Study of a Brazilian family presenting non-syndromic hearing loss with mitochondrial inheritance

O presente estudo teve como objetivo descrever os achados audiológicos e genéticos de nove membros de uma família brasileira que apresenta a mutação no DNA mitocondrial. Todos os nove membros realizaram estudo genético, avaliação foniátrica e audiológica (audiometria tonal e logoaudiometria). O estudo genético revelou a presença de mutação mitocondrial A1555G no gene 12S rRNA (MT-RNR-1) do DNA mitocondrial em todos os sujeitos. Oito sujeitos apresentaram deficiência auditiva e somente um apresentou limiares auditivos normais até o término da realização do estudo. Os resultados audiológicos apontaram para perdas auditivas bilaterais, com prevalência das simétricas, de configurações e graus variados (de moderado a profundo) e pós-linguais. Progressão da perda auditiva foi observada em dois irmãos afetados. Não foi possível afirmar a época do início da perda auditiva por falta de informação dos sujeitos, no entanto, observou-se manifestação da perda em crianças e adultos. As mutações no DNA mitocondrial representam uma causa importante de perda auditiva, sendo imprescindível a realização do diagnóstico etiopatológico, a fim de retardar o início ou evitar a progressão da surdez.We hereby report on the audiological and genetic findings in individuals from a Brazilian family, with the following mitochondrial mutation A1555G in the 12SrRNA gene (MT-RNR-1). Nine individuals underwent speech, audiologic (tonal audiometry and logoaudiometry) and genetic evaluations. Eight individuals among the A1555G carriers were affected by hearing impairment and one person had normal hearing thresholds till the end of the present study. The audiologic evaluation results indicated normal hearing thresholds all the way to bilateral profound hearing loss with post-lingual onset and variable configuration. Two affected siblings presented progressive hearing loss. It was impossible to precise the time of hearing loss onset; however, the impairment was present in both children and adults. The genetic study revealed the A1555G mitochondrial mutation in the 12SrRNA gene. Given the prevalence of mitochondrial mutations as a cause of hearing loss, it is fundamental to perform the etiopathologic diagnosis in order to postpone the onset or avoid hearing impairment progression. This kind of hearing impairment represents a challenge to the professionals since there are no physical traits that indicate genetic transmission

Reading and comprehension: phoniatric assessment in students with reading difficulties

Introduction: Reading is a highly refined skill that encompasses two main components: decoding graphic symbols and understanding the written message. These aspects generally develop together, but reading comprehension is a much more complex process, sustained not only by the identification of written words and vocabulary but also by language systems, such as syntax and general knowledge. Although there is a well-established technique for performing the phoniatric assessment, there is no common use of tests that assess reading comprehension or the association of this information with other assessment data. Objective: The objective of this study is, in the context of the phoniatric consultation, to evaluate the reading and retelling in children with relevant reading difficulties and to correlate the decoding and comprehension problems with the alterations observed in auditory and visual perceptual tests, pointing out the evidence that best contributed to the differential diagnosis of these subjects. Methods: Starting from a population of 301 children enrolled in the 4th and 5th grades of elementary school, 13 children with evident reading and writing difficulties were evaluated regarding the reading and retelling tasks and separated into groups according to the problem of decoding, fluency, and comprehension. Reading performance was correlated with the performance in visual and auditory perceptual tests and based on the similarity analysis, the tests considered to be the most relevant in the diagnosis process of these children were identified. Result: The results suggest that the tasks: naming of figures, repetition of numbers in reverse order, figure copying, syllabic synthesis, phonemic synthesis, rhyme, and phonemic manipulation altogether contribute to diagnosis and multidisciplinary intervention aspects. Conclusion: Some tasks are more relevant to the diagnostic process of children with complaints of learning difficulties in reading