Auditory dysfunction in Stickler syndrome

Area of Science:

• Genetics and Audiology
• Ophthalmology

Background:

• Stickler syndrome (hereditary progressive arthro-ophthalmopathy) is a genetic disorder affecting connective tissues.
• Hearing loss is a known manifestation, but its characteristics and diagnostic utility require further investigation.

Purpose of the Study:

• To characterize the hearing loss in Stickler syndrome.
• To explore potential mechanisms of hearing impairment.
• To assess the auditory phenotype's value in differential diagnosis.

Main Methods:

• A multifamily study involving 46 individuals from 29 families with Stickler syndrome.
• Comprehensive audiological and otolaryngological examinations, including audiometry and immittance testing.
• Advanced tests like otoacoustic emissions, auditory brainstem response, and temporal bone CT on a subset of participants.

Main Results:

• Adults most commonly exhibited mild, high-frequency sensorineural hearing loss, similar to age-related changes.
• Hypermobile middle ear systems (Type A(D) tympanograms) were identified in 46% of affected individuals.
• No inner ear malformations were detected via CT scans.

Conclusions:

• Hypermobile middle ear systems are a novel diagnostic feature for Stickler syndrome.
• The mild, non-progressive sensorineural hearing loss in type I Stickler syndrome differs from types II and III, aiding differential diagnosis.
• Auditory findings, particularly middle ear system characteristics, are valuable for diagnosing Stickler syndrome and related disorders.