Hearing loss in Townes-Brocks syndrome.

Townes-Brocks syndrome is an autosomal dominant syndrome consisting of anomalies affecting the ear, hand, foot, anus, and kidney. Anomalies affecting the ear include lop ear, preauricular skin tags, ossicular abnormalities, and a mixed hearing loss. The hearing loss in Townes-Brocks syndrome is predominantly sensorineural, affects high-frequency thresholds more than low-frequency thresholds, and has a variable (usually small) conductive component. The sensorineural component of the hearing loss is slowly progressive. It is typically in the mild range (20 to 40 dB hearing level) during early childhood and progresses to the moderate hearing loss range (40 to 60 dB hearing level) by early adulthood. We present a description of the otologic manifestations and an analysis of audiologic findings in six members of a family with Townes-Brocks syndrome.