Progress towards early detection services for infants with hearing loss in developing countries

BACKGROUND: Early detection of infants with permanent hearing loss through infant hearing screening is recognised and routinely offered as a vital component of early childhood care in developed countries. This article investigates the initiatives and progress towards early detection of infants with hearing loss in developing countries against the backdrop of the dearth of epidemiological data from this region. METHODS: A cross-sectional, descriptive study based on responses to a structured questionnaire eliciting information on the nature and scope of early hearing detection services; strategies for financing services; parental and professional attitudes towards screening; and the performance of screening programmes. Responses were complemented with relevant data from the internet and PubMed/Medline. RESULTS: Pilot projects using objective screening tests are on-going in a growing number of countries. Screening services are provided at public/private hospitals and/or community health centres and at no charge only in a few countries. Attitudes amongst parents and health care workers are typically positive towards such programmes. Screening efficiency, as measured by referral rate at discharge, was generally found to be lower than desired but several programmes achieved other international benchmarks. Coverage is generally above 90% but poor follow-up rates remain a challenge in some countries. The mean age of diagnosis is usually less than six months, even for community-based programmes. CONCLUSION: Lack of adequate resources by many governments may limit rapid nationwide introduction of services for early hearing detection and intervention, but may not deter such services altogether. Parents may be required to pay for services in some settings in line with the existing practice where healthcare services are predominantly financed by out-of-pocket spending rather than public funding. However, governments and their international development partners need to complement current voluntary initiatives through systematic scaling-up of public awareness and requisite manpower development towards sustainable service capacities at all levels of healthcare delivery

Effects of maturation on parameters used for pass/fail criteria in neonatal hearing screening programmes using evoked otoacoustic emissions

We aimed to investigate the incidence of false alarms that occurred with the pass/fail criteria used in a published series of neonatal hearing screening programmes, as a function of age. We analysed the database of 19137 normally hearing babies (38274 ears) tested in the Wessex Universal Neonatal Hearing Screening Project. Otoacoustic emissions were recorded prior to discharge from maternity units, using IL088 equipment. We assessed the pass/fail rate using the Wessex criteria and 10 other pass/fail criteria published in the literature. Using Pearson's correlation coefficient, a statistically significant correlation between signal-to-noise ratio at each of the frequency bands 1, 2, 3, 4 and 5 kHz and babies' age in hours at the 0.01 level was identified. The correlation was also significant (0.01 level) between age and frequency reproducibility in each of the bands at 1, 2, 3, 4 and 5 kHz as well as the whole reproducibility. The number of false alarms reduced significantly after the first 24 h of life with all the criteria examined. We conclude that in the first hours after birth due to insufficient maturation of the otoacoustic emission, there is a high rate of false alarms. This increase in the false alarm rate, whilst dependent on the criteria used, occurs with all criteria. This leads to the consideration of whether the establishment of age-dependent pass/fail criteria could reduce the false alarm rate and the subsequent strain on diagnostic centres. Copyright (c) 2007 S. Karger AG, Base

Acompanhamento do desenvolvimento da linguagem de lactentes de risco para surdez Follow-up of language development in infants with risk factors for hearing loss

OBJETIVO: Comparar o desenvolvimento da linguagem, de acordo com o gênero, idade gestacional e peso ao nascimento, aos quatro, oito e 12 meses, de lactentes que permaneceram em UTI Neonatal e que apresentaram um ou mais indicadores de risco para perda auditiva de aparecimento tardio. MÉTODOS: Estudo longitudinal de lactentes nascidos entre agosto de 2007 e julho de 2008 que, na UTI, apresentaram resultado normal no Potencial Evocado Auditivo de Tronco Encefálico, e que necessitaram de monitoramento audiológico e de linguagem, por apresentarem indicadores de risco para perda auditiva. Os lactentes foram avaliados no 4º, 8º e 12° meses de vida por meio da Escala de Aquisições Iniciais de Linguagem. RESULTADOS: Compareceram a todas as avaliações 87 lactentes e 60 (69%) apresentaram como indicador de risco a permanência na UTI associada à hipertensão pulmonar. Na Escala de Aquisições Iniciais de Linguagem, nove lactentes apresentaram alterações aos quatro meses e 11 lactentes aos oito meses de idade. Aos 12 meses, 18 (20,6%) lactentes apresentaram alteração e desses, cinco tiveram atraso nos meses anteriores. Os dados estatísticos demonstraram que resultados alterados aos quatro e oito meses podem predizer dificuldades nas respostas dos lactentes aos 12 meses. Houve o aparecimento de desvios transitórios no desenvolvimento da linguagem oral, normalizados na maioria dos casos. CONCLUSÃO: Deve-se realizar a avaliação de linguagem no primeiro ano de vida a fim de monitorar possíveis atrasos em lactentes com indicador de risco para surdez.<br>PURPOSE: To compare language development, according to gender, gestational age and birth weight, at four, eight and 12 months of life, of infants who remained in the Neonate Intensive Care Unit, who presented at least one risk factor for hearing loss with delayed onset. METHODS: Longitudinal study of infants born between August 2007 and July 2008, who, in the Intensive Care Unit (ICU), showed normal results in the Automated Auditory Brainstem Evoked Potential test, and required audiological and language monitoring for presenting risk factors for hearing loss. The infants were assessed at four, eight and 12 months, using the Early Language Milestone Scale. RESULTS: Eighty-seven infants were evaluated, and 60 (69%) of them presented, as a risk factor, the permanence at the ICU associated with pulmonary hypertension. In the Early Language Milestone Scale, nine infants showed alterations at four months, and 11 at eight months of age. At 12 months, 18 (20.6%) infants showed alterations, and five of these had showed delays in the previous evaluations. Statistical analyses demonstrated that altered results at four and eight months can predict difficulties in the infant's responses at 12 months. The infants showed transitory alterations in oral language development, which were overcome in most cases. CONCLUSION: The first language evaluation of children with risk factors for hearing loss should be carried during the first year of life, allowing early detection of language development issues