What are the different types of ear infections and their treatments?

Types of Ear Infections and Their Treatments

The three main types of ear infections are acute otitis media (middle ear infection), otitis media with effusion (fluid in the middle ear), and acute otitis externa (outer ear infection or "swimmer's ear"), each requiring different treatment approaches based on location, causative pathogens, and patient factors.

Middle Ear Infections (Otitis Media)

Acute Otitis Media (AOM)

• Definition: Rapid onset inflammation of the middle ear with signs and symptoms of middle ear inflammation 1
• Common symptoms: Otalgia (ear pain), fever, irritability, hearing loss 2
• Diagnostic criteria:
  • Moderate-to-severe bulging of tympanic membrane or new onset otorrhea not from otitis externa
  • Mild bulging of tympanic membrane with recent onset ear pain or intense erythema 1
• Causative pathogens:
  • Streptococcus pneumoniae (most common, ~33% of cases)
  • Haemophilus influenzae (20-30%, mostly non-typable)
  • Moraxella catarrhalis (7-20%) 1
  • Almost always preceded by viral upper respiratory tract infection 1
• Treatment:
  • First-line: Amoxicillin (40-45 mg/kg/day in divided doses) for 10 days 2
  • Alternative options (for penicillin allergy or recent amoxicillin use):
    • Amoxicillin-clavulanate
    • Cefuroxime
    • Ceftriaxone
  • Watchful waiting may be appropriate in children ≥6 months with uncomplicated unilateral AOM 2

Otitis Media with Effusion (OME)

• Definition: Fluid in the middle ear without signs or symptoms of acute ear infection 1
• Symptoms: Often asymptomatic, may have fullness sensation or mild hearing loss
• Treatment:
  • Usually resolves spontaneously within 3 months
  • No antibiotics unless persistent beyond 3 months with hearing loss
  • Tympanostomy tube placement for chronic OME (persisting ≥3 months) 2

Recurrent Acute Otitis Media

• Definition: Three or more well-documented episodes in 6 months or four or more episodes in 12 months with at least one in past 6 months 1
• Treatment:
  • Tympanostomy tubes may be indicated 2
  • Prophylactic antibiotics generally not recommended

External Ear Infections (Otitis Externa)

Acute Otitis Externa (AOE)

• Definition: Diffuse inflammation of the external ear canal, often with rapid onset (within 48 hours) in the past 3 weeks 1
• Symptoms:
  • Otalgia (often severe), itching, fullness
  • Tenderness of tragus/pinna (hallmark sign)
  • Ear canal edema, erythema, sometimes otorrhea 1
• Causative pathogens:
  • Pseudomonas aeruginosa (20-60%)
  • Staphylococcus aureus (10-70%)
  • Often polymicrobial 1
• Treatment:
  • First-line: Topical fluoroquinolone eardrops (ciprofloxacin 0.2% or ofloxacin 0.3%) twice daily for 7 days 3
    • For adults and children ≥13 years: 10 drops
    • For children <13 years: 5 drops 4, 5
  • Gentle cleaning of ear canal debris before medication
  • Pain management with acetaminophen or NSAIDs; severe pain may require short-term opioids 3
  • Oral antibiotics NOT recommended unless:
    • Diabetes mellitus
    • Immunocompromised state
    • Extension beyond ear canal
    • Concurrent cellulitis 3

Fungal Otitis Externa

• Characteristics: Characteristic appearance of debris in ear canal
• Risk factors: Diabetes, immunocompromised state, long-term topical antibiotic use
• Treatment:
  • Gentle debridement
  • Topical antifungal therapy 3

Necrotizing (Malignant) Otitis Externa

• Definition: Aggressive infection invading deeper structures
• Risk factors: Diabetes, immunocompromised state
• Treatment:
  • Hospitalization
  • Parenteral antipseudomonal antibiotics
  • Surgical debridement if needed
  • ENT referral 3

Special Considerations

Ciprofloxacin-Resistant Infections

• Increasing prevalence (4.5% of otorrhea cases)
• Common resistant organisms: MRSA (33%), Corynebacterium striatum (19%)
• Topical ciprofloxacin alone ineffective (2.7% success rate)
• Better options:
  • Ciprofloxacin plus oral antibiotics (64.7% success)
  • Non-ciprofloxacin topical therapy (70% success) 6

Tympanostomy Tubes

• Most common ambulatory surgery for children in the US
• Indications:
  • Recurrent AOM
  • Persistent AOM
  • Chronic OME with hearing loss 2

Prevention of Recurrent Ear Infections

• Keep ears dry
• Use ear protection when showering/swimming
• Avoid cleaning ear canal with cotton-tip applicators 3

Pitfalls to Avoid

1. Misdiagnosis: Ensure proper visualization of tympanic membrane; pneumatic otoscopy helps distinguish AOM from OME
2. Inappropriate antibiotic use: Avoid oral antibiotics for uncomplicated AOE
3. Inadequate pain management: Ear pain can be severe and requires appropriate analgesia
4. Missing complications: Watch for signs of extension beyond the ear canal
5. Ciprofloxacin resistance: Consider alternative therapy if not responding to initial treatment

By correctly identifying the type of ear infection and following evidence-based treatment guidelines, most ear infections can be effectively managed with minimal complications.