title: Electrophysiological analysis shows dizziness as the first symptom in human T cell lymphotropic virus type-associated myelopathy/tropical spastic paraparesis.
abstract: Dizziness is a symptom in human T cell lymphotropic virus type-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and may occur due to vestibulospinal tract dysfunction. This tract can be assessed by an electrophysiological test called vestibular-evoked myogenic potential (VEMP). The aim was to correlate the result of VEMP generated by acoustic stimuli and dizziness in individuals with human T cell lymphotropic virus type 1 (HTLV-1)-asymptomatic infection and HAM/TSP. VEMP was recorded from the sternocleidomastoid muscle of 60 HTLV-1-negative adults (60±8 years) and 60 individuals infected with HTLV-1, 30 being asymptomatic (59±8 years) and 30 with HAM/TSP (59±8 years). In all groups, 90% of the participants were women. VEMP was generated by acoustic stimuli (short tone bursts), with an intensity of 118 dBHL and band-pass filter from 10 Hz to 1,500 Hz, and presented 200 stimuli at a frequency of 1,000 Hz with a record time of 60 ms. Of 60 HTLV-1-negative individuals, 14 (23%) reported dizziness; VEMP was normal in all. In the HTLV-1-asymptomatic group, 11(37%) complained of dizziness (p=0.31); VEMP was altered in four (40%) subjects with dizziness and in one (5%) without dizziness (p=0.00). In the group with HAM/TSP, dizziness was reported by 17 (57%) subjects (p=0.002); VEMP was altered in 11 (64%) with dizziness and in 5 (38%) without dizziness (p=0.15). Dizziness without an apparent etiology in HTLV-1-asymptomatic carriers deserves attention in terms of a possible subclinical spinal cord involvement that can be clarified through spinal electrophysiological tests. Damage of the vestibulospinal tract seems to occur in the early stages of HAM/TSP.
authors.affiliation: 1Tropical Medicine Post Graduate Program, Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.|2Interdisciplinary HTLV Research Group (GIPH), Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Ludimila
authors.initials: L
authors.lastname: Labanca
authors.affiliation: 1Tropical Medicine Post Graduate Program, Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.|2Interdisciplinary HTLV Research Group (GIPH), Belo Horizonte, Minas Gerais, Brazil.|3Minas Gerais State Center of Hematology and Blood Transfusion (Fundação Hemominas), Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Ana Lúcia Borges
authors.initials: AL
authors.lastname: Starling
authors.affiliation: 1Tropical Medicine Post Graduate Program, Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Silvio Roberto
authors.initials: SR
authors.lastname: de Sousa-Pereira
authors.affiliation: 2Interdisciplinary HTLV Research Group (GIPH), Belo Horizonte, Minas Gerais, Brazil.|3Minas Gerais State Center of Hematology and Blood Transfusion (Fundação Hemominas), Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Luiz Cláudio Ferreira
authors.initials: LC
authors.lastname: Romanelli
authors.affiliation: 2Interdisciplinary HTLV Research Group (GIPH), Belo Horizonte, Minas Gerais, Brazil.|3Minas Gerais State Center of Hematology and Blood Transfusion (Fundação Hemominas), Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Anna Bárbara
authors.initials: AB
authors.lastname: de Freitas Carneiro-Proietti
authors.affiliation: 1Tropical Medicine Post Graduate Program, Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Lucas Novaes
authors.initials: LN
authors.lastname: Carvalho
authors.affiliation: 1Tropical Medicine Post Graduate Program, Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Daniele Rosa
authors.initials: DR
authors.lastname: Fernandes
authors.affiliation: 1Tropical Medicine Post Graduate Program, Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.|2Interdisciplinary HTLV Research Group (GIPH), Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Denise
authors.initials: D
authors.lastname: Utsch Gonçalves
mesh_terms: D000328:Adult; D000368:Aged; D004244:Dizziness / Q000503:physiopathology* / Q000821:virology*; D055724:Electrophysiological Phenomena; D005260:Female; D015490:HTLV-I Infections / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009132:Muscles / Q000502:physiology