Acute Otitis Media with Effusion

Acute otitis media with effusion is the presence of fluid in the middle ear behind an intact tympanic membrane, without signs of acute infection (no fever, no ear pain, and a drum that is neither bulging nor inflamed), and it commonly follows an acute ear infection or upper respiratory tract infection.

• Eustachian tube dysfunction is the cause, which is more likely in young children whose tubes are short, horizontal and narrow.
• Up to 90 percent of children have an episode of effusion before school age, and most resolve within 3 months. About 5 to 10 percent last beyond 1 year.
• Risk factors: age under 5 years, upper respiratory infection, adenoid hypertrophy, cleft palate, Down syndrome, smoking exposure, daycare attendance, bottle feeding supine and allergy.
• Persistence beyond 3 months is defined as chronic otitis media with effusion.

The ear feels blocked, with hearing loss.

• Hearing loss (conductive, mild to moderate), blocked or full ear feeling, and speech or attention problems.
• Ear tugging, balance problems and clumsiness in young children.
• Little pain or fever.
• Otoscopy: dull, retracted or neutral drum with reduced mobility, air-fluid level or bubbles, and an amber or grey colour.
• Differential diagnosis: acute otitis media, eustachian tube dysfunction without effusion, tympanosclerosis, cholesteatoma, sensorineural hearing loss, nasopharyngeal mass, and adhesive otitis media.
• Complications: conductive hearing loss, speech and language delay, behaviour and educational problems, tympanic membrane retraction, cholesteatoma, ossicular erosion and recurrent acute otitis media.

Diagnosis is by pneumatic otoscopy and tympanometry.

• Pneumatic otoscopy: reduced or absent drum movement.
• Tympanometry: flat (type B) trace or negative pressure (type C).
• Audiometry (pure tone in older children; visual reinforcement or play audiometry in younger): mild to moderate conductive loss (20 to 40 dB).
• Examine the nose, nasopharynx and palate. In adults with unilateral effusion, flexible nasendoscopy is needed to examine the nasopharynx.
• Unilateral persistent effusion in an adult needs nasopharyngeal examination to exclude a tumour.

Watchful waiting is the first step.

• Supportive: observe for 3 months from onset. Avoid smoke exposure. Educate parents and teachers about hearing loss (seat child in front of the class, speak clearly). Encourage autoinflation (blowing against closed nose) in older children.
• Pharmacological: antihistamines, decongestants, antibiotics and oral steroids are not recommended for effusion. Intranasal corticosteroid (mometasone 50 micrograms per nostril once daily) may be used for associated allergic rhinitis or adenoid hypertrophy.
• Procedures: for effusion persisting beyond 3 months with hearing loss of 25 to 30 dB or more, or speech delay: grommets (tympanostomy tubes), with or without adenoidectomy in children over 3 to 4 years or with significant adenoid symptoms. Hearing aids if surgery is declined or not suitable.
• Special groups: children with Down syndrome, cleft palate or developmental delay need early audiological assessment and lower threshold for tubes.
• Red flags: pain, fever, otorrhoea, vertigo, facial weakness, retraction pocket, unilateral effusion in an adult, and speech delay.
• Follow-up: repeat audiometry and tympanometry at 3 months. After grommets, review at 4 to 6 weeks and every 6 months until extrusion.