Auditory phenotype of Smith-Lemli-Opitz syndrome

Area of Science:

• Genetics
• Audiology
• Developmental Pediatrics

Background:

• Smith-Lemli-Opitz syndrome (SLOS) is a genetic disorder caused by DHCR7 variants, leading to congenital malformations and intellectual disability.
• Auditory characteristics in SLOS patients are poorly understood, with limited data from case reports.

Purpose of the Study:

• To systematically investigate and describe the auditory phenotype in individuals with Smith-Lemli-Opitz syndrome.
• To characterize the prevalence and types of hearing loss and auditory pathway dysfunction in SLOS.

Main Methods:

• Conducted age- and ability-appropriate hearing evaluations on 32 patients with SLOS.
• Utilized auditory brainstem response (ABR) testing on 21 patients to assess the auditory neural pathway.
• Employed objective assessment methods for patients with behavioral testing difficulties.

Main Results:

• Peripheral or retrocochlear auditory dysfunction was present in 65.6% of the SLOS cohort.
• A heterogeneous audiometric profile was observed, including conductive, mixed, and sensorineural hearing loss.
• Abnormal ABRs, indicating retrocochlear dysfunction, were found in 21.9% of patients.

Conclusions:

• Individuals with SLOS frequently experience hearing loss, impacting communication, speech, and language development.
• Routine audiological surveillance is recommended for early detection and management of hearing impairments in SLOS patients.