Acute otitis externa in children and adolescents

INTRODUCTION — 

Otitis externa, also known as external otitis or swimmer's ear, is defined as diffuse inflammation of the external auditory canal (EAC), which may also involve the pinna or tympanic membrane.

This topic will review the anatomy, epidemiology, clinical features, and treatment of acute otitis externa in children and adolescents. Related topics include:

●Acute otitis media in children (see "Acute otitis media in children: Epidemiology, microbiology, and complications" and "Acute otitis media in children: Clinical manifestations and diagnosis" and "Acute otitis media in children: Treatment")

●Otitis externa in adults (see "Acute otitis externa in adults: Pathogenesis, clinical features, and diagnosis" and "Acute otitis externa in adults: Treatment")

●Necrotizing (malignant) otitis externa (see "Necrotizing (malignant) external otitis")

TERMINOLOGY — 

The following terms are used to describe ear infections in children:

●Otitis externa – Otitis externa (OE; also called external otitis) refers to diffuse inflammation of the external auditory canal (EAC), which may also involve the pinna or tympanic membrane.

OE can be acute or chronic:

•Acute otitis externa (AOE) – The vast majority of cases of pediatric OE are acute infections, which have onset over one to two days and resolve within a week or so after administering appropriate topical therapy. AOE, also known as acute external otitis or swimmer's ear, is the focus of this topic.

•Chronic OE – Chronic OE is a distinct condition characterized by chronic inflammation of the external ear. It is often caused by fungal pathogens (eg, Candida), though occasionally bacterial pathogens are responsible, particularly those that are difficult to eradicate (eg, methicillin-resistant Staphylococcus aureus [MRSA]). Inflammatory dermatoses are another uncommon cause of chronic inflammation in the external ear (see 'Differential diagnosis' below). Chronic otitis externa is beyond the scope of this topic.

●Otitis media – Otitis media refers to infection of the middle ear fluid and inflammation of the mucosal lining of the middle ear space.

Like OE, otitis media can be acute or chronic. These conditions are discussed in detail separately:

•Acute otitis media (AOM; also called suppurative otitis media) (see "Acute otitis media in children: Epidemiology, microbiology, and complications" and "Acute otitis media in children: Clinical manifestations and diagnosis" and "Acute otitis media in children: Treatment")

•Chronic suppurative otitis media (CSOM) (see "Chronic suppurative otitis media (CSOM): Clinical features and diagnosis" and "Chronic suppurative otitis media (CSOM): Treatment, complications, and prevention")

ANATOMY AND PHYSIOLOGY

Anatomy of the ear canal — The external auditory canal (EAC) is a cylinder extending from the conchal cartilage of the pinna to the tympanic membrane (figure 1). The lateral (outer) portion of the EAC is cartilaginous, and the medial (inner) portion is bony. The skin of the cartilaginous portion contains cerumen glands, sebaceous glands, and hair follicles. The skin of the inner bony portion of the canal is thin without subcutaneous tissue, and the dermis lies directly on the periosteum.

The lining of the ear canal is keratinizing squamous epithelium that undergoes continual sloughing.

The ear canal is bound superiorly by the middle cranial fossa, anteriorly by the temporomandibular joint (TMJ), medially by the tympanic membrane, posteriorly by the mastoid cavity, and inferiorly by the soft tissues of the neck. Infections in the EAC can spread to these adjacent tissues.

The fissures of Santorini are a series of embryologic cracks in the anterior aspect of the cartilaginous portion of the EAC through which nerves and blood vessels pass. These fissures also allow potential spread of an EAC infection to the parotid region, TMJ, and the upper neck.

Protective mechanisms — There are several defensive mechanisms in the ear that help prevent EAC infections:

●The tragus and conchal cartilage partially cover the opening of the ear canal and limit the amount of water or other substances that can enter the canal.

●Hair follicles in the lateral (outer) portion of the EAC prevent contaminants from entering the canal.

●Cerumen is hydrophobic and causes a slightly acidic pH which inhibits bacterial or fungal growth. The sticky quality of cerumen also helps trap fine debris.

●Ear canals are typically self-cleaning. Epithelial migration from the medial (inner) to lateral (outer) ear canal is a natural process that allows the canal to remove keratin debris and cerumen. It begins at the center of the TM and transverses the ear canal from medial to lateral. Interference with these defensive mechanisms contributes to the development of acute otitis externa.

EPIDEMIOLOGY

Incidence — Acute otitis externa (AOE) occurs more commonly in children than adults, with a peak incidence at age 5 to 14 years [1,2]. However, AOE occurs in all age groups, and approximately 10 percent of people develop AOE at some point during their lifetime [2]. In the United States, it is estimated that there are more than two million health care visits for AOE annually [2].

Ambulatory visits for AOE peak in the summer months and are highest in regions with warm humid climates and/or frequent exposure to water and swimming (eg, the southern states in the United States) [3].

Risk factors — Risk factors for AOE include water exposure, aggressive EAC cleaning, and other factors that interfere with the natural protective mechanisms of the ear canal (see 'Protective mechanisms' above):

●Swimming or other water exposure is one of the most common risk factors, which is why AOE is often called "swimmer's ear." Moisture in the EAC leads to breakdown of the skin-cerumen barrier, changing the microflora to predominantly gram-negative bacteria.

●Soapy deposits left in the ear canal can also contribute to bacterial growth.

●EAC trauma due to excessive cleaning or scratching of the ear canal is another important risk factor. Excessive removal of cerumen reduces this important protective barrier. In addition, abrasions of the EAC from swabs or other implements allows bacteria to gain access to the canal skin. At-home removal of cerumen with cotton swabs or other methods should be discouraged [4]. Manual removal of impacted cerumen in an otolaryngology office has not been found to increase the incidence of AOE in the two weeks following the procedure [5].

●Devices that occlude the EAC such as hearing aids or ear buds can interfere with the natural epithelial migration process and lead to a buildup of debris in the canal.

●Atopic dermatitis or allergic contact dermatitis (from earrings, or chemicals in shampoos) can lead to increased debris in the EAC.

●Alkaline ear drops reduce the acidity in the ear canal, which decreases the protective effect of cerumen.

MICROBIOLOGY — 

Most cases of AOE are caused by bacteria. The most commonly isolated pathogens are Pseudomonas aeruginosa (20 to 60 percent of cases), Staphylococcus aureus (10 to 70 percent of cases), and other gram-negative organisms [6]. Polymicrobial infections are common. Fungal pathogens are not common causes of AOE, but they can play a role in chronic external ear infections, particularly after prolonged or recurrent use of topical antibiotics.

CLINICAL FEATURES

Presentation — Patients with acute otitis externa (AOE) usually present with otalgia, pruritus, or a feeling of fullness in the ear. The onset of symptoms is usually rapid, typically within 48 hours. If the ear canal is markedly swollen, the patient may report poor hearing in the affected ear. Fever is uncommon.

When taking the history, the clinician should ask about predisposing factors (eg, swimming) and whether the child has history of a nonintact tympanic membrane (eg, prior tympanostomy tube placement or tympanic membrane perforation) or immunodeficiency. (See 'Risk factors' above.)

On physical examination, most patients have tenderness of the tragus (when pushed) and/or pinna (when pulled). Patients with moderate to severe AOE often experience extreme pain when the otoscope is placed in the ear canal. In most children with severe AOE, the diagnosis can be made with external examination alone, and otoscopic examination is not necessary.

The ear canal typically appears swollen, erythematous, and macerated with discharge present (picture 1A-C). The tympanic membrane (TM), if visualized, may show mild erythema but should otherwise appear normal without middle ear effusion. However, the TM often cannot be seen due to EAC swelling. Near complete obliteration of the EAC lumen is more likely in young children due to the smaller diameter of the EAC.

Severity — The spectrum of AOE ranges from mild to severe, based upon the presenting symptoms and physical examination (figure 2):

●Mild AOE – Mild AOE is characterized by mild discomfort and pruritus. Canal erythema and discharge are present but there is little edema (picture 1A).

●Moderate AOE – Moderate AOE is characterized by moderate pain and pruritus. Pain can be elicited by manipulating the pinna or inserting an otoscope. The EAC is erythematous and edematous and the TM can be only partially seen (picture 1B).

●Severe AOE – Severe AOE is characterized by severe pain both at rest and with manipulation of the pinna. The EAC is extremely swollen such that little to no lumen is visible (picture 1C). Peri-auricular erythema or lymphadenopathy may be present. Insertion of the otoscope is extremely painful and, in most children, the diagnosis can be made without otoscopic examination. The TM cannot be seen on routine examination. In rare cases, severe AOE can be complicated by surrounding periauricular and facial cellulitis (picture 2).

●Necrotizing (malignant) otitis externa – Malignant otitis externa, also called necrotizing external otitis, is a rare, severe form of otitis externa that is almost always caused by P. aeruginosa. It most commonly occurs in adults, but it has been described in children, particularly children with underlying immunodeficiency [7,8]. In a review of 786 cases of malignant otitis externa, only 13 (2 percent) occurred in patients <18 years old [8]. The infection spreads from the skin of the EAC to the bone and soft tissues surrounding the ear. Patients may have severe otalgia and otorrhea with pain that appears out of proportion to examination findings. Granulation tissue, edema, erythema, and necrosis of ear canal skin may be seen on examination. Cranial nerve paralysis can occur, and facial nerve paralysis is more common in children compared with adults [9]. Magnetic resonance imaging (MRI) and computed tomography (CT) can demonstrate extension of the infection into the surrounding bony structures [10,11]. Malignant otitis externa is discussed in greater detail separately. (See "Necrotizing (malignant) external otitis".)

DIAGNOSIS

Clinical diagnosis — Acute otitis externa (AOE) is diagnosed clinically based upon the characteristic clinical presentation (rapid onset of otalgia, pruritus, and/or a feeling of fullness in the ear) in conjunction with signs of ear canal inflammation on examination (eg, tenderness of the tragus and/or pinna, diffuse ear canal edema and erythema with or without otorrhea, regional lymphadenitis, tympanic membrane erythema, or cellulitis of the pinna and adjacent skin) (table 1) [12].

Limited role for cultures — Cultures (obtained by swabbing the ear canal) are not typically necessary except in the following circumstances:

●The infection is spreading to the surrounding tissues (eg, cellulitis of the pinna or parotid region)

●Patients with immunodeficiency (eg, primary immunodeficiency, receiving immunosuppressive therapy after transplant, receiving chemotherapy)

●Patients with recurrent or chronic otitis externa

●Patients who do not respond to initial therapy

DIFFERENTIAL DIAGNOSIS — 

The differential diagnosis of acute otitis externa includes other conditions that cause ear pain and erythema.

●Other causes of ear pain – Mild acute otitis externa (AOE) can mimic the appearance of acute otitis media (AOM) because the tympanic membrane (TM) can appear erythematous in both conditions. The presence of significant EAC swelling and erythema differentiates AOE from AOM. In addition, when feasible, performing pneumatic otoscopy can help differentiate between the two conditions. In AOE, TM mobility is normal (no middle ear effusion), whereas TM mobility is impaired in AOM. (See "Acute otitis media in children: Clinical manifestations and diagnosis", section on 'Tympanometry and acoustic reflectometry'.)

Distinguishing between AOE and AOM in a child with a nonintact TM (eg, prior tympanostomy tube placement or TM perforation) can also be challenging since both conditions present with otorrhea and ear discomfort/pruritus; however, AOE generally causes more severe pain and swelling in the ear canal. Differentiating between these two conditions is less critical since both can be treated with topical antibiotic drops. (See 'Antimicrobial therapy' below and "Tympanostomy tube otorrhea in children: Causes, prevention, and management", section on 'Treatment'.)

The evaluation of ear pain in children is discussed in detail separately. (See "Evaluation of earache in children".)

●Other causes of outer ear inflammation – Inflammatory dermatoses involving the ear canal can mimic AOE. Examples include eczema (atopic dermatitis), seborrhea (seborrheic dermatitis), and psoriasis (psoriasiform dermatitis). Patients with these conditions tend to have chronic ear inflammation, and these diagnoses are more likely to be confused with chronic otitis externa [13]. (See "Overview of dermatitis (eczematous dermatoses)".)

Contact dermatitis of the ear canal can occur due to an allergic reaction to ototopical drops (eg neomycin) (picture 3) or contact with other materials adjacent to the ear canal (eg nickel in an earring) [14]. (See "Allergic contact dermatitis in children".)

Otomycosis is a fungal infection of the EAC most commonly caused by Candida and Aspergillus species [15]. It is more commonly seen in tropical or subtropical regions. It can also occur after repeated or prolonged use of ototopical antibiotic drops. Otomycosis typically presents as severe itching and crusting of the outer ear. (See "Acute otitis externa in adults: Treatment", section on 'Otomycosis'.)

Rarely, malignant conditions (eg acute myeloid leukemia, myeloid sarcoma) can present with acute external ear inflammation [16,17]. There are case reports of Langerhans cell histiocytosis presenting similar to AOE [18,19].

The approach to evaluating otorrhea in children is discussed separately. (See "Otorrhea (ear discharge) in children: Causes and evaluation".)

MANAGEMENT — 

Management of acute otitis externa (AOE) consists of analgesic therapy, water precautions, aural toilet (if necessary), and ototopical antibiotic drops. Most children with AOE can be managed in the outpatient setting, though occasionally a child with severe AOE may require hospital admission (eg, if more severe cellulitis extending beyond the ear canal develops) [20].

Pain relief — Pain relief is an important part of managing AOE. Mild to moderate pain usually responds to acetaminophen and/or nonsteroidal anti-inflammatory drugs (NSAIDs; eg, ibuprofen). For patients with AOE who present to the emergency department with severe acute pain, an opioid medication (eg hydrocodone or oxycodone) combined with acetaminophen or ibuprofen is sometimes necessary. (See "Pain in children: Approach to pain assessment and overview of management principles", section on 'Pharmacologic therapy'.)

Topical (otic) analgesics should be avoided in patients with AOE.

Water and other precautions

●Avoid swimming – Patients should be advised to avoid swimming and other water sports for 7 to 10 days while the AOE infection is being treated. In mild cases, it is reasonable to allow the child to enter a pool or other water facility if the child can reliably comply with instructions to avoid submersion. Competitive swimmers can return to swimming two to three days after completing treatment or, if using well-fitting earplugs with or without a swim headband, they can swim once the pain resolves.

●Bathing and showering – Patients can take baths or showers, but they should be advised to keep the ear dry and avoid submersion.

●Avoid inserting devices into the ear – Ear buds, hearing aids, and similar devices should be avoided until after symptoms have resolved [12,21]. In addition, these devices should be disinfected prior to reuse.

Aural toilet (optional) — Aural toilet refers to thoroughly cleaning the ear canal to remove gross amounts of debris. This is not routinely necessary in most cases of mild to moderate pediatric AOE. However, if there is a large buildup of purulent debris in the canal, carefully removing some of the debris permits better examination of the ear and it may facilitate delivery of ototopical medications.

Cleaning of the ear canal can be achieved using a cotton pledget wrapped tightly around a curette or a wick to soak up excess fluid. Occasionally, a more thorough cleaning may be necessary. This generally involves using a suction catheter or ear curette under direct visualization with either an otoscope or otomicroscope, provided the patient can tolerate the procedure. Instrumentation of the ear canal is often extremely painful and thus this intervention is generally reserved for patients in whom debridement of the canal is deemed necessary (ie, those with severe infections associated with copious debris).

Patients and parents/caregivers should be advised not to insert cotton swabs or other objects into the ear canal themselves in attempt to clear it of debris.

Antimicrobial therapy — Topical antimicrobial therapy is the mainstay of treatment for AOE since it provides a high local concentration of the agent in the ear canal [12,21,22].

Multiple topical antibiotic and antiseptic solutions with and without corticosteroids are available for treatment of AOE (table 2). No studies have definitely shown one topical agent to be superior to another [22,23]. However, results of two clinical trials suggest that treatment with a combined antibiotic plus corticosteroid solution results in faster resolution of symptoms compared with topical antibiotic therapy alone [24,25].

Choice of topical therapy — The choice of topical therapy is based upon the severity of the infection, whether the tympanic membrane (TM) is intact, the cost and availability of different agents, and the preferences of the patient and clinician. Our suggested approach is as follows:

●Mild to moderate AOE with intact TM – For patients with mild to moderate AOE in whom the TM has been visualized and is intact, any of the available topical agents are reasonable (table 2). We typically use fluoroquinolone-containing agents (eg, ciprofloxacin, ofloxacin, ciprofloxacin-hydrocortisone, or ciprofloxacin-dexamethasone) because they provide appropriate antimicrobial coverage and are generally well tolerated. However, other topical antibiotic agents are reasonable alternatives.

An antiseptic agent is another reasonable alternative option for treatment of mild to moderate AOE. Acetic acid is the most commonly used antiseptic agent, but boric acid, aluminum acetate, and N-chlorotaurine have also been studied [23]. Limited clinical trial evidence suggests these therapies have similar efficacy when compared with topical antibiotics (with or without a corticosteroid) [23].

For mild cases of AOE, a time-honored home remedy is a mixture consisting of two parts isopropyl alcohol, one part 5 percent acetic acid (white vinegar), and one part distilled water; a few drops of the mixture are placed in the affected ear three to four times a day. This home remedy has never been formally studied, but the drying effect of the alcohol and the acidifying effect of the vinegar is likely to be effective [12,21].

●Mild to moderate AOE with nonintact TM or unknown TM status – If the TM is not intact (eg, tympanostomy tube in place or TM perforation) or the status of the TM is unknown (eg, if it cannot be visualized due to swelling or tenderness of the ear canal), we suggest a fluoroquinolone-containing treatment (eg, ciprofloxacin, ofloxacin, ciprofloxacin-hydrocortisone, or ciprofloxacin-dexamethasone) because these agents are not ototoxic [12,21]. Agents containing aminoglycosides or alcohol should not be used in this setting due to risk of ototoxicity.

●Severe AOE – For patients with severe AOE (ie, severe pain with extremely swollen ear canal), we suggest a combination fluoroquinolone plus corticosteroid solution (eg, ciprofloxacin-hydrocortisone or ciprofloxacin-dexamethasone). The ear canal is often so swollen in these patients that antibiotic ear drops are unable to pass deep into the canal. In such cases, an expandable small wick (picture 4), typically composed of compressed cellulose, should be placed in the ear canal to allow the drops to enter into the inner canal. After 24 to 48 hours of treatment, the wick will often come out spontaneously as the ear canal edema subsides. Alternatively, it can be removed by the patient or clinician after a few days.

Treatment duration, expected course, and follow-up

●Treatment duration – The usual duration of topical therapy for AOE is seven days. However, if symptoms have not resolved by the end of the seven-day course, treatment should be continued for up to 14 days.

●Expected course – For most children with uncomplicated AOE, symptoms improve within 48 to 72 hours. All symptoms should resolve by the end of the 7- to 14-day treatment course.

●Follow-up – Clinical follow-up is not necessary for children with uncomplicated AOE who improve as expected with topical therapy. Recheck of the ear should be performed if symptoms are not improving or if the patient has a history of recurrent AOE or chronic external ear infections.

Patients with treatment failure (ie, persistent symptoms beyond two weeks or worsening symptoms while on therapy) should be reevaluated, including repeat ear examination, obtaining cultures of ear discharge, and referral to an otolaryngologist. If signs of cellulitis of the pinna or parotid region develop, the patient should immediately seek additional medical care [26].

Limited role for oral antibiotic therapy — Oral antibiotics are rarely indicated for AOE as the available evidence suggests systemic therapy does not offer any additional benefit over topical therapy [12,21,27,28].

Uncommon scenarios wherein systemic antibiotic therapy is appropriate include [12,21]:

●If there is evidence of cellulitis spreading outside the ear canal (picture 2). The unique treatment consideration when treating cellulitis associated with AOE is that empiric antipseudomonal coverage may be warranted in cases of severe cellulitis. Additional details on treatment of cellulitis are provided separately. (See "Skin and soft tissue infections in children >28 days: Evaluation and management", section on 'Systemic antimicrobial therapy'.)

●If the patient has severe AOE in the setting of underlying poorly controlled diabetes mellitus.

●If the patient has underlying immunodeficiency.

PREVENTION OF RECURRENCE — 

Strategies to prevent acute otitis externa (AOE) include:

●Limiting water accumulation in the external auditory canal.

●Maintaining a healthy skin barrier by avoiding excessive cleaning or scratching of the ear canal. (See 'Protective mechanisms' above and 'Risk factors' above.)

●For children who are prone to AOE, using ear plugs and swim head bands while swimming.

●For competitive or frequent swimmers, acidifying ear drops can be used before swimming, after swimming, at bedtime, or all three. A hair dryer can be used on low heat to dry an ear canal after swimming (pull the pinna to open up the ear canal and aim the hairdryer at the canal). In addition, commercially available "ear dryers" can be used to prevent retention of moisture in the EAC.

SOCIETY GUIDELINE LINKS — 

Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Acute otitis media, otitis media with effusion, and external otitis".)

INFORMATION FOR PATIENTS — 

UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5th to 6th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10th to 12th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topics (see "Patient education: Outer ear infection (The Basics)" and "Patient education: How to use ear drops (The Basics)")

●Beyond the Basics topics (see "Patient education: External otitis (including swimmer's ear) (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

●Epidemiology – Acute otitis externa (AOE; also known as external otitis or swimmer's ear) is defined as diffuse inflammation of the external auditory canal (EAC), which may also involve the pinna or tympanic membrane (TM). It is common in children, with a peak incidence at age 5 to 14 years. Approximately 10 percent of people develop AOE during their lifetime. (See 'Epidemiology' above.)

●Risk factors – Risk factors for AOE include (see 'Risk factors' above):

•Swimming or other water exposure

•EAC trauma due to excessive cleaning or scratching of the ear canal

•Devices that occlude the EAC (eg, ear buds or hearing aids)

●Microbiology – The most common pathogens are Pseudomonas aeruginosa, Staphylococcus aureus, and other gram-negative organisms. Polymicrobial infections are common. (See 'Microbiology' above.)

●Clinical presentation – Patients with AOE present with acute onset of otalgia, pruritus, or a feeling of fullness in the ear. If the ear canal is markedly swollen, the patient may report poor hearing in the affected ear. Fever is uncommon. (See 'Presentation' above.)

On examination, most patients have tenderness of the tragus (when pushed) and/or pinna (when pulled). The ear canal appears swollen, erythematous, and macerated with discharge present (picture 1B).

●Severity – The severity assessment, which is based upon presenting symptoms and physical examination (figure 2), informs management decisions. (See 'Severity' above.)

●Diagnosis – AOE is diagnosed clinically based upon the characteristic clinical presentation (acute onset of otalgia, pruritus, and/or a feeling of fullness in the ear) in conjunction with signs of EAC inflammation on examination (table 1). (See 'Clinical diagnosis' above.)

Cultures (obtained by swabbing the EAC) are not typically necessary unless the infection does not respond to initial therapy or is spreading to the surrounding tissues, or if the patient has recurrent or chronic otitis externa or underlying immunodeficiency. (See 'Limited role for cultures' above.)

●Differential diagnosis – The differential diagnosis of AOE includes other causes of acute ear pain (eg, acute otitis media) and other conditions that can cause inflammation of the outer ear (eg, inflammatory dermatoses, contact dermatitis, fungal infection). (See 'Differential diagnosis' above.)

●Management – Management of AOE includes:

•Pain relief – Pain caused by AOE usually responds to acetaminophen and/or nonsteroidal anti-inflammatory drugs (NSAIDs; eg, ibuprofen). Topical (otic) analgesics should be avoided in patients with AOE. (See "Pain in children: Approach to pain assessment and overview of management principles", section on 'Nonopioid analgesics'.)

•Water and other precautions – Patients should be advised to avoid swimming for 7 to 10 days. Baths and showers are permitted, but the ear should be kept dry and submersion should be avoided. Ear buds, hearing aids, and similar devices should be avoided until after symptoms have resolved. (See 'Water and other precautions' above.)

•Aural toilet – Thoroughly cleaning the ear canal to remove gross amounts of debris is not routinely necessary in most cases of mild to moderate pediatric AOE. However, if there is a large buildup of purulent debris in the canal, carefully removing some of the debris permits better examination of the ear and it may facilitate delivery of ototopical medications, provided the patient can tolerate the procedure. Patients and parents/caregivers should be advised not to insert cotton swabs or other objects into the ear canal themselves in attempt to clear it of debris. (See 'Aural toilet (optional)' above.)

•Topical antimicrobial therapy – Topical therapy is the mainstay of treatment for AOE (table 2). The choice of topical therapy is based upon the severity of the infection, whether the TM is intact, the cost and availability of different agents, and the preferences of the patient and clinician. Our suggested approach is as follows (see 'Choice of topical therapy' above):

-Mild to moderate AOE with intact TM – For patients with mild to moderate AOE in whom the TM has been visualized and is intact, any of the available topical agents are reasonable (table 2). We suggest a fluoroquinolone-containing agent with or without a corticosteroid (eg, ciprofloxacin, ofloxacin, ciprofloxacin-hydrocortisone, or ciprofloxacin-dexamethasone) rather than other agents (Grade 2C) because fluoroquinolones provide appropriate antimicrobial coverage and are generally well tolerated. However, other topical antibiotic or antiseptic agents are reasonable alternatives.

-Mild to moderate AOE with nonintact TM or unknown TM status – If the TM is not intact (eg, tympanostomy tube in place or TM perforation) or the status of the TM is unknown (eg, if it cannot be visualized due to swelling or tenderness of the ear canal), we suggest a fluoroquinolone-containing treatment (Grade 2C). Agents containing aminoglycosides or alcohol should not be used in this setting due to risk of ototoxicity.

-Severe AOE – For patients with severe AOE (ie, severe pain with marked swelling of the ear canal), we suggest a combination fluoroquinolone plus corticosteroid (eg, ciprofloxacin-hydrocortisone, or ciprofloxacin-dexamethasone) rather than other agents (Grade 2C). If the ear canal is obstructed due to swelling, an aural wick (picture 4) should be placed to ensure delivery of ear drops to the inner canal.

•Treatment duration – The usual duration of topical therapy for AOE is seven days. However, if symptoms have not resolved by that time, treatment should be continued for up to 14 days. (See 'Treatment duration, expected course, and follow-up' above.)

•Expected course – Symptoms usually improve within 48 to 72 hours after starting therapy. All symptoms should resolve by the end of the 7- to 14-day treatment course. (See 'Treatment duration, expected course, and follow-up' above.)

•Follow-up – Clinical follow-up is not necessary for children with uncomplicated AOE who improve as expected with topical therapy. Recheck of the ear should be performed if symptoms are not improving or if the patient has a history of recurrent AOE or chronic external ear infections. Patients with persistent symptoms beyond two weeks or worsening symptoms while on therapy should be reevaluated, including repeat ear examination, obtaining cultures of ear discharge, and referral to an otolaryngologist. (See 'Treatment duration, expected course, and follow-up' above.)