Pediatric audiologic profile in type 1 and type 2 neurofibromatosis.

The neurofibromatoses with two subclasses known as NF1 and NF2 are two genetically distinct, autosomal dominantly inherited conditions with significant ramifications in the human auditory system. NF1 is a multisystem progressive disorder that can frequently involve portions of the auditory system in diverse and subtle ways and in which no characteristic audiologic findings can be discerned. NF2 is characterized by the presence of bilateral vestibular schwannomas, sometimes associated with multiple intracranial and spinal tumors. In 43 children with NF1, significant auditory system involvement was found by pure-tone, immittance, and auditory brainstem response (ABR) evaluation. Indications are that audiologists need to contribute to the diagnosis and management in this condition. In 13 children with NF2, handicapping hearing loss was not the primary or usual presenting symptom. However, current findings suggest that ABR and acoustic reflex studies are always indicated in the pediatric NF2 population and are as valid and significant as in adults with NF2.