RESUMO
OBJECTIVE: The aim of this study was to describe audiological and radiological characteristics, and other secondary aspects, in a family carrying a T961G mutation in the 12S rRNA mitochondrial gene. DESIGN: Case report. STUDY SAMPLE: Six members of a family participated in an audiological evaluation that included pure-tone audiometry, immittance tests, auditory brainstem responses (ABR), and otoacoustic emissions (OAE). The radiological evaluation was conducted through temporal bone CT scans using a Toshiba 16 channels Aquilon Spirale. Neuropsychiatric evaluation was also administered. RESULTS: Three participants were diagnosed with severe sensorineural hearing loss of cochlear origin and cochlear malformations visible in CT scans. One participant had a mild mixed-hearing loss and no cochlear malformations. Two participants had normal audiological and radiological findings. CONCLUSIONS: We believe our study can provide helpful insight on the clinical findings of a rare mutation, of which few data have been presented in literature.
Assuntos
Anormalidades Múltiplas , Cóclea/anormalidades , Perda Auditiva Condutiva-Neurossensorial Mista/genética , Perda Auditiva Neurossensorial/genética , Audição/genética , Mutação , RNA Ribossômico/genética , RNA/genética , Aqueduto Vestibular/anormalidades , Adulto , Audiometria de Tons Puros , Percepção Auditiva/genética , Limiar Auditivo , Criança , Pré-Escolar , Cóclea/diagnóstico por imagem , Cóclea/fisiopatologia , Potenciais Evocados Auditivos do Tronco Encefálico/genética , Feminino , Predisposição Genética para Doença , Testes Genéticos/métodos , Perda Auditiva Condutiva-Neurossensorial Mista/diagnóstico , Perda Auditiva Condutiva-Neurossensorial Mista/fisiopatologia , Perda Auditiva Condutiva-Neurossensorial Mista/psicologia , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Neurossensorial/psicologia , Hereditariedade , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Emissões Otoacústicas Espontâneas/genética , Linhagem , Fenótipo , Valor Preditivo dos Testes , RNA Mitocondrial , Tomografia Computadorizada Espiral , Aqueduto Vestibular/diagnóstico por imagem , Aqueduto Vestibular/fisiopatologiaRESUMO
OBJECTIVE: In this study, we have evaluated by means of auditory brainstem responses (ABR), in a population derived from a newborn hearing screening protocol, some aspects of maturation of the auditory pathways in the first months after birth, and the possible repercussions on early treatment. MATERIALS AND METHODS: In this retrospective study newborns were recruited through our hearing screening program, and an ABR evaluation was performed on 339 newborns, that had risk factors or had failed the screening, or both. Such population was divided in two groups for statistical analysis purposes: full-term and pre-term. The initial ABR was pathological in 70 infants. RESULTS: We observed an improvement over time of the estimated hearing threshold in follow-up ABRs in 43 newborns (26 in the full-term group, mean improvement 27.9 dB SPL, and 17 in the pre-term group, mean improvement 34.6 dB SPL); such an improvement might be related to a maturation of the auditory pathways that was not complete at birth. CONCLUSIONS: The auditory system might not be completely developed at birth, and might require some months to complete; hence any early clinical approach should consider the possibility of an overtreatment, and any therapeutic strategy should only be considered once the diagnosis is certain and definitive.