Hereditary otovestibular dysfunction and Ménière's disease in a large Belgian family is caused by a missense mutation in the COCH gene.
OBJECTIVE
To report the clinical, auditory, and vestibular characteristics of a nonsyndromic otovestibular dysfunction in a large Belgian family caused by a missense mutation of the DFNA9 gene: COCH.


METHODS
Retrospective study of the clinical, audiologic, and vestibular data of 60 genetically affected cases.


METHODS
Tertiary referral center.


METHODS
All members of a Belgian kindred who carry the genetic (P51S) defect linked to the inherited hearing and vestibular impairment.


METHODS
Diagnostic otologic, audiometric, and vestibular analysis and imaging.


METHODS
Pure tone audiometry, supraliminary audiometry. and vestibular investigation.


RESULTS
The autosomal dominant inherited impairment was characterized by peripheral degeneration of the inner ear, leading to total deafness and bilateral vestibular areflexia.


CONCLUSIONS
The genetically affected persons of a Belgian family shared a progressive sensorineural hearing loss starting between the third and sixth decade. Vestibular symptoms started at about the same age as the hearing loss. The vestibular symptoms consisted of instability in darkness, a tendency to fall sideways, light-headiness, a drunken feeling, and attacks of vertigo. Most of the patients reported tinnitus, and half of them reported pressure in the ears. Clinically, 9 of the 60 patients met the criteria for definite Ménière's disease, and another 13 and 17 patients met the criteria for probable or possible Ménière's disease, respectively. All 9 were older than the age of 35, but only 1 was older than 55 years, so more than 30% of the patients were between 35 and 55 years old. A specific pattern could be recognized in the evolution of the otovestibular impairment. Under the age of 35 years, almost all the affected family members had normal hearing, whereas above the age of 55 years, the hearing loss was at least moderate, and vestibular hypofunction occurred. In between, there was a transition period of two to three decades, when deterioration of the cochleovestibular function occurred, with a temporary audiometric and vestibular asymmetry.
Verstreken
M
M
University Department of Otorhinolaryngology, University of Antwerp, Wilrijkstraat 10, B-2650 Antwerp, Belgium.
Declau
F
F
Wuyts
F L
FL
D'Haese
P
P
Van Camp
G
G
Fransen
E
E
Van den Hauwe
L
L
Buyle
S
S
Smets
R E
RE
Feenstra
L
L
Van der Stappen
A
A
Van de Heyning
P H
PH
D000328:Adult; D001301:Audiometry, Pure-Tone; D001302:Audiometry, Speech; D001530:Belgium; D002150:Caloric Tests; D004584:Electronystagmography; D005260:Female; D015870:Gene Expression; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics; D006801:Humans; D008297:Male; D008575:Meniere Disease / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology; D008875:Middle Aged; D020125:Mutation, Missense / Q000235:genetics*; D010375:Pedigree; D010579:Petrous Bone / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D012438:Saccades / Q000502:physiology; D014057:Tomography, X-Ray Computed; D015837:Vestibular Diseases / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology*; D014724:Vestibular Function Tests