Most common type of hearing loss in TB otitis media
**Core Concept**
TB otitis media, a form of otitis media caused by tuberculosis infection, can lead to hearing loss due to the destruction of the middle ear structures. The most common type of hearing loss in TB otitis media is conductive hearing loss, resulting from the damage to the ossicular chain and the tympanic membrane.
**Why the Correct Answer is Right**
Conductive hearing loss occurs when there is a problem with the conduction of sound waves through the middle ear. In TB otitis media, the infection causes caseation necrosis and granuloma formation, leading to the destruction of the ossicles, particularly the malleus and incus. This damage disrupts the normal conduction of sound waves, resulting in conductive hearing loss. The tympanic membrane may also be affected, further contributing to the hearing loss.
**Why Each Wrong Option is Incorrect**
* **Option A:** Sensorineural hearing loss is less common in TB otitis media, as it typically affects the middle ear structures rather than the inner ear.
* **Option B:** Mixed hearing loss occurs when both conductive and sensorineural components are present. While possible in TB otitis media, it is not the most common type of hearing loss.
* **Option D:** Central hearing loss is not typically associated with TB otitis media, as it involves the auditory pathways in the brain rather than the middle ear.
**Clinical Pearl / High-Yield Fact**
TB otitis media is a rare but serious complication of tuberculosis infection, often presenting with a long history of otalgia and hearing loss. It is essential to consider TB otitis media in the differential diagnosis of chronic otitis media, particularly in patients with a history of tuberculosis.
**Correct Answer:** C. Conductive hearing loss