Case Report: Cognitive Impairment without Clinical Spinal Disease May Be the First Sign of HTLV-1 Neurological Alteration.

Human t-cell lymphotropic virus type 1 (HTLV-1)-associated myelopathy (HAM) is a progressive neurological disease whose diagnosis is defined by clinical manifestations and seropositivity for HTLV-1 infection. Cognitive impairment (CI) is considered to occur after spinal impairment. A 51-year-old HTLV-1-infected man classified as an asymptomatic carrier presented difficulties in listening comprehension and executive memory. He was assessed for central auditory processing (CAP), cognition (event-related auditory evoked potential [P300]), and otoneurological functions (galvanic vestibular-evoked myogenic potential [gVEMP]). Altered responses were found in CAP, P300, and gVEMP, but the neurological examination and cognitive screening were normal. After a 2-year follow-up, we disclosed a positive Babinski sign, a mild CI, worsened P300, and gVEMP latencies, and the patient reported progressive lumbar pain and difficulty running. He was, then, reclassified as HAM. The first examination, in 2016, had already shown abnormal results in P300 and gVEMP despite the HTLV-1-asymptomatic carrier status. Therefore, tests that provide subclinical measures of neurological disease progression can be useful tools for an early diagnosis and intervention in HTLV-1 patients. Electrophysiological results had worsened as well as the clinical status and the cognitive function and the progression from asymptomatic status to an HTLV-1-associated neurological disease occurred within 2 years. Thus, HTLV-1-infected individuals with complaints of CI, hearing, or otoneurological manifestations should be submitted to neuropsychological and electrophysiological tests, allowing them to be properly cared in case of HAM progression.

Potencial Evocado Auditivo de Média Latência (PEAML) em crianças e adolescentes brasileiros: revisão sistemática / Middle Latency Responses (MLR) in Brazilian children and adolescents: systematic review

RESUMO Objetivo: Revisar sistematicamente a literatura científica sobre a realização do Potencial Evocado Auditivo de Média Latência (PEAML) em crianças e adolescentes brasileiros. Estratégia de pesquisa: Foram pesquisados artigos publicados a partir de 2009, em português, inglês ou espanhol, nas bases de dados eletrônicas MEDLINE, SciELO, BIREME e LILACS. Os artigos selecionados envolveram a realização do PEAML em crianças e/ou adolescentes brasileiros. Após triagem, os artigos foram analisados segundo a iniciativa “Strengthening the Reporting of Observational Studies in Epidemiology” (STROBE). Critérios de seleção: Foram excluídos artigos repetidos nas bases de busca e também os relatos de caso. Resultados: A busca inicial identificou 1315 artigos, dos quais oito foram selecionados para compor a revisão. Verificou-se predomínio de estudos observacionais transversais (75%); estimulação tipo click (100%), com velocidade até 11/s (100%) e intensidade de 70 dBNA (88%); uso de filtro passa-alta de 10 Hz (50%) e passa-baixa de 200 Hz (75%); montagem dos eletrodos em C3/C4 (ativos) A1/A2 (referências), e Fpz (neutro) (88%); amplitude Na-Pa, como principal parâmetro de comparação e normalidade; e uso do teste ANOVA (63%) para análise estatística. Nos estudos revisados, a média da latência da onda Pa e da amplitude Na-Pa em crianças e adolescentes normo-ouvintes foi de 32 milissegundos e 1,57 microvolts, respectivamente. Conclusão: Não há consenso quanto aos parâmetros de registro do PEAML em crianças e adolescentes brasileiros. Ainda assim, a média de latência de Pa e amplitude Na-Pa encontrada em crianças e adolescentes brasileiros normo-ouvintes, avaliados nos oito artigos desta revisão, concorda com os parâmetros de normalidade já estabelecidos internacionalmente.

ABSTRACT Purpose: Systematically review the scientific literature on Middle Latency Response (MLR) in Brazilian children and adolescents. Research strategy: We searched articles published since 2009 in Portuguese, English or Spanish at MEDLINE, SciELO, BIREME and LILACS electronic basis. Selected articles involved the use of MLR in children and / or Brazilian adolescents. After screening process, articles were analyzed according to “Strengthening the Reporting of Observational Studies in Epidemiology” (STROBE) initiative. Selection criteria: Repeated articles (due to database repetition) and case reports were excluded. Results: From 1315 identified articles, eight were selected for the review. It was predominantly observed: cross-sectional studies (75%); click stimulation (100%), with rate up to 11/s (100%) and 70 dBHL intensity (88%); filtering high-pass 10 Hz (50%) and low-pass 200 Hz (75%); electrode array with actives placed at C3/C4, references at A1/A2 and neutral at Fpz (88%); Na-Pa amplitude as main measure of comparison and normality; and the use of ANOVA test (63%) for statistical analyses. The average latency of Pa wave and Na-Pa amplitude in normal-hearing children and adolescents of the studies was 32 milliseconds and 1.57 microvolts respectively. Conclusion: There is no consensus on MLR collection parameters in Brazilian children and adolescents. Still, the Pa latency average and Na-Pa amplitude found in Brazilian normal-hearing children and adolescents evaluated on the eight articles of this review agreed with normative parameters established internationally.