Brainstem auditory evoked potentials in children with lead exposure

AbstractIntroductionEarlier studies have demonstrated an auditory effect of lead exposure in children, but information on the effects of low chronic exposures needs to be further elucidated.ObjectiveTo investigate the effect of low chronic exposures of the auditory system in children with a history of low blood lead levels, using an auditory electrophysiological test.MethodsContemporary cross-sectional cohort. Study participants underwent tympanometry, pure tone and speech audiometry, transient evoked otoacoustic emissions, and brainstem auditory evoked potentials, with blood lead monitoring over a period of 35.5 months. The study included 130 children, with ages ranging from 18 months to 14 years, 5 months (mean age 6 years, 8 months±3 years, 2 months).ResultsThe mean time-integrated cumulative blood lead index was 12μg/dL (SD±5.7, range: 2.433). All participants had hearing thresholds equal to or below 20dBHL and normal amplitudes of transient evoked otoacoustic emissions. No association was found between the absolute latencies of waves I, III, and V, the interpeak latencies I–III, III–V, and I–V, and the cumulative lead values.ConclusionNo evidence of toxic effects from chronic low lead exposures was observed on the auditory function of children living in a lead contaminated area

Case report: Guillain-Barre syndrome - language development delay

The aim of the study was to describe the Guillain-Barré syndrome development and speech and language pathology manifestations. It describes the clinical picture of a speech and language pathology, and the revaluation 7 months after the symptoms beginning, through formal and informal tests application and auditory evaluation. In the revaluation, the results showed intentional communication, primary functions, restricted participation in dialogic activity, isolated words productions, orders understanding linked to the context, alimentary abilities return. Peripheral audition normality. Hospitalization, family conducts front to the disease and absence of school activities influenced in the communicative acting. The Guillain-Barré syndrome emergence, as well as the family answer to the child’s condition, influenced in a negative way the language development.O objetivo deste estudo foi descrever o desenvolvimento da síndrome de Guillain-Barré e manifestações fonoaudiológicas. É relatado breve histórico do quadro clínico e reavaliação fonoaudiológica 7 meses após o início dos sintomas, por meio de aplicação de testes formais, informais e avaliação audiológica. Na reavaliação, os resultados indicaram comunicação intencional, funções primárias, restrita participação em atividade dialógica, produções de palavras isoladas, compreensão de ordens ligadas ao contexto, retorno das habilidades alimentares. Foi constatada normalidade da audição periférica. Hospitalização, condutas familiares frente à doença e ausência de atividades escolares influenciaram no desempenho comunicativo. O aparecimento da Síndrome de Guillain-Barré influenciou de forma negativa no desenvolvimento da linguagem, assim como a resposta familiar à condição da criança

Audiological evaluation in children with low level of cumulative lead exposure

OBJETIVO: verificar a ocorrência de perda auditiva sensorioneural em crianças com baixo nível de exposição cumulativa ao chumbo. MÉTODO: 156 crianças intoxicadas por chumbo, 94 do sexo masculino e 62 do sexo feminino, na faixa etária entre 18 meses a 14 anos e 5 meses, foram submetidas a análise longitudinal do nível de Plumbemia em sangue, bem como audiometria tonal liminar e emissões otoacústicas evocadas por estímulo transiente. RESULTADOS: a população pesquisada apresentou um valor médio de Plumbemia estimada de 12,2±5,7mg/dL (faixa entre 2,4-33mg/dL); todas as crianças apresentaram resposta normal na audiometria tonal liminar em 20 dBNA nas frequências testadas, 0,5; 1; 2 e 4 kHz, para ambas as orelhas; as emissões otoacústicas evocadas por estímulo transiente estiveram presentes para todas as frequências bilateralmente, nas 79 crianças pesquisadas. CONCLUSÃO: não foi constatada perda auditiva sensorioneural em crianças com histórico de baixo nível de exposição cumulativa por chumbo, assim como não foi encontrada lesão de células ciliadas externas na cóclea, mesmo que subclínicas

Perda auditiva e síndrome da imunodeficiência adquirida: revisão sistemática

PURPOSE: To investigate the occurrence of hearing loss in individuals with HIV/AIDS and their characterization regarding type and degree. RESEARCH STRATEGY: It was conducted a systematic review of the literature found on the electronic databases PubMed, EMBASE, ADOLEC, IBECS, Web of Science, Scopus, Lilacs and SciELO. SELECTION CRITERIA: The search strategy was directed by a specific question: "Is hearing loss part of the framework of HIV/AIDS manifestations?", and the selection criteria of the studies involved coherence with the proposed theme, evidence levels 1, 2 or 3, and language (Portuguese, English and Spanish). DATA ANALYSIS: We found 698 studies. After an analysis of the title and abstract, 91 were selected for full reading. Out of these, 38 met the proposed criteria and were included on the review. RESULTS: The studies reported presence of conductive, sensorineural, and mixed hearing loss, of variable degrees and audiometric configurations, in addition to tinnitus and vestibular disorders. The etiology can be attributed to opportunistic infections, ototoxic drugs or to the action of virus itself. The auditory evoked potentials have been used as markers of neurological alterations, even in patients with normal hearing. CONCLUSION: HIV/AIDS patients may present hearing loss. Thus, programs for prevention and treatment of AIDS must involve actions aimed at auditory health

Consistent patterns of common species across tropical tree communities

Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.Publisher PDFPeer reviewe

Relato de caso: síndrome de Guillain-Barré - atraso do desenvolvimento da linguagem

O objetivo deste estudo foi descrever o desenvolvimento da síndrome de Guillain-Barré e manifestações fonoaudiológicas. É relatado breve histórico do quadro clínico e reavaliação fonoaudiológica 7 meses após o início dos sintomas, por meio de aplicação de testes formais, informais e avaliação audiológica. Na reavaliação, os resultados indicaram comunicação intencional, funções primárias, restrita participação em atividade dialógica, produções de palavras isoladas, compreensão de ordens ligadas ao contexto, retorno das habilidades alimentares. Foi constatada normalidade da audição periférica. Hospitalização, condutas familiares frente à doença e ausência de atividades escolares influenciaram no desempenho comunicativo. O aparecimento da Síndrome de Guillain-Barré influenciou de forma negativa no desenvolvimento da linguagem, assim como a resposta familiar à condição da criança.The aim of the study was to describe the Guillain-Barré syndrome development and speech and language pathology manifestations. It describes the clinical picture of a speech and language pathology, and the revaluation 7 months after the symptoms beginning, through formal and informal tests application and auditory evaluation. In the revaluation, the results showed intentional communication, primary functions, restricted participation in dialogic activity, isolated words productions, orders understanding linked to the context, alimentary abilities return. Peripheral audition normality. Hospitalization, family conducts front to the disease and absence of school activities influenced in the communicative acting. The Guillain-Barré syndrome emergence, as well as the family answer to the child’s condition, influenced in a negative way the language development

Correlation analysis of the long latency auditory evoked potential N2 and cognitive P3 with the level of lead poisoning in children

Introduction: The effects of lead on children's health have been widely studied. Aim: To analyze the correlation between the long latency auditory evoked potential N2 and cognitive P3 with the level of lead poisoning in Brazilian children. Methods: This retrospective study evaluated 20 children ranging in age from 7 to 14 years at the time of audiological and electrophysiological evaluations. We performed periodic surveys of the lead concentration in the blood and basic audiological evaluations. Furthermore, we studied the auditory evoked potential long latency N2 and cognitive P3 by analyzing the absolute latency of the N2 and P3 potentials and the P3 amplitude recorded at Cz. At the time of audiological and electrophysiological evaluations, the average concentration of lead in the blood was less than 10 ug/dL. Results: In conventional audiologic evaluations, all children had hearing thresholds below 20 dBHL for the frequencies tested and normal tympanometry findings; the auditory evoked potential long latency N2 and cognitive P3 were present in 95% of children. No significant correlations were found between the blood lead concentration and latency (p = 0.821) or amplitude (p = 0.411) of the P3 potential. However, the latency of the N2 potential increased with the concentration of lead in the blood, with a significant correlation (p = 0.030). Conclusion: Among Brazilian children with low lead exposure, a significant correlation was found between blood lead levels and the average latency of the auditory evoked potential long latency N2; however, a significant correlation was not observed for the amplitude and latency of the cognitive potential P3

Characterization of patients with tinnitus seen by the Hearing Health service

ABSTRACT Purpose: to establish the profile of individuals with tinnitus treated at a Hearing Health service and to associate the symptom with gender, audiological profile, and presence of vertigo. Methods: a descriptive, retrospective study with an analysis of 6,000 medical records of individuals treated at a hearing health service was carried out. The data collected from the medical records were: sociodemographic data, characteristics of hearing impairment, characteristics of tinnitus and vertigo, speech therapy interview, and otorhinolaryngological, audiological, otoneurological assessments, characteristics of life style and risk factors. An descriptive analysis was performed using the Chi-square test of association, adopting a statistical significance level of 5% (p<0.05) for the inferential analysis. Results: there was a statistically significant association between the presence of tinnitus and gender, normal hearing, and vertigo, and a significant association was also found between tinnitus and unilateral and bilateral conductive hearing loss, and unilateral and bilateral sensorineural hearing loss. Conclusion: there was a significant association, in the population evaluated, for the presence of tinnitus and female gender, normal hearing, unilateral and bilateral conductive hearing loss, unilateral and bilateral sensorineural hearing loss, and the presence of vertigo