A newborn fails the automated ABR (AABR) screening. On diagnostic click-evoked ABR at 3 months, wave I is present but wave V is absent. What is the MOST likely diagnosis?
- A Bilateral profound sensorineural hearing loss (cochlear origin)
- B Auditory neuropathy spectrum disorder (ANSD) ✓
- C Bilateral conductive hearing loss due to middle ear effusion
- D Cortical deafness due to bilateral auditory cortex lesions
Correct answer: B. Auditory neuropathy spectrum disorder (ANSD)
Explanation
Auditory neuropathy spectrum disorder (ANSD) is characterized by present cochlear function (normal OAEs and present wave I, reflecting cochlear outer hair cell activity) but absent or highly abnormal wave V on ABR, reflecting disruption of neural synchrony at the cochlear nerve or brainstem level. In classic cochlear SNHL, both OAEs and ABR waves are absent. Conductive loss would elevate thresholds uniformly; cortical deafness would show normal peripheral ABR waves with absent cortical responses.
Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.