Immunological responses in acute low-tone sensorineural hearing loss and Ménière's disease.
OBJECTIVE
The autoimmune response appears to play an important role in some types of acute sensorineural hearing loss. Endolymphatic hydrops associated with fluctuating hearing loss has also been suggested to be caused by an immunological mechanism. Acute low-tone hearing loss (ALHL) associated with Ménière's disease (MD) is characterized by fluctuating hearing loss, and its etiology is thought to involve endolymphatic hydrops. The aim of this study was to attempt to determine the etiology of ALHL in MD.


METHODS
A flow cytometer was used to analyze intracellular cytokine levels in peripheral blood from 19 patients with ALHL and 26 patients with MD and the data compared to those obtained from age- and gender-matched healthy volunteers.


RESULTS
The patients with ALHL showed significantly increased levels of Th1 subsets (interferon-gamma-producing helper T cells) as compared to those in normal controls. The levels of Th2 (IL-4-producing helper T cells) subsets did not differ from those in the control group and thus Th1 predominated in ALHL patients. The patients with MD showed significantly increased natural killer cell activity but no Th1 dominance. These patients had no obvious systemic or local disease except in the inner ear.


CONCLUSIONS
An abnormality of the Th1/Th2 balance in ALHL and increased natural killer cell activity in MD are thought to relate to inner ear disorder. These results are consistent with the possibility that the etiology of ALHL and MD involves an immune response.
Fuse
Takeo
T
Department of Otolaryngology, Yamagata University School of Medicine, Yamagata, Japan. tafuse@med.id.yamagata-u.ac.jp
Hayashi
Tomohiro
T
Oota
Nobuo
N
Fukase
Shigeru
S
Asano
Shinichirou
S
Kato
Takeo
T
Aoyagi
Masaru
M
D000208:Acute Disease; D000328:Adult; D001301:Audiometry, Pure-Tone; D001327:Autoimmune Diseases / Q000175:diagnosis / Q000276:immunology*; D018791:CD4 Lymphocyte Count; D016207:Cytokines / Q000097:blood*; D018159:Endolymphatic Hydrops / Q000175:diagnosis / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis / Q000276:immunology*; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology; D007958:Leukocyte Count; D008297:Male; D008575:Meniere Disease / Q000175:diagnosis / Q000276:immunology*; D008875:Middle Aged; D010897:Pitch Discrimination / Q000502:physiology; D012016:Reference Values; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology
D016207:Cytokines