Ossicular discontinuity and exostoses in Proteus syndrome: a case report

Proteus syndrome (PS) is a rare hamartomatous disorder characterized by mosaic overgrowth of multiple tissues that manifests early in life and is progressive. The presence of unilateral external auditory canal exostoses in a patient who is not a swimmer or surfer is suggestive of PS. However, hearing loss is not a typical feature. Here, we describe exostoses and ossicular discontinuity with conductive hearing loss in a patient with PS. The treatment consisted of canalplasty and ossicular chain reconstruction. A postoperative reduction was demonstrated in the patient's air-bone gap, from 21 dB to 13 dB for the pure tone average (four frequencies) and from 41 dB to 15 dB in the high-frequency range (6,000 to 8,000 Hz). Causes of ossicular discontinuity are discussed. Routine annual audiometric and otolaryngological evaluation should be considered in all patients with temporal bone involvement of PS.