Granular Myringitis

Granular myringitis is chronic inflammation of the outer layer of the tympanic membrane with replacement of the epithelium by granulation tissue, causing persistent painless or mildly uncomfortable otorrhoea. The middle ear is normal and the drum is usually intact.

It is uncommon, affects adults more than children, and is often seen after trauma to the canal (cotton buds, water entering the ear) or recurrent otitis externa. Bacterial overgrowth with Pseudomonas aeruginosa and Staphylococcus aureus is frequent.

Pathophysiology.

Loss of the epithelial layer exposes the underlying fibrous layer to infection and chronic inflammation. Granulation tissue forms and sheds a purulent discharge, and healing is poor while the infection and moisture persist.

Chronic ear discharge (mucoid or purulent), itching, a sense of fullness and mild discomfort. Hearing is normal or mildly reduced. There is no fever.

Red flags.

• Pain out of proportion with granulation in the canal in a diabetic or immunocompromised patient (malignant otitis externa).
• Facial weakness.
• Bloody discharge with a canal mass.

Examination under the microscope shows red granular patches on the lateral surface of the drum with an intact drum and a normal middle ear. Swab for culture. Audiometry is done when hearing is reduced. Biopsy a lesion that does not heal or has an unusual appearance to exclude malignancy.

Differential diagnosis.

• Chronic suppurative otitis media with perforation.
• Cholesteatoma.
• Chronic otitis externa.
• Fungal otitis externa (otomycosis).
• Squamous cell carcinoma of the ear canal.
• Granulomatosis with polyangiitis and tuberculosis.

Clean the ear by microsuction, keep it dry, and treat with topical antimicrobial and steroid drops. Cauterise persistent granulations with silver nitrate under the microscope. Refer if there is no response after 2 to 3 weeks.

• Ciprofloxacin 0.3% with dexamethasone 0.1% ear drops: 4 drops into the affected ear twice daily for 7 to 10 days; maximum 10 days; monitor for local irritation and fungal overgrowth; no systemic adjustment; the dose is the same in children over 1 year.
• Silver nitrate cautery (applicator) to granulations: once, repeated every 1 to 2 weeks for up to 3 treatments; avoid contact with normal skin; monitor for pain and canal stenosis.

Treat fungal overgrowth with clotrimazole 1% ear drops, 4 to 5 drops twice daily for 14 days.

Monitoring. Examine weekly until healed, then at 4 to 6 weeks.

Referral and escalation. ENT for persistent or recurrent disease, or when biopsy is needed.