Acute otitis media
Infection of the middle ear that follows failure of the Eustachian tube to ventilate and drain it, so the same self-limiting process that causes glue ear can also cause a painful, bulging, infected drum.
In a nutshell
A blocked Eustachian tube, usually from viral URTI-related mucosal swelling, traps secretions in the middle ear that nasopharyngeal bacteria then infect. Rising pressure against the closed drum causes the pain and the bulging appearance, and the same self-limiting mechanism explains why most cases resolve without antibiotics.
Classic presentation
A young child with a preceding cold who develops sudden ear pain and fever, with a red, bulging drum on otoscopy.
Key points
- The Eustachian tube is short, floppy and horizontal in young children, which is why they get acute otitis media so much more often than adults.
- Pain and bulging come from rising pressure in a closed middle-ear space; if the drum perforates, pain classically eases as pressure is released.
- Most infections are self-limiting and resolve without antibiotics within a few days, so analgesia and safety-netting (or a delayed prescription) is the default.
- Immediate antibiotics are reserved for systemic illness, bilateral disease under 2 years, perforation with discharge, or significant comorbidity.
- Mastoiditis presents with postauricular swelling, tenderness and a protruding ear, and reflects infection tracking into the adjacent mastoid air cells.
First-line investigation
Otoscopy: acute otitis media is a clinical diagnosis made by direct visualisation of a red, bulging tympanic membrane.
First-line management
Analgesia and safety-netting, with a delayed antibiotic prescription if symptoms do not settle; immediate antibiotics only in higher-risk groups.
Exam traps
- A red ear alone is not diagnostic; bulging with loss of the light reflex is the key discriminating sign, since redness alone can occur with crying or fever.
- Sudden relief of pain with new discharge suggests perforation, not resolution of infection.
- Postauricular swelling and a protruding ear is mastoiditis until proven otherwise and needs urgent assessment, not routine antibiotics alone.
Educational content pending clinical review. Not medical advice.