Acute Otitis Media (AOM)
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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Risk factors
- Age <2 years (short, horizontal eustachian tube)
- Daycare attendance, exposure to tobacco smoke
- Bottle-propping, pacifier use beyond 6 months
- 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
- Fever, irritability, poor feeding, disrupted sleep
- Preceding URI symptoms (rhinorrhea, cough)
- Hearing loss; otorrhea if TM has perforated
- 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 |
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
- Intracranial: meningitis, brain abscess, lateral sinus thrombosis
- Cholesteatoma from chronic perforation or retraction pocket
- Conductive hearing loss with speech/language delay if persistent effusion
- Facial nerve palsy (rare, traverses middle ear)
PANCE pearls
- Bulging TM is the single most important finding — erythema alone is nonspecific (crying can cause it).
- AOM in any child <6 months → always treat with antibiotics. Ages 6-24 months: treat if bilateral, severe, or otorrhea; otherwise observation option.
- Concurrent purulent conjunctivitis suggests non-typeable H. influenzae → use amoxicillin-clavulanate.
- PCV13/PCV15/PCV20 vaccination has shifted pathogen epidemiology — H. influenzae now equals or exceeds S. pneumoniae in many settings.
- Recurrent AOM = ≥3 episodes in 6 months or ≥4 in 12 months — tympanostomy tube referral indicated.
References
- AAP 2013 — Lieberthal AS et al. The diagnosis and management of acute otitis media. Pediatrics 2013;131(3):e964-e999
- AAO-HNS 2022 — Rosenfeld RM et al. Clinical Practice Guideline: Tympanostomy Tubes in Children (Update). Otolaryngol Head Neck Surg 2022
- AAFP — Coker TR et al. Diagnosis, microbial epidemiology, and antibiotic treatment of acute otitis media in children: a systematic review. JAMA 2010
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