Chronic suppurative otitis media (CSOM)

Types

1. Mucosal CSOM
   • Active mucosal disease: perforation with otorrhoea, inflamed middle-ear mucosa, and sometimes granulations/aural polyp.
   • Inactive mucosal disease: dry, permanent pars tensa perforation without active inflammation.
   • Usually corresponds to the older term tubotympanic or “safe” disease, but no chronic ear disease should be assumed entirely safe.
2. Squamous epithelial disease (cholesteatoma)
   • Keratinizing squamous epithelium in the middle ear/mastoid, commonly arising from an attic or marginal retraction pocket.
   • May erode ossicles, labyrinth, facial canal, or intracranial boundaries.
   • Historically called atticoantral or “unsafe” CSOM.

Causes and risk factors

• Recurrent or inadequately resolved acute otitis media
• Persistent Eustachian-tube dysfunction
• Tympanic membrane perforation following infection or trauma
• Poor access to health care, overcrowding, malnutrition, and recurrent upper respiratory infections
• Cleft palate or craniofacial anomalies
• Water entering the ear through a perforation
• Cholesteatoma

Clinical features

• Persistent or recurrent foul-smelling or mucoid/purulent ear discharge
• Conductive hearing loss, often fluctuating
• Tinnitus or a blocked-ear sensation
• Usually little pain in uncomplicated mucosal disease
• Otoscopy may show:
  • Central, marginal, or attic perforation
  • Mucopus in the canal/middle ear
  • Granulation tissue or polyp
  • Retraction pocket, keratin debris, or attic crust suggesting cholesteatoma

Red flags requiring urgent ENT assessment

• Severe or increasing otalgia
• Vertigo, spontaneous nystagmus, or sudden worsening hearing
• Facial weakness
• Post-auricular swelling/tenderness or fever
• Severe headache, neck stiffness, altered consciousness, focal neurological signs
• Aural polyp, marginal/attic perforation, or keratin debris suspicious for cholesteatoma

Complications

• Mastoiditis
• Ossicular erosion and conductive hearing loss
• Labyrinthitis and sensorineural hearing loss
• Facial nerve palsy
• Petrositis
• Labyrinthine fistula

• Meningitis
• Extradural abscess
• Subdural empyema
• Brain abscess
• Lateral/sigmoid sinus thrombosis

Diagnosis

• Otoscopy or preferably microscopic ear examination
• Suction clearance of debris/discharge, where available
• Hearing assessment: pure-tone audiometry
• Ear swab culture if disease is persistent, recurrent, severe, or unresponsive to initial therapy
• High-resolution CT temporal bone if cholesteatoma, bony erosion, complication, or surgical planning is suspected
• MRI when intracranial extension or labyrinthine/soft-tissue complications are suspected

Management principles

1. Aural toilet
   • Careful dry mopping or microsuction to clear discharge and debris.
   • Keep the ear dry. Avoid swimming and prevent water entry during bathing.
2. Topical antibiotic ear drops
   • Topical quinolone drops are commonly preferred when there is a perforation because they cover common gram-negative organisms including Pseudomonas and avoid the ototoxicity concern of aminoglycoside-containing drops.
   • Choice and duration should be individualized by a clinician, particularly for children, pregnancy, recurrent disease, or suspected fungal infection.
3. Treat contributing nasal/Eustachian-tube disease
   • Address allergic rhinitis, chronic rhinosinusitis, adenoid disease, or recurrent upper respiratory infections when relevant.
4. Systemic antibiotics
   • Not routinely required for uncomplicated CSOM.
   • Considered for systemic illness, spreading infection, mastoiditis, or other complications, guided by clinical assessment and culture where possible.
5. Surgery
   • Tympanoplasty/myringoplasty: closes a persistent perforation and may improve hearing after infection is controlled.
   • Mastoidectomy with tympanoplasty: used selectively, especially for cholesteatoma, complications, or persistent/refractory disease.
   • Cholesteatoma requires surgical assessment, since drops do not eradicate the keratinizing lesion.

Prevention and patient advice

• Complete prescribed therapy and attend follow-up until the ear is dry.
• Keep water out of the affected ear.
• Do not insert cotton buds, oils, or unprescribed drops into the ear.
• Obtain a hearing test in persistent or recurrent disease, especially in children because hearing loss may affect speech, learning, and development.
• Seek urgent care for the red-flag symptoms above.