[One case report of Mohr-Tranebjærg syndrome].

A 4-year-old male patient was found poor development in hearing and speech, without family hereditary history. Hearing screening was failed at birth. From the age of 2, the patient showed poor response to sound and speech, but no audiological examination was carried out. After physical examination, no deformity was found in both ears, and the tympanic membranes were intact; the muscular tension was normal; and the visual acuity was normal. The acoustic immittance showed curve A; DPOAE showed that both ears passed; click ABR threshold was greater than 95 dB nHL, bone conduction was greater than 45 dB nHL; electrocochleogram was bilateral elicited. There were no malformations of cochlea and inner ear showed in temporal bone CT and internal auditory canal MRI. Gene detection indicated a mutation in TIMM8A gene of X chromosome. Combined with the patient's medical history, gene detection, audiological manifestations and imaging examination, the final diagnosis was Mohr-Tranebjærg syndrome, bilateral severe sensorineural hearing loss, and auditory neuropathy.