Acute middle ear infection with effusion and signs of inflammation, most common in young children.
Also known as: AOM, middle ear infection, ear infection, suppurative otitis media
Overview
Acute infection of the middle ear cleft characterized by middle ear effusion (MEE) plus rapid onset of signs and symptoms of middle ear inflammation. Distinguished from otitis media with effusion (OME), which lacks acute inflammatory signs.
Epidemiology
Most common bacterial infection of childhood; peak incidence 6-24 months. By age 3, ~80% of children have had at least one episode. Risk highest in fall/winter following viral URI.
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Absence of breastfeeding (breastfeeding ≥6 months is protective)
Craniofacial anomalies (cleft palate, Down syndrome)
Family history of recurrent AOM
Native American, Alaskan Native, and Australian Aboriginal ancestry
Pathophysiology
Viral URI causes eustachian tube dysfunction and mucosal edema, impairing middle ear drainage. Negative pressure draws nasopharyngeal secretions retrograde into the middle ear, where bacterial pathogens proliferate in the resulting effusion. Common bacterial pathogens: Streptococcus pneumoniae, non-typeable Haemophilus influenzae, Moraxella catarrhalis. Viruses (RSV, rhinovirus) may be the sole pathogen.
Clinical presentation
Symptoms
Ear pain (otalgia) — pulling/tugging at ear in preverbal children
In older children/adults: localized pain, sensation of ear fullness
Signs / physical exam
Bulging tympanic membrane — most specific sign
Loss of bony landmarks; opacification; yellow, white, or hemorrhagic color
Impaired TM mobility on pneumatic otoscopy
Air-fluid level or bubbles behind TM
Otorrhea through a perforation
Classic findings
Bulging, opacified TM with impaired mobility on pneumatic otoscopy in a febrile child with otalgia.
Differential diagnosis
Otitis media with effusion (OME) — Middle ear effusion without acute inflammatory signs; usually painless; hearing loss; no fever; observation appropriate
Otitis externa — Pain on tragal pressure or pinna traction, erythematous swollen canal with debris, normal TM if visible; treat with topical otic drops
Bullous myringitis — Painful bullae on TM; classically Mycoplasma but most often pneumococcus; treat as AOM
Mastoiditis — Postauricular erythema, swelling, fluctuance, protruding auricle, fever; CT temporal bone confirms; IV antibiotics ± surgical drainage
Foreign body in ear canal — Unilateral pain or discharge, often in toddlers; direct visualization; removal under microscopy
Dental pain referred — Posterior molar caries can refer pain to ear; normal otoscopy
TMJ dysfunction — Preauricular pain, clicking with jaw motion, normal TM
Diagnostic workup
Diagnostic criteria
AAP 2013: (1) Moderate-to-severe bulging of TM or new-onset otorrhea not due to otitis externa, OR (2) mild bulging with recent (<48 h) onset of ear pain or intense erythema of TM. Middle ear effusion must be present.
Labs
AOM is a clinical diagnosis; laboratory testing is rarely needed
Tympanocentesis with culture reserved for treatment failure, immunocompromised, or neonates
Imaging
Pneumatic otoscopy or tympanometry — confirms middle ear effusion when otoscopy ambiguous
CT temporal bone if mastoiditis, intracranial complication, or cholesteatoma suspected
Diagnostic algorithm
Age / Severity
Antibiotic Decision
Preferred Agent
<6 months, any severity
Antibiotics always
Amoxicillin or amox-clav
6-23 months, bilateral or severe
Antibiotics always
Amoxicillin 80-90 mg/kg/day
6-23 months, unilateral non-severe
Antibiotics OR 48-72 h observation
Amoxicillin if treating
≥24 months, severe (T≥39, severe pain, otorrhea)
Antibiotics always
Amoxicillin or amox-clav
≥24 months, non-severe
Antibiotics OR observation with follow-up
Amoxicillin if treating
Any age, treatment failure at 48-72 h
Switch antibiotic
Amoxicillin-clavulanate or ceftriaxone IM
AAP 2013 management algorithm for acute otitis media by age, severity, and treatment response.
Treatment
First-line
Amoxicillin 80-90 mg/kg/day divided BID × 10 days (5-7 days if age ≥6 y and non-severe) — preferred if no amoxicillin in prior 30 days, no concurrent purulent conjunctivitis, and no history of recurrent AOM unresponsive to amoxicillin
Amoxicillin-clavulanate 90 mg/kg/day amoxicillin component if any of the above risk factors are present, or for treatment failure at 48-72 h
Analgesia: acetaminophen or ibuprofen — addressed independently of antibiotic decision
Observation option (deferred antibiotics, reassess 48-72 h) for non-severe AOM in children ≥6 months without otorrhea — requires reliable follow-up
Second-line / adjunct
Cefdinir, cefuroxime, or cefpodoxime for non-anaphylactic penicillin allergy
Azithromycin or clindamycin for severe penicillin allergy (high resistance — use only when alternatives unavailable)
Ceftriaxone IM 50 mg/kg daily × 1-3 days for vomiting or oral intolerance
Tympanostomy tubes if ≥3 episodes in 6 months, ≥4 in 12 months, or persistent OME with hearing loss
Complications
TM perforation (usually heals spontaneously)
Mastoiditis — postauricular swelling, requires IV antibiotics ± mastoidectomy
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