Infectious Ear Diseases: Key Facts and Management

Anatomical Classification and Pathophysiology

Ear infections are classified based on the anatomical location affected: external ear (otitis externa), middle ear (otitis media), or inner ear (labyrinthitis) 1, 2
The external ear consists of the auricle (pinna) and ear canal, separated from the middle ear by the tympanic membrane 3
The middle ear comprises the middle ear cavity and ossicles (malleus, incus, stapes), connected to the nasopharynx by the Eustachian tube 3
The inner ear contains the semicircular ducts and cochlea, connected to the middle ear via the oval window 3

Infection of the skin and subcutaneous tissue of the external ear canal, often involving the auricle 2
Symptoms include ear pain, tenderness with manipulation of the tragus or pinna, itching, canal edema, erythema, and otorrhea 1, 2
Primary pathogens include Pseudomonas aeruginosa and Staphylococcus aureus 2
Topical antibiotics are the mainstay of treatment for uncomplicated cases 1
Aural toilet (cleaning) is necessary when the ear canal is obstructed 1

Bacterial infection of the middle ear, often following viral upper respiratory tract infection 4, 5
Peak incidence in children 6-47 months of age 3
Symptoms include sudden onset of ear pain, fever, irritability, and possible otorrhea 2
Moderate-to-severe bulging of the tympanic membrane or mild bulging with recent onset of ear pain is diagnostic 3
Pain assessment and management is essential 1
Symptomatic management is the mainstay for most cases 4
Antibiotics reserved for children with severe, persistent, or recurrent infections 4

Characterized by fluid in the middle ear without signs or symptoms of acute infection 3
Often occurs after AOM when inflammation resolves but middle ear fluid persists 2
Eustachian tube dysfunction prevents normal aeration and fluid drainage 4
Watchful waiting is the primary approach 4
Ventilation (tympanostomy) tubes primarily for children with chronic effusions and hearing loss, developmental delays, or learning difficulties 4

Chronic inflammation of the middle ear and mastoid mucosa with non-intact tympanic membrane 3
Persistent infection through perforated tympanic membrane or ventilation tube 3
Symptoms include persistent ear discharge through a perforated tympanic membrane, hearing loss 3, 2
Aural toilet to remove discharge and debris is necessary 1
Surgical intervention may be required for cases unresponsive to medical management 4

Location of pain/tenderness and pneumatic otoscopy are crucial for differentiating between otitis externa and otitis media 1
Otitis externa can mimic acute otitis media due to erythema involving the tympanic membrane 1
Necrotizing otitis externa is an aggressive infection requiring urgent attention 1
Reassessment is necessary if symptoms don't improve within 48-72 hours for both otitis externa and otitis media 1