What is serous otitis with effusion (OME), its pathophysiology, symptoms, and treatment options in both children and adults?

Serous Otitis with Effusion (OME): Definition, Classification, Pathophysiology, Symptoms, and Management

Definition and Classification

Otitis media with effusion (OME) is defined as the presence of fluid in the middle ear space without signs or symptoms of acute infection—specifically, no fever, no acute ear pain, and no bulging red eardrum. 1

• OME is fundamentally distinct from acute otitis media (AOM), lacking acute inflammatory signs such as rapid-onset ear pain, fever, and a bulging eardrum 2
• The condition is characterized by an intact eardrum with fluid behind it that causes conductive hearing loss 2
• Alternative names include ear fluid, serous otitis media, secretory otitis media, and nonsuppurative otitis media 2

Duration-Based Classification

• Acute OME: Duration less than 3 months from diagnosis 1
• Chronic OME: Persisting for 3 months or longer from diagnosis 1, 3

Pathophysiology

OME develops through Eustachian tube dysfunction, which prevents proper middle ear ventilation and drainage. 2

The pathophysiologic sequence involves:

• Viral upper respiratory tract infections always precede the development of OME, causing inflammation of the nasopharyngeal and Eustachian tube epithelium 4
• This viral inflammation leads to Eustachian tube dysfunction, creating negative middle ear pressure 4
• The negative pressure allows secretions containing viruses and bacteria from the nasopharynx to enter the middle ear 4
• OME may occur during or after an upper respiratory infection, spontaneously due to poor Eustachian tube function, or as an inflammatory response following acute otitis media 2
• Bacterial biofilms form on middle ear mucosa and in middle ear effusion, protecting bacteria against antibiotics and immune responses, making the condition more persistent 4

Anatomic and Host Factors

• Eustachian tube dysfunction is particularly common in young children due to anatomic factors 4
• High-risk populations include children with Down syndrome or cleft palate (60-85% prevalence) due to inherent Eustachian tube abnormalities 1, 2
• Craniofacial dysmorphism, respiratory allergy, and gastroesophageal reflux all favor the development of OME 3
• Adenoid hypertrophy can contribute by obstructing the Eustachian tube 4

Symptoms and Clinical Presentation

The hallmark symptom of OME is conductive hearing loss, not ear pain or fever. 2

Primary Manifestations

• Conductive hearing loss is the primary symptom, which can lead to language delays, behavioral issues, and academic difficulties in children 2
• Balance problems may occur 2
• Speech and language development delays 2
• Ear discomfort (not acute pain) 2

Critical Clinical Pitfall

• OME is often asymptomatic, making it easily missed, particularly in young children who cannot articulate hearing difficulties 2
• The condition can be present without any complaints from the child or parent 1

Impact on Development and Quality of Life

• Persistent OME can significantly affect child development and quality of life, particularly when bilateral hearing loss is present 2
• Impairment of speech and language development, school performance, and behavioral development 2

Epidemiology

• Approximately 90% of children experience at least one episode of OME by age 2 years 1
• Over 50% of children experience OME in their first year of life, and more than 60% by age 2 years 2
• Approximately 80% of children will have had at least one episode by age 10 2
• The natural history is generally favorable, with most episodes resolving spontaneously within 3 months 2
• However, 30-40% of children have repeated episodes, and 25% of episodes persist for ≥3 months 2

Diagnosis

Essential Diagnostic Tools

Pneumatic otoscopy is the gold standard for documenting middle ear effusion, showing minimal or sluggish tympanic membrane movement when fluid is present. 1

• Pneumatic otoscopy should be documented when diagnosing OME, with key findings including minimal or sluggish tympanic membrane movement with applied pressure, and presence of middle ear effusion behind an intact tympanic membrane 2
• Tympanometry provides an objective measurement of tympanic membrane mobility and middle ear pressure, and is recommended for diagnosis 1
• Tympanometry should be obtained when the diagnosis is uncertain after pneumatic otoscopy, with a flat or nearly flat tracing indicating middle ear fluid 2

Hearing Assessment

• Hearing assessment should be performed to document the degree of conductive hearing loss 1
• An age-appropriate auditory test is the only assessment required in children without abnormal history 5
• Hearing must be evaluated before and after treatment to not miss another underlying cause of deafness (e.g., sensorineural hearing loss) 3

Additional Evaluation

• A thorough medical examination is necessary to seek reflux, allergy, or nasal obstruction symptoms 5
• Nasal endoscopy is only indicated in cases of unilateral OME or when obstructive adenoid hypertrophy is suspected 3

Treatment and Management

Initial Approach: Watchful Waiting

Watchful waiting is the appropriate initial approach for most cases of OME, as the natural history of the condition is favorable with spontaneous resolution. 1

• This recommendation is emphasized by the American Academy of Otolaryngology-Head and Neck Surgery guidelines 1
• Most episodes resolve spontaneously within 3 months 2

Non-Surgical Treatments

Autoinflation

Autoinflation is the only beneficial, low-risk, and low-cost non-surgical therapy for OME. 5

• Autoinflation is a self-administered technique that aims to ventilate the middle ear and encourage middle ear fluid clearance by providing positive pressure of air in the nose and nasopharynx (using a nasal balloon or other handheld device) 6
• Autoinflation may result in a moderate improvement in quality of life related to otitis media after short-term follow-up 6
• The evidence suggests that autoinflation may slightly reduce the persistence of OME at three months 6
• Most protocols require children to carry out autoinflation two to three times per day, for between 2 and 12 weeks 6

Medications NOT Recommended

There is a clear international recommendation against using steroids, antibiotics, decongestants, or antihistamines to treat OME, because of side effects, cost issues, and no convincing evidence of long-term effectiveness. 5

• Antibiotics: Although antibiotics compared to no treatment may reduce the proportion of children with persistent OME at up to three months, the overall impact on hearing is very uncertain, and long-term effects are unclear 7
• Antibiotics may provide only short-term efficacy, but long-term efficacy is doubtful 8
• In this age of antimicrobial resistance, coupled with the high natural cure rate, routine antimicrobial treatment of OME is not warranted 8
• Nasal steroids, antihistamines, mucokinetic agents, and nasal decongestants are not reliably effective and rarely provide long-term relief 3

Surgical Treatment

Tympanostomy Tubes (Ventilation Tubes)

Decisions to insert tympanostomy tubes should be based on an auditory test but also take into account the child's context and overall hearing difficulties. 5

• The benchmark treatment for OME is placement of tympanostomy tubes (TTs) and (in some cases) adjunct adenoidectomy 3
• Tubes significantly improve hearing and reduce the number of recurrent AOM with effusion while in place 5
• TTs rapidly normalize hearing and effectively prevent the development of cholesteatoma in the middle ear 3
• However, TTs do not prevent progression towards tympanic atrophy or a retraction pocket 3

Adenoidectomy

Adjuvant adenoidectomy should be considered in children over four years of age, and in those with significant nasal obstruction or infection. 5

• Adenoidectomy enhances the effectiveness of tympanostomy tubes 3
• In children with adenoid hypertrophy, adenoidectomy is indicated before the age of 4 but can be performed later when OME is identified by nasal endoscopy 3

Special Circumstances for Antibiotic Use

• Antimicrobial therapy may be useful in selected patients, particularly those with chronic OME (3 months or longer of bilateral effusion or 6 months or longer of unilateral effusion) for whom surgery is being considered 8
• A one-time short course of antibiotic may allow cancellation or at least postponement of a surgical procedure, particularly in spring/summer when one would like to avoid placing tubes in the ears 8

Follow-Up

• Children must be followed up until OME has disappeared completely, so that any complications are not missed 3