Stable and progressive hearing loss in type 2A Usher's syndrome.
Audiograms were traced or additionally performed on 23 Usher's syndrome patients in 10 Dutch multi-affected families, all linked to chromosome 1q (USH2A locus). Serial audiograms, available in 13 patients, were used for a regression analysis of binaural pure tone average on age (follow-up, 9 to 32 years) to test for "significant progression," ie, a significant regression coefficient, here called the "annual threshold increase" (ATI, expressed in decibels per year). A significant ATI (> 1 dB/y) was observed in 3 patients. Analysis of variance of ATI demonstrated significant heterogeneity; hearing loss was either stable or progressive. This implies a significant clinical heterogeneity. A similar analysis performed on our progressive USH2A cases and "type III" cases previously reported by others (ATI of 1 to 5 dB/y), some of which were recently linked to chromosome 3q (USH3 locus), failed to show any significant heterogeneity in the progression of hearing loss.
van Aarem
A
A
Department of Otorhinolaryngology, University Hospital Nijmegen, The Netherlands.
Pinckers
A J
AJ
Kimberling
W J
WJ
Huygen
P L
PL
Bleeker-Wagemakers
E M
EM
Cremers
C W
CW
D000293:Adolescent; D000328:Adult; D001299:Audiometry; D002648:Child; D002675:Child, Preschool; D002878:Chromosomes, Human, Pair 1; D005260:Female; D005808:Genes, Recessive; D008040:Genetic Linkage; D006319:Hearing Loss, Sensorineural / Q000151:congenital* / Q000175:diagnosis / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D012174:Retinitis Pigmentosa / Q000235:genetics / Q000503:physiopathology*; D013577:Syndrome