title: Is human T-lymphotropic virus type 1 infection associated with hearing loss?
abstract: OBJECTIVE
  Human T-lymphotropic virus type 1 (HTLV-1) infection is endemic in the northeast area of Iran. Although various neurological disturbances have been reported in HTLV-1 infection, possible audiovestibular involvement during this infection has not yet been studied.
  
  
  METHODS
  Case control study.
  
  
  METHODS
  Sixty-eight cases in three groups including 24 HTLV-1-infected patients with HTLV-1- associated myelopathy/tropical spastic paraparesis (HAM/TSP) (group 1), 23 HTLV-1-infected cases without clinical presentation (group 2), and 21 normal individuals (group 3) entered our study. A complete history of hearing-related disorders and a profile of audiologic tests, including pure-tone audiometry (PTA) with high frequencies, speech reception threshold (SRT), and auditory brainstem response (ABR) were taken.
  
  
  RESULTS
  Subjective audiovestibular complaints of participants showed a significant difference among HAM/TSP patients and the two other groups regarding hearing loss and tinnitus, but not vertigo or aural fullness. Hearing evaluation by SRT and PTA in all frequencies showed a significant difference between HAM/TSP patients (group 1) and the controls (group 3). The difference was also significant between asymptomatic cases (group 2) and the controls only in PTA frequencies above 4 kHz. Auditory brainstem-evoked potential did not show any significant differences among the groups regarding latency of I, III, and V waves and interwave differences.
  
  
  CONCLUSIONS
  HTLV-1 infection, particularly in those with a clinical presentation, appears to accompany hearing loss. Based on the results of PTA and ABR tests, this study may suggest a cochlear source of hearing impairment rather than neural problems.
authors.affiliation: Sinus and Surgical Endoscopic Research Center.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Bakhshaee
authors.forename: Amirhossein
authors.initials: A
authors.lastname: Sorouri
authors.forename: Ali
authors.initials: A
authors.lastname: Shoeibi
authors.forename: Reza
authors.initials: R
authors.lastname: Boustani
authors.forename: Farideh
authors.initials: F
authors.lastname: Golhasani-Keshtan
authors.forename: Amin
authors.initials: A
authors.lastname: Amali
authors.forename: Mohsen
authors.initials: M
authors.lastname: Rajati
mesh_terms: D000328:Adult; D001301:Audiometry, Pure-Tone / Q000379:methods; D016022:Case-Control Studies; D015897:Comorbidity; D019353:Endemic Diseases; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology; D005260:Female; D015490:HTLV-I Infections / Q000175:diagnosis* / Q000453:epidemiology*; D034381:Hearing Loss / Q000175:diagnosis* / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D007492:Iran / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D038781:Otoscopy / Q000379:methods; D015493:Paraparesis, Tropical Spastic / Q000175:diagnosis / Q000453:epidemiology*; D011379:Prognosis; D012016:Reference Values; D018570:Risk Assessment; D012720:Severity of Illness Index
keywords: HTLV-1-associated myelopathy and tropical spastic paraparesis; Human T-lymphotropic virus type 1; hearing; tinnitus; vertigo