Otitis Externa

What is Otitis Externa

Otitis externa is an infection of the outer ear canal. The outer ear canal is the area between the outside of the ear and the eardrum. Otitis externa is sometimes called “swimmer’s ear.”

What are the causes?

This condition may be caused by:

• Swimming in dirty water.
• Moisture in the ear.
• An injury to the inside of the ear.
• An object stuck in the ear.
• A cut or scrape on the outside of the ear.

What increases the risk?

This condition is more likely to develop in swimmers.

What are the symptoms?

The first symptom of this condition is often itching in the ear. Later signs and symptoms include:

• Swelling of the ear.
• Redness in the ear.
• Ear pain. The pain may get worse when you pull on your ear.
• Pus coming from the ear.

How is this diagnosed?

This condition may be diagnosed by examining the ear and testing fluid from the ear for bacteria and funguses.

How is this treated?

This condition may be treated with:

• Antibiotic ear drops. These are often given for 10–14 days.
• Medicine to reduce itching and swelling.

Follow these instructions at home:

• If you were prescribed antibiotic ear drops, apply them as told by your health care provider. Do not stop using the antibiotic even if your condition improves.
• Take over-the-counter and prescription medicines only as told by your health care provider.
• Keep all follow-up visits as told by your health care provider. This is important.

How is this prevented?

• Keep your ear dry. Use the corner of a towel to dry your ear after you swim or bathe.
• Avoid scratching or putting things in your ear. Doing these things can damage the ear canal or remove the protective wax that lines it, which makes it easier for bacteria and funguses to grow.
• Avoid swimming in lakes, polluted water, or pools that may not have the right amount of chlorine.
• Consider making ear drops and putting 3 or 4 drops in each ear after you swim. Ask your health care provider about how you can make ear drops.

Contact a health care provider if:

• You have a fever.
• After 3 days your ear is still red, swollen, painful, or draining pus.
• Your redness, swelling, or pain gets worse.
• You have a severe headache.
• You have redness, swelling, pain, or tenderness in the area behind your ear.

Detailed Information on Otitis Externa

• Acute otitis externa accounts for over 95% of cases of otitis externa and is characterized by development of symptoms within 48 hours of presentation; most often caused by bacterial pathogens (eg, Staphylococcus, Pseudomonas)
• Chronic otitis externa has many causes and is much less frequently bacterial in etiology
• Acute and chronic otitis externa present similarly with otalgia, otorrhea, and abnormal findings on examination of the external ear and auditory canal (eg, erythematous canal, tenderness to manipulation of tragus and pinna)
• Common predisposing factors to the development of otitis externa are excessive moisture in the external auditory canal, obstruction of canal, disrupted epithelial integrity, and disrupted protective cerumen layer in the canal
• Diagnosis of otitis externa is based on clinical presentation; laboratory and imaging studies do not aid in the diagnosis of otitis externa except in very limited clinical situations in which culture can aid in determining exact etiology
• Treatment for most patients with acute otitis externa includes pain management, topical antimicrobials, appropriate aural toilet and removal of external auditory canal debris, ear wick (when indicated), and precipitant avoidance
• Systemic antibiotics are rarely necessary; use of oral antibiotics is limited to patients at high risk of complications (eg, patients with immunocompromise, diabetes, or with history of radiation to the head), patients in whom there is extension of cellulitis outside of the external auditory canal, patients in whom topical medication delivery is not possible (eg, canal stenosis), topical antibiotic treatment failure, and patients with concurrent otitis media
• Monitor patients for symptom resolution; reevaluate patients whose acute symptoms do not improve with treatment in 2 to 3 days and patients without complete symptom resolution in 2 weeks 
• Preventive measures are important to avoid recurrence (eg, drying external auditory canal after exposure to moisture or swimming, avoiding self-inflicted trauma to canal)
• Potential complications of acute otitis externa include malignant otitis externa, extension of infection beyond external auditory canal to surrounding tissues, and canal stenosis
• Prognosis is excellent with adequate treatment and full recovery is expected within 1 week;  patients often experience marked improvement after 1 day 

Pitfalls

• Fever and malaise do not occur in patients with otitis externa limited to the external auditory canal; carefully assess for alternate diagnosis (eg, malignant otitis externa, otitis media with otorrhea) in patients presenting with systemic signs and symptoms 
• Avoid use of oral antibiotic therapy in patients with otitis externa unless otherwise indicated; inappropriate use of oral antibiotics for uncomplicated otitis externa in otherwise healthy individuals leads to persistent infection, recurrence of infection, and antibiotic resistance 
• Avoid topical ototoxic antiseptic and antibiotic regimens in patients with compromised tympanic membrane integrity (eg, perforation, tympanostomy tubes); confirm integrity of intact tympanic membrane with history and direct visualization before treating external otitis with topical ototoxic medications 

• Otitis externa is inflammation of the external auditory canal with or without infection 

Classification

• Classification based on chronicity
  • Acute otitis externa (also known as swimmers’ ear or tropical ear) 
    • Characterized by marked inflammation of the external auditory canal occurring within 48 hours of presentation 
    • Almost always is cellulitis of the external auditory canal skin and subdermis; infection may involve the pinna, tragus, and/or tympanic membrane 
    • Over 95% of cases of otitis externa are acute 
  • Chronic otitis externa
    • Various definitions exist, including:
      • A single episode of otitis externa lasting longer than 4 weeks, or 
      • 4 or more episodes of otitis externa in 1 year, or 
      • Inflammation lasting 3 months or longer 
    • Causes are numerous; noninfectious causes are more common 
• Classification based on extent of inflammation
  • Diffuse otitis externa
    • Characterized by extensive, diffuse inflammation of the external ear canal
  • Localized otitis externa 
    • Characterized by localized, focal inflammation of the external ear canal (eg, furuncle)
• Classification based on severity 
  • Mild
    • Characterized by mild signs and symptoms
  • Moderate
    • Canal lumen is partially occluded
    • Characterized by increasing pruritus and pain
  • Severe
    • Canal lumen is obstructed
    • Associated with intense pain and extra-canal signs (eg, auricular cellulitis, regional lymphadenopathy)

History

• Acute otitis externa
  • Rapid onset of symptoms within 48 hours 
  • Acute otitis externa (eg, bacterial infection) can complicate chronic otitis externa 
  • Up to 90% of cases are unilateral 
• Chronic otitis externa
  • Recurrent or persistent symptoms lasting 1 month to more than 3 months 
  • Often characterized by a waxing and waning course with intermittent disease exacerbations over the course of years 
  • Up to 50% of cases are bilateral 
• Symptoms of ear canal inflammation
  • Discomfort in the external auditory canal is the most characteristic symptom and is present in most patients 
  • Otalgia
    • Pain is often intense and may worsen with jaw motion 
    • Characteristically described as disproportionate to examination findings 
    • Occurs in up to 70% of patients with acute otitis externa 
  • Pruritus
    • Often a precursor to otalgia
    • Occurs in up to 60% of patients with acute otitis externa 
    • Often more pronounced in patients whose cause of disease is otomycosis, allergy, or chronic and dermatologic in nature
  • Sensation of fullness
    • Occurs in up to 22% of patients with acute otitis externa 
  • Decreased auditory acuity
    • May be secondary to external auditory canal obstruction (eg, swelling, debris) 
  • Referred jaw pain may occur 

Physical examination

• Tenderness of the tragus when pushed and the pinna when gentle traction is applied are hallmark signs of ear canal inflammation 
  • Exquisite pain elicited with manipulation of the tragus or pinna is characteristic, especially in patients with acute otitis externa
• Other evidence of ear canal inflammation on direct visualization:
  • Diffuse external auditory canal edema and erythema occur in the majority of patients
  • Occasionally, inflammatory changes extend to the pinna and adjacent skin 
  • Other variable signs
    • Otorrhea 
      • Usually scant early in illness
      • Often evolves to thick and clumpy or purulent discharge mixed with soft white cerumen later in illness
    • Regional periauricular lymphadenopathy and edema can develop late in patients with severe disease 
    • Tympanic membrane erythema with normal mobility can develop if inflammation extends to the external tympanic membrane, causing myringitis
    • Isolated pustular lesion in the external auditory canal can be observed in patients with localized otitis externa 
• In severe disease, external auditory canal can become nearly obstructed by edema, otorrhea, and additional debris 
• Other external auditory canal findings in patients with chronic otitis externa vary depending on cause 
  • Patients with contact dermatitis (irritant or allergic) may have a maculopapular rash and excoriations
    • When allergic in nature, characteristic rash assumes a patterned distribution with concentration in the conchal bowl and possible linear erythematous streaks (representing drip marks) extending from ear canal
  • Patients with chronic dermatologic conditions show eczematous changes with lichenification and epithelial hyperkeratosis
  • Patients with seborrhea show a lack of cerumen, with dry and flaky or greasy, yellowish skin in canal 
• Characteristics of fungal infections 
  • Fluffy, cottonlike white debris with sprouting hyphae in canal is typical for Candida species
  • Moist white plug dotted with black debris (wet newspaper appearance) is typical for Aspergillus niger infection
  • Thick otorrhea of various colors (eg, black, gray, bluish green, yellow, white)
  • Infection often localizes initially in the medial aspect of the canal in the inferior recess (immediately adjacent to the lower aspect of the tympanic membrane)

Causes

• Acute otitis externa
  • Disruption of external auditory canal epithelium (eg, from trauma to canal or breakdown of epithelium) or natural host defenses (eg, disruption of protective cerumen layer, obstruction of canal drainage, disruption of the normal acidic environment) predisposes to infection 
  • Elements that predispose patients to infection are often multifactorial 
  • 98% of pathogens responsible for disease in North America are bacterial; infection is often polymicrobial 
    • Pseudomonas aeruginosa (20%-60% of cases) 
    • Staphylococcus aureus (10%-70% of cases), including MRSA 
    • Other non-Pseudomonas gram-negative organisms (2%-3% of cases) 
  • Fungal pathogens are responsible for less than 2% of acute otitis externa cases; however, topical antibiotics used to treat acute otitis externa can lead to secondary fungal infection 
    • Aspergillus and Candida are the most commonly encountered fungal pathogens
• Chronic otitis externa has many causes, including: 
  • Complication of inadequately treated bacterial acute otitis externa or fungal infection (eg, otomycosis)
  • Complication of recalcitrant bacterial infection in immunocompromised patients
  • Recurrence or persistence of bacterial infection secondary to lack of preventive measures (eg, avoidance of moisture or trauma)
  • Underlying condition, such as:
    • Allergic contact dermatitis involving the external auditory canal 
      • Causes include drugs (eg, neomycin, other otic preparations), chemicals (eg, detergents, soaps, shampoos, cosmetics, hair spray or hair products), metals (eg, nickel, silver), leather, rubber, and plastics (eg, hearing aid molds)
    • Irritant contact dermatitis (typically caused by products such as shampoos, detergents, and hair products)
    • Dermatoses involving the external auditory canal (eg, atopic dermatitis/eczema, seborrheic dermatitis, contact dermatitis)
    • Autoimmune disease (eg, Wegener granulomatosis, sarcoidosis) 
    • Malignancy

Risk factors and/or associations

Age

• Peak incidence in children aged 7 to 12 years and adults aged 65 to 74 years 
• Rare in children younger than 2 years 

Genetics

• Patients with type A blood group are more susceptible to otitis externa 

Other risk factors/associations

• Seasonality
  • More frequent in summer months in North America 
  • More frequent in warm, humid climates 
• Geographic influences
  • In the United States, disease is most common in the south and least common in the west 
• Predisposing factors that increase risk of acute otitis externa include:
  • Excessive moisture in the external auditory canal (eg, frequent swimming, prolonged exposure to water or sweat) 
    • Acute otitis externa is 5 times more common in regular swimmers 
  • Obstruction of external auditory canal 
    • Causes include foreign body, cerumen impaction, hearing aids, earplugs, ear phones, canal stenosis, dermoid cyst, or sebaceous cyst
    • Certain anatomic factors increase risk of obstruction, such as excessively narrow canal, tortuous canal, excessive hair in canal, and abnormal cerumen production
  • Disrupted epithelial barrier or loss of protective cerumen layer in the canal 
    • Self-induced trauma (eg, instrumentation, cleaning with cotton-tipped swabs)
    • Dermatologic conditions (eg, eczema, seborrhea, psoriasis)
    • Purulent drainage from acute otitis media through tympanostomy tubes or perforated tympanic membrane can macerate epithelium
    • Contact irritation from products (eg, soaps, detergents), allergic irritation, or foreign objects (eg, hearing aids, ear plugs)
    • Excessive cleaning 
    • Chronic otitis externa predisposes individuals to acute otitis externa 
    • Prior radiation therapy to head and neck
• Otomycosis is more common in tropical countries, after person has taken long-term topical antibiotic therapy; also more common in people with diabetes and those who are immunocompromised 
• More severe and persistent acute otitis externa occurs in patients with immunocompromise (eg, HIV, diabetes) 

Diagnostic Procedures

Primary diagnostic tools

• Diagnosis of acute otitis externa is based on clinical presentation; laboratory and imaging studies do not aid in the diagnosis of acute otitis externa 
  • Rapid onset (within 48 hours occurring in the past 3 weeks) and signs and symptoms of ear canal inflammation are diagnostic of acute otitis externa 
• Select patients presenting with otitis externa may require bacterial and/or fungal cultures of otorrhea to specify cause
  • Indications for bacterial and fungal cultures of external auditory canal discharge include patients with:
    • Resistant or recurrent otitis externa with immunocompromise or a history of frequent topical antibiotic use 
    • Chronic otitis externa 
    • Suspected significant complications (eg, necrotizing otitis externa) 

Laboratory

• Bacterial culture of external auditory canal discharge
  • Obtain swab of medial aspect of canal for culture and sensitivity 
  • Interpret cultures from the external ear with caution; external auditory canal cultures are often contaminated with normal skin flora or grow colonizing organisms rather than true pathogens 

Differential Diagnosis

• Referred pain – Common cause of otalgia
• Necrotizing otitis externa (malignant otitis externa)
• Acute Otitis media 
• Chronic suppurative otitis media
• Dermatoses involving the external auditory canal
• Allergic or contact dermatitis involving the external auditory canal
• Foreign body in the external auditory canal
• Cholesteatoma
• Herpes zoster oticus (Ramsay Hunt syndrome)
• Malignancy – Rarely, squamous cell carcinoma presents similarly to otitis externa with ear discomfort and otorrhea. A mass in the external auditory canal evident on examination distinguishes malignancy from otitis externa. Definitive diagnosis is confirmed by biopsy of lesion

Treatment Goals

• Control symptoms 
• Eradicate infection 
• Promote antibiotic stewardship
• Avoid precipitating factors

Admission criteria

• Not indicated for patients with uncomplicated otitis externa
• May be required for patients worsening on maximum outpatient therapy, certain patients with severe immunocompromise, and patients with severe complications (eg, malignant otitis externa) 

Recommendations for specialist referral

• Patients with persistent foreign body despite attempts at removal or debris obstructing canals despite attempts at relieving obstruction require further evaluation and management by an otolaryngologist 
• If condition does not respond or worsens on standard therapy, refer patient to an otolaryngologist for further diagnostic and treatment recommendations; consider managing patients requiring oral antibiotics for otitis externa in consultation with subspecialist 
• Refer patients with suspected malignant otitis externa or persistent chronic otitis externa despite management to an otolaryngologist for further diagnostic and treatment recommendations 

Treatment Options

Pain management is paramount for patients with acute otitis externa 

• Most patients will experience diminished pain with prompt administration of topical antibiotic with or without topical corticosteroid
• Oral administration of analgesics is the preferred route of administration 
  • Treat mild to moderate pain with acetaminophen and NSAIDs at fixed intervals 
  • Treat severe pain with opiate narcotics (eg, oxycodone, hydrocodone) sparingly; provide supply for pain control for 2 to 3 days maximum 
    • Maintain caution with use of opiate narcotics owing to risk of masking severe complications (eg, malignant otitis externa) or inadequate treatment
• Patients occasionally require acute analgesia and occasionally procedure-related sedation with opioids (eg, fentanyl citrate, morphine sulfate) 
• Use topical anesthetic preparations with caution; proof of efficacy is lacking and some experts warn that topical preparations may mask the progression of worsening severe disease or the development of complications (eg, malignant otitis externa) 
  • Topical otic anesthetic drops are not FDA approved for treatment of otitis externa 
  • Mandatory reassessment in 48 hours is recommended if topical otic anesthetic drops are prescribed for temporary pain relief
  • Topical otic anesthetic drops are contraindicated in patients with a nonintact tympanic membrane (ie, tympanostomy tubes or perforation)
• Addition of topical steroid preparation combined with topical antibiotic drops may hasten pain relief in patients with acute otitis externa by about 1 day compared with antibiotic drops alone 

Topical antibiotic therapy is first line standard of care treatment for most patients with acute otitis externa 

• Topical antibiotic treatment for 7 days is highly effective; antiseptic/acidifying agents are effective alternatives to topical antibiotic drops for patients with mild acute otitis externa with an intact tympanic membrane 
  • Topical therapy delivers a very high concentration of antimicrobial directly to infected tissue; 100 to 1000 times higher local antibiotic concentrations are achieved with topical compared with systemic antimicrobials 
  • Avoid topical ototoxic antiseptic and antibiotic regimens in patients with compromised tympanic membrane integrity (eg, perforation, tympanostomy tubes), or when tympanic membrane can not be visualized 
• Acetic acid 
  • Most often used for mild disease in clinical practice
  • Preparations lose efficacy if treatment is required beyond 1 week 
  • Symptoms may persist up to 2 days longer in patients treated with acetic acid 
• Preferred topical antibiotic agent is unclear 
  • Base initial choice of topical treatment on patient allergies, risk of ototoxicity, local antibiotic resistance patterns, and ease of dosing 
• Addition of topical steroid to treatment regimen may hasten resolution of canal edema and otorrhea 
• Effective treatment for acute otitis externa is characterized by marked improvement in pain and other symptoms over the course of 2 to 3 days 

Adequate topical medication delivery is important for patients with acute otitis externa 

• Perform aural toilet and/or place ear wick when indicated to facilitate adequate delivery of topical medication to distal external auditory canal

Avoid topical ototoxic antiseptic and antibiotic preparations in patients with compromised tympanic membrane integrity (ie, perforation or tympanostomy tubes) and when tympanic membrane can not be visualized 

• Topical ototoxic medications that reach the inner ear can lead to hearing loss and vertigo 
• Ototoxic preparations include any containing acidifying agents, aminoglycosides (eg, neomycin, gentamicin, tobramycin), or alcohol and antiseptics 
• Consider children with the following to have a defect in the tympanic membrane:
  • Tympanostomy tube placement within the past year 
  • Those who can taste topical otic medications after placement of the medication in the external auditory canal
  • Those who can expel air from the ear

Systemic antibiotics are rarely necessary 

• Use oral antibiotics with efficacy against Staphylococcus and Pseudomonas when indicated, in consultation with specialist (eg, otolaryngologist, infectious disease specialist) 
  • Consider need for MRSA coverage 
• Indications for systemic antibiotics in select patient populations include: 
  • High risk for complications (eg, those with immunocompromise, diabetes, history of radiation to the head, high risk for development of malignant otitis externa)
  • Evidence of significant extension of cellulitis outside of the external auditory canal or concern for worsening severe disease 
  • Severe disease (eg, canal stenosis or severe canal edema limiting penetration of topical antibiotics) 
  • Persistent bacterial otitis externa failing appropriate topical antibiotic therapy and management 
• Avoid cephalosporins owing to increased risk of recurrence and increased disease persistence; avoid penicillins and macrolides owing to increased disease persistence 
• Oral antibiotic choices for pediatric patients are limited; consider managing patients in consultation with otolaryngologist or infectious disease specialist when oral antibiotics are required
• Treat patients with otitis externa and concurrent draining otitis media with appropriate oral antibiotics aimed at treating the otitis media combined with non-ototoxic topical antibiotics aimed at treating otitis externa 

Patients with otomycosis 

• Manage with surgical debridement plus topical antifungal therapy (eg, clotrimazole 1% cream) in consultation with otolaryngologist
• Gentian violet applied in office is an alternate effective treatment; acidifying agents are additionally beneficial 
• Treat recalcitrant or severe infections with oral itraconazole 
• Topical antibiotic treatment is contraindicated; antibiotics promote further fungal overgrowth 

Patients with chronic otitis externa 

• Recommend aural toilet (if indicated) and preventive precautions for acute otitis externa
• Aim treatment at addressing and controlling underlying cause
  • Avoid contact with irritants in patients with contact dermatitis
  • Topical medium (eg, triamcinolone 0.1% cream) or high-potency steroid agent (eg, desoximetasone 0.05% cream) is usually effective for patients with contact dermatitis or chronic dermatologic condition 
  • Occasionally a short course of oral steroids may be required; topical tacrolimus is effective second line treatment when infection has been excluded 

Drug therapy

• FDA–approved topical otic preparations used to treat acute otitis externa 
  • Acetic acid drops
    • Acetic Acid Otic drops, solution; Adults, Adolescents, and Children >= 3 years: Instill 4—6 drops into the external auditory canal of the affected ear(s). Repeat q2—3hr.
  • Acetic acid/hydrocortisone drops
    • Hydrocortisone, Acetic Acid Otic drops, solution; Adults, Geriatric, Adolescents, and Children >= 3 years: Insert cotton wick into external ear canal and saturate with solution; keep moist by adding 3—5 drops of solution q4—6h. Replace wick at least once q24h. If preferred, may remove wick after 24 h; however, continue dosage of 3—5 drops into the ear(s) 3—4x/day for as long as indicated. Use lower end of dosage for children.
  • Ciprofloxacin drops 
    • Ciprofloxacin Hydrochloride Otic drops, solution; Children and Adolescents: 0.5 mg (0.25 mL) in affected ear(s) every 12 hours for 7 days.
  • Ciprofloxacin/hydrocortisone drops
    • Ciprofloxacin Hydrochloride, Hydrocortisone Otic drops, suspension; Adults, Adolescents, and Children 1 year and older: 3 drops instilled into the affected ear(s) twice daily for 7 days.
  • Ciprofloxacin/dexamethasone otic suspension
    • Ciprofloxacin Hydrochloride, Dexamethasone Otic drops, suspension; Adults, Adolescents, Children and Infants >= 6 months: 4 drops into affected ear(s) bid x 7 days.
  • Neomycin/polymyxin B/hydrocortisone drops
    • Neomycin, Polymyxin B, Hydrocortisone Otic drops, solution; Infants, Children, and Adolescents: 3 drops in affected ear(s) 3—4 times per day. Treatment should not be continued longer than 10 days.
    • Neomycin, Polymyxin B, Hydrocortisone Otic drops, solution; Adults: 4 drops in affected ear(s) 3—4 times per day. Treatment should not be continued longer than 10 days.
  • Ofloxacin drops 
    • Ofloxacin Otic drops, solution; Infants and Children age 6 months up to 13 years: 5 drops (0.25 mL or 0.75 mg) instilled into the affected ear(s) once daily for 7 days.
    • Ofloxacin Otic drops, solution; Adults and Adolescents: 10 drops (0.5 mL or 1.5 mg) instilled into the affected ear(s) once daily for 7 days.
• Topical antifungal agent for patients with otomycosis
  • Clotrimazole otic solution 
    • Clotrimazole Topical solution; Children and Adolescents 2 to 17 years: Apply to affected skin and surrounding areas twice daily.
    • Clotrimazole Topical solution; Adults: Apply to affected skin and surrounding areas twice daily.
• Topical steroid preparations for patients with chronic otitis externa and contact dermatitis or chronic dermatologic conditions 
  • Triamcinolone Acetonide Topical 0.1% cream; Adults: apply a small amount to external aural canal meatus twice daily.
  • Desoximetasone Topical 0.05% cream; Adults, Adolescents, and Children >= 10 years: Apply a small amount to external aural canal meatus twice daily.
• Oral antibiotics
  • Rarely needed except for select patient populations, including: 
    • Immunocompromised people
    • Patients with diabetes
    • Patients with evidence of cellulitis extension outside of the external auditory canal)
  • Ciprofloxacin
    • Ciprofloxacin Hydrochloride Oral tablet; Adults: 500 to 750 mg PO every 12 hours for 7 to 14 days.
  • Treat otitis externa requiring oral antibiotics in consultation with a subspecialist (eg, otolaryngologist, infectious disease consultant)

Nondrug and supportive care

Ensure appropriate and adequate topical medication delivery 

• Before patient discharge, ensure patency of external auditory canal for adequate penetration of topical medications by performing aural toilet (ie, ear lavage) and/or placement of ear wick when indicated
  • Aural toilet 
    • Clear debris with body-temperature fluid irrigation (eg, water, saline, hydrogen peroxide), gentle suctioning, and/or dry mopping with cotton-tipped applicator
      • Avoid irrigation in the following
        • Patients with nonintact tympanic membrane
        • Patients with poorly controlled diabetes or immunocompromise, owing to association of malignant otitis externa following irrigation in these patient populations
    • Remove impacted cerumen and any foreign bodies
  • Ear wick 
    • Place an expandable cellulose (preferred) or ribbon gauze wick gently in the ear canal to ensure distal penetration of antimicrobial agent; once placed, moisten with 6 drops of antibiotic preparation 
    • Indicated for patients with significant edema of the external auditory canal (ie, when the majority of tympanic membrane cannot be visualized) and when external auditory canal obstruction is anticipated to limit delivery of antimicrobial agent to the distal canal 
    • Ear wick will usually expel itself in the first few days as inflammation improves; alternatively, patient can remove wick after symptoms improve in or clinician can remove at follow-up 
• Demonstrate effective installation of first dose of ear drops in office when possible before patient discharge 
  • A common cause of initial treatment failure is improper installation of topical antibiotic drops; up to 40% of patients self-administer drops incorrectly 
  • Instruct patients on effective installation of topical medication drops with the following sequence:
    • Patient lies down with affected ear upward
    • Optimally, someone other than the patient administers drops until the affected external auditory canal is filled
    • Gently vibrate or manipulate pinna and outer ear to ensure complete filling and eliminate air trapping
    • Leave medication in place for at least 3 to 5 minutes

Recommend precipitant avoidance 

• Reduce moisture exposure to the ear
  • Avoid water sports and swimming with head submersion under water; competitive swimmers should avoid swimming for at least 2 to 3 days 
  • Use earplugs or cotton with petroleum jelly when bathing
• Use a hair dryer on the lowest setting to reduce any remaining moisture in the external auditory canal after potential water exposure
• Avoid hearing aids, ear phones, and ear plugs (when not protecting from water exposure while bathing) until pain and discharge have subsided 

Recommend preventive measures to avoid precipitating factors and prevent recurrent or recalcitrant infection 

• Dry external auditory canal thoroughly after exposure to moisture or swimming
• Avoid self-induced trauma (eg, cleaning ears with foreign objects)

Procedures

Surgical debridement of ear canal 

General explanation

• Surgical removal of debris from the ear canal; usually performed under direct visualization by otolaryngologist using the open otoscope head, low suction, and instruments dependent on indication
• Anesthesia may be required depending on extent of debridement required and level of patient cooperation

Indication

• Mainstay of treatment for otomycosis and necrotizing otitis externa
• Use to treat external canal stenosis that does not resolve with aural toilet
• Use to treat localized otitis externa requiring extensive incision and drainage of furuncle or abscess

Contraindications

• No absolute contraindications

Complications

• Iatrogenic trauma to external auditory canal

Interpretation of results

• Culture of any retrieved purulent material is processed for microbial growth and sensitivities

Comorbidities

• Patients with underlying immunodeficiency (eg, HIV, diabetes)
  • Treat with oral antibiotics in addition to topical otic preparation owing to higher risk of local spread of infection and malignant otitis externa 
  • Aggressive debridement is a critical measure
  • Consider and monitor closely for development of otitis externa; imaging with CT or MRI may be necessary to confirm diagnosis 
  • Consider Aspergillus species as a potential cause 
• Patients with a nonintact tympanic membrane
  • Treat with non-ototoxic topical preparations 

Monitoring

• Monitor for resolution of symptoms
  • Persistent severe pain and worsening symptoms that do not improve with 2 to 3 days of appropriate therapy for acute otitis externa require urgent reevaluation 
    • Reevaluate for patency of external auditory canal; aural toilet and placement of ear wick may be required
    • Reevaluate for the presence of a foreign body 
    • Reevaluate patient understanding of administration of ear drop technique and medication compliance; reevaluate patient compliance with avoidance of modifiable exacerbating factors (eg, swimming, self-induced trauma to the canal) and prescribed use of ear drops
    • Reevaluate for the development of complications (eg, malignant otitis externa, contact allergy to medication) and alternate diagnosis
    • Consider ear culture for bacterial and fungal pathogens; addition of a systemic antibiotic covering Pseudomonas and Staphylococcus species may be required
    • Consider referral to otolaryngologist for further diagnostic and treatment recommendations (eg, surgical debridement)
  • Consider persistence of symptoms beyond 2 weeks a treatment failure requiring reevaluation 
    • Reevaluate for alternate diagnosis (eg, malignancy, contact dermatitis, dermatosis of the external auditory canal)
    • Consider fungal cause (ie, otomycosis)

Complications

• Malignant otitis externa 
  • Often considered a rare complication of acute otitis externa
• Extension of infection from ear canal to surrounding structures (eg, facial cellulitis, auricular cellulitis, mastoiditis, perichondritis, chondritis) 
  • Can complicate acute otitis externa
• Stenosis of the external auditory canal 
  • Can complicate acute severe disease or can result from ongoing chronic infection
• Hearing loss 
  • Can result from ongoing chronic infection or ototoxicity of ear drops with chronic exposure to inner ear; can also be secondary to canal obstruction
• Chronic otitis externa
  • Can complicate acute otitis externa
• Otomycosis
  • Can result from prolonged use of topical antibiotics 
  • More common in patients with immunocompromise or diabetes
• Fibrosis of the medial external auditory canal
  • Can complicate chronic otitis externa

Prognosis

• Full recovery with adequate treatment is expected for most patients
• Expect rapid symptom improvement given adequate and appropriate treatment for acute otitis externa
  • Patients often improve after 1 day of treatment 
  • Most patients experience minimal or no pain after 4 days of treatment

Prevention

• Advise patients to avoid excessive moisture and trauma to the auditory canal 
  • Acidification with a topical solution of 2% acetic acid is an effective drying technique after exposure to moisture 
    • Application of topical isopropyl alcohol is suggested as an alternate regimen 
  • Counsel swimmers on importance of evacuating water from external auditory canal after swimming (eg, head tilt and gentle ear traction to promote water evacuation) 
  • Patient should dry wet ears with a hair dryer on low setting after exposure to moisture 
  • Wear soft, malleable ear plugs while swimming 
  • Patient should avoid manipulation or instrumentation of the external auditory canal to prevent self-induced trauma; stop frequent ear cleaning, especially with cotton-tipped applicators 
  • Ensure that hearing aids are well fitting and removed nightly; avoid hard earplugs owing to risk of trauma 
  • Ensure that underlying dermatologic conditions are adequately treated 

Sources

Rosenfeld RM et al: Clinical practice guideline: acute otitis externa. Otolaryngol Head Neck Surg. 150(1 Suppl):S1-S24, 2014 Reference