 22.1%; (d) auditory neuropathy, 10%; (e) other factors (cortical malformation, intracranial hemorrhage, and internal ear malformations), 7.9% and (f) congenital infections, 6.4%. Within the genetic cases, ten homozygous and seven heterozygotes of the 35delG mutation were identified, besides two cases of rare variants of GJB2: p.Try172* and p.Arg184Pro. One case with homozygosis of del(GJB6-D13S1830) was found. Regarding severity of hearing loss, in 78.6% of the cases the degree of hearing loss was profound and there were no significant differences when comparing between etiologies. Conclusion The number of indeterminate etiologies is still high and congenital CMV infection may be a possible cause of undiagnosed etiology for hearing loss. The predominance of etiologies related to neonatal conditions and infectious causes are characteristic of developing countries. The most prevalent mutation was 35delG, the main GJB2 gene, probably because of the European influence in the genotype of our population.

Resumo Introdução A etiologia da perda auditiva depende da população estudada, da etnia e da condição socioeconômica da região analisada. O diagnóstico etiológico contribui para o aprimoramento das medidas preventivas e para a identificação precoce dessa deficiência. Objetivos Identificar os fatores etiológicos da perda auditiva e sua prevalência em um hospital terciário do sul do Brasil, verificar a frequência de mutações nos genes GJB2 e GJB6 e correlacionar o grau da perda auditiva com os fatores etiológicos da deficiência auditiva. Método Este estudo de prevalência avaliou 140 crianças com perda auditiva neurossensorial bilateral ou mista. Foram submetidos a anamnese com histórico médico, exame físico, audiometria e potencial evocado auditivo de tronco encefálico. Exames de imagem e genéticos também foram feitos. Resultados As etiologias e sua prevalência foram as seguintes: (a) causas indeterminadas, 31,4%; (b) condições relacionadas ao período neonatal, 22,1%; (c) genética, 22,1%; (d) neuropatia auditiva, 10%; (e) outros fatores (malformação cortical, hemorragia intracraniana e malformações da orelha interna), 7,9% e (f) infecções congênitas, 6,4%. Entre os casos genéticos, foram identificados dez casos homozigotos e sete heterozigotos da mutação 35delG, além de dois casos de variantes raras do GJB2: p.Try172* e p.Arg184Pro. Foi encontrado um caso homozigoto da mutação del (GJB6‐D13S1830). Em relação à gravidade da perda auditiva, em 78,6% dos casos o grau da perda auditiva foi profundo e não houve diferenças significantes na comparação entre as etiologias. Conclusão O número de etiologias indeterminadas ainda é elevado e a infecção congênita por CMV pode ser uma possível causa de etiologia não diagnosticada para perda auditiva. A predominância das etiologias relacionadas às condições neonatais e às causas infecciosas são características de países em desenvolvimento. A mutação mais prevalente foi a 35delG e o principal gene foi o GJB2, provavelmente devido à influência europeia no genótipo de nossa população.

Assessment of Eustachian tube function in patients with tympanic membrane retraction and in normal subjects.

INTRODUCTION: The diagnosis of Eustachian tube dysfunctions is essential for better understanding of the pathogenesis of chronic otitis media. A series of tests to assess tube function are described in the literature; however, they are methodologically heterogeneous, with differences ranging from application protocols to standardization of tests and their results. OBJECTIVE: To evaluate the variation in middle ear pressure in patients with tympanic membrane retraction and in normal patients during tube function tests, as well as to evaluate intra-individual variation between these tests. METHODS: An observational, contemporary, cross-sectional study was conducted, in which the factor under study was the variation in middle ear pressure during tube function tests (Valsalva maneuver, sniff test, Toynbee maneuver) in healthy patients and in patients with mild and moderate/severe tympanic retraction. A total of 38 patients (76 ears) were included in the study. Patients underwent tube function tests at two different time points to determine pressure measurements after each maneuver. Statistical analysis was performed using SPSS software, version 18.0, considering p-values <0.05 as statistically significant. RESULTS: Mean (standard deviation) age was 11 (2.72) years; 55.3% of patients were male and 44.7% female. The prevalence of type A tympanogram was higher among participants with healthy ears and those with mild retraction, whereas type C tympanograms were more frequent in the moderate/severe retraction group. An increase in middle ear pressure was observed during the Valsalva maneuver at the first time point evaluated in all three groups of ears (p=0.012). The variation in pressure was not significant either for the sniff test or for the Toynbee maneuver at the two time points evaluated (p≥0.05). Agreement between measurements obtained at the two different time points was weak to moderate for all tests in all three groups of ears, and the variations in discrepancy between measurements were higher in ears with moderate/severe tympanic retraction. CONCLUSION: In this study population, the mean pressure in the middle ear showed significant variation only during the Valsalva maneuver at the first time point evaluated in the three groups of ears. Normal ears and those with mild retraction behaved similarly in all tests. The tested maneuvers exhibited weak to moderate intra-individual variation, with the greatest variation occurring in ears with moderate/severe retraction.

The contralateral ear in chronic otitis media: a series of 500 patients.

OBJECTIVE: To study the contralateral ear of patients with chronic otitis media (COM). DESIGN: Transversal. SETTING: Tertiary referral center. PATIENTS: A total of 500 consecutive patients who had been diagnosed as having COM with or without cholesteatoma. INTERVENTIONS: Digital otoendoscopy was performed on both ears. MAIN OUTCOME MEASURE: Pathologic alterations in the contralateral ear. RESULTS: In 75.2% of the patients, the contralateral ear was found to have some structural abnormalities; 60.4% of the patients presented with COM without cholesteatoma, and in this group, 69.9% had an abnormal contralateral ear. In those with cholesteatoma, the contralateral ear was found to be abnormal in 83.3%. The most frequent finding in both groups was retraction of the tympanic membrane. CONCLUSIONS: Patients with COM in 1 ear have a high chance of presenting with some degree of disease in the contralateral side. We believe that our findings suggest that COM should be ideally approached not as a static pathological incident affecting 1 ear but rather as an on-going process that may affect both ears.

Hearing impairment and socioeconomic factors: a population-based survey of an urban locality in southern Brazil.

OBJECTIVE: To provide the first population-based data on deafness and hearing impairment in Brazil. METHODS: In 2003, a cross-sectional household survey was conducted of 2,427 persons 4 years old and over. The study population was composed of 1,040 systematically chosen households in 40 randomly selected census tracts (dwelling clusters) in the city of Canoas, which is in the state of Rio Grande do Sul, in southern Brazil. Hearing function was evaluated in all subjects by both pure-tone audiometry and physical examination, using the World Health Organization Ear and Hearing Disorders Survey Protocol and definitions of hearing levels. The socioeconomic data that were gathered included the amount of schooling of all individuals tested and the income of the head of the household. RESULTS: It was found that 26.1% of the population studied showed some level of hearing impairment, and 6.8% (95% confidence interval (CI) = 5.5%-8.1%) were classified in the disabling hearing impairment group. The prevalence of moderate hearing loss was 5.4% (95% CI = 4.4%-6.4%); for severe hearing loss, 1.2% (95% CI = 0.7%-1.7%); and for profound hearing loss, 0.2% (95% CI = 0.03%-0.33%). The groups at higher risk for hearing loss were men (odds ratio (OR) = 1.54; 95% CI = 1.06-2.23); participants 60 years of age and over (OR = 12.55; 95% CI = 8.38-18.79); those with fewer years of formal schooling (OR = 3.92; 95% CI = 2.14-7.16); and those with lower income (OR = 1.56; 95% CI = 1.06-2.27). CONCLUSIONS: These results support advocacy by health policy planners and care providers for the prevention of deafness and hearing impairment. The findings could help build awareness in the community, in universities, and in government agencies of the health care needs that hearing problems create.

Histologic description of acquired cholesteatomas: comparison between children and adults.

UNLABELLED: Cholesteatoma is constituted of matrix, perimatrix and cystic content. Some authors affirm that, in children, its clinical behavior is more aggressive of the than in adults. AIMS: Histologic compared cholesteatomas of children and adults. METHODOLOGY: 74 cholesteatomas been analyzed, being 35 of pediatrics patients (<18 years). The average number of cellular layers and hyperplasia in the matrix had been evaluated; thickness, delimitante epithelium, fibrosis, inflammation and granuloma in the perimatrix. The analysis statistics was carried through with program SPSS 10.0, using the coefficients of Pearson and Spearman, test of chi-square and t test. The number of cellular layers in the matrix was of 8.2+/-4.2. The hyperplasia appears in 17%, fibrosis in 65%, granuloma in 12% and the delimitante epithelium in 21%. The perimatrix presented a medium one of 80 micrometers (37 the 232), minimum value zero and maximum value 1.926. The histological degree of inflammation was considered of moderate the accented one in 60%. When applying the coefficient of Spearman enters the inflammation degree and average of cellular layers of the matrix with the variables of the measure of thickness of the perimatrix we find correlations, significant, with moderate magnitudes of the great ones (rs=0.5 and P<0.0001). CONCLUSION: Adults colesteatomas of and child had not been identified to morphologic differences between. We find correlation enters the intensity of the inflammation and of the average of cellular layers of the matrix with the thickness of the perimatrix, what it can predict its aggressiveness, more studies are necessary to define the paper of this finding in pathogenesis of cholesteatoma.