Cholesteatoma
Definition and clinical importance
Cholesteatoma is an acquired (mostly) or congenital collection of keratinising squamous epithelium within the middle ear and/or mastoid air cells.
It is not neoplastic but behaves aggressively: the lesion produces proteolytic and osteolytic enzymes, erodes bone and middle‑ear structures and, if untreated, causes progressive conductive (and sometimes mixed) hearing loss and potentially life‑threatening local or intracranial complications.
Emergency clinicians must recognise likely cases, identify red flags that require urgent ENT review, initiate appropriate immediate measures and avoid interventions that increase harm.
Pathophysiology
- Most acquired cholesteatomas arise from tympanic‑membrane retraction pockets (often after Eustachian tube dysfunction) that trap squamous epithelium and keratin debris.
- The active basal layer generates enzymes and inflammatory mediators that destroy ossicles and surrounding bone (mastoid, tegmen) and can involve the labyrinth or facial nerve canal.
- Spread may lead to mastoiditis, labyrinthine fistula, facial nerve palsy, meningitis, brain abscess or lateral sinus thrombosis.
Typical presentation
- Chronic or recurrent foul‑smelling unilateral otorrhoea (often intermittent).
- Progressive unilateral or asymmetric hearing loss - usually conductive; becomes mixed if inner ear is involved.
- Aural fullness, intermittent otalgia; vestibular symptoms (vertigo) if the labyrinth is affected.