External Otitis — Causes, Symptoms and Treatment

What is otitis externa?

Otitis externa is an infection or inflammation of the skin of the external auditory canal (ear canal), commonly known as "swimmer's ear." It affects children and adults, with an increased incidence during the warm season, when contact with water is more frequent.

The external auditory canal is a delicate structure, protected by cerumen (earwax) and normal bacterial flora. The destruction of these protective barriers creates favorable conditions for infection.

Symptoms

• Ear pain (otalgia) — intense, worsened by pulling on the pinna or pressing on the tragus
• Auricular pruritus — itching in the ear canal, often the initial symptom
• Otorrhea — ear discharge, initially serous, then purulent
• Sensation of ear fullness — due to swelling of the canal walls
• Hearing loss — due to obstruction of the canal with secretions and edema
• Swelling and redness — of the external auditory canal and sometimes of the pinna
• Pain during chewing — due to the proximity of the temporomandibular joint
• Preauricular or retroauricular lymphadenopathy

Unlike acute otitis media, otitis externa does not cause fever (except in severe forms) and the pain is triggered by movement of the pinna.

Causes

Infectious causes

• Pseudomonas aeruginosa — the most common bacterial agent
• Staphylococcus aureus
• Fungal infections — Aspergillus, Candida (otomycosis) — especially in warm-humid climates or after prolonged antibiotic therapy

Predisposing factors

• Chronic moisture — frequent swimming, diving, excessive sweating
• Local trauma — aggressive use of cotton swabs, inserting fingers or objects into the ear canal
• Absence of protective cerumen — due to excessive cleaning
• Auricular devices — headphones, hearing aids, ear plugs
• Dermatitis — eczema, seborrheic dermatitis, psoriasis
• Narrow ear canals — anatomical predisposition

Diagnosis

• ENT clinical examination — pain on pulling the pinna (tragus sign), edema and erythema of the external auditory canal
• Otoscopy — edematous canal with secretions and debris; the eardrum is usually normal (if it can be visualized)
• Otomicroscopy with aspiration of secretions — essential for canal debridement and visualization of the eardrum
• Culture of secretions — in treatment-resistant or recurrent forms

The tragus sign — pain when pressing on the tragus (the cartilage in front of the ear canal) — is a simple and specific test for otitis externa, which differentiates it from otitis media.

Treatment

General principles

• Ear canal debridement — aspiration of secretions under otomicroscopic guidance, essential for the efficacy of topical treatment
• Avoiding contact with water — protecting the ear during treatment

Topical treatment (first-line)

• Otic drops with antibiotic + corticosteroid — ciprofloxacin/dexamethasone or ofloxacin — usually 7-10 days
• Acetic acid otic drops — acidify the environment, creating conditions unfavorable to bacteria
• Topical antifungals — in otomycosis (topical clotrimazole)
• Ear wick — in cases of severe edema preventing drop penetration

Systemic treatment

• Analgesics — paracetamol or ibuprofen
• Oral antibiotics — only in severe forms with cellulitis or fever

Prevention

• Drying the ears after swimming — tilting the head, using a hair dryer from a distance
• Preventive drops of diluted acetic acid or isopropyl alcohol after swimming
• Avoiding cotton swabs and inserting objects into the ear
• Using waterproof ear plugs when swimming (for children with predisposition)
• Treating associated auricular dermatitis

When to see a doctor

• Persistent or worsening ear pain
• Abundant ear discharge
• Swelling or redness extending to the pinna or periauricular tissues
• Associated fever
• Symptoms do not improve after 48 hours of topical treatment
• Recurrent episodes of otitis externa

Complications

• Auricular cellulitis — extension of infection to the pinna and periauricular soft tissues
• Auricular abscess — requires surgical drainage
• Ear canal stenosis — in chronic recurrent otitis externa
• Necrotizing (malignant) otitis externa — an extremely serious complication in immunocompromised or diabetic patients, rare in children
• Myringitis — associated eardrum inflammation
• Chronic otomycosis — due to inadequate or prolonged topical antibiotic treatment