Acute otitis media (AOM) is an inflammatory process of the middle ear characterized by bulging of the tympanic membrane and the presence of middle ear effusion, caused by a bacterial infection. The most common pathogens are Streptococcus pneumoniae, nontypeable Haemophilus influenzae, and Moraxella catarrhalis. The condition may occur at any age but mainly affects children, peaking between 6 and 18 months of age, presumably due to the decreased length of the eustachian tube and an increased risk of exposure to the culprit organisms.[1] AOM is the most common bacterial illness in children and the one most commonly treated with antibiotics.[2] An estimated 30% of all antibiotics prescribed for children in the United States are prescribed for AOM.[3] Common symptoms include pain, the feeling of the ear being “blocked” (aural fullness), and partial temporary hearing loss. Vertigo is uncommon and should prompt investigation for alternative diagnoses. Nonspecific findings in young children include fever, irritability, reduced activity or expressivity, vomiting, and decreased appetite. Toddlers may be observed tugging on their ear lobes as an indication of inner ear pain. In infants, lethargy can be a sign of a more serious systemic infection.

An upper respiratory infection often precedes AOM, as resultant congestion can obstruct the eustachian tube, creating an accumulation of middle-ear secretions and a potential breeding ground for infections.[4] Spread of infection from the middle ear may result in mastoiditis, resulting in swelling of the jaw or tenderness when palpated, or, uncommonly, facial nerve paralysis, meningitis, or disease of other contiguous structures. Worsening of seasonal allergic rhinitis can predispose to AOM in adults.[1]

Risk Factors

AOM incidence peaks during the winter months[2]. Seasonal allergic rhinitis may contribute in the spring or fall.

The following factors are associated with risk for AOM:

Age < 10 years. Peak is between 6 months and 18 months.[1]

Pacifier use.[5] Bottle feeding, used in place of breastfeeding, may also increase risk, as noted below.

Recent upper respiratory infection.

Day care attendance.[5]

Tobacco smoke exposure.[6]

Air pollution.[7]

Hereditary factors.[5]

Low socioeconomic status.[8]

Immunologic diseases.

Diagnosis

The most specific sign of AOM is a bulging tympanic membrane, but diagnosis requires a sudden onset of ear pain (or evidence of discomfort), erythema of the tympanic membrane, and a middle-ear effusion.[2] An effusion can be demonstrated by a bulging and immobile tympanic membrane. Decreased mobility can also be demonstrated with pneumatic otoscopy. An air-fluid level, or otorrhea (if there is a perforation in the tympanic membrane), can indicate fluid in the middle ear.[9] Otorrhea and a particularly tender ear canal, however, are commonly observed in cases of acute otitis externa rather than otitis media. Tympanometry or acoustic reflectometry may substitute for pneumatic otoscopy when the presence of middle-ear effusion is equivocal.

Bacterial culture of a middle-ear aspirate may be indicated in the case of immunosuppression, severe illness (with AOM as the likely source), or refractory AOM.

Treatment

Nutritional considerations should be made early in the treatment of AOM, as they may reduce the need for other treatments, which can often be difficult and taxing, especially in younger patients.

Decongestants and antihistamines have no proven benefit in AOM.[10]

The immediate treatment goal is controlling pain (otalgia). Several treatment options are available.

Nonsteroidal anti-inflammatory drugs and acetaminophen have been shown to improve symptoms.[11] Caution must be taken with acetaminophen in children as there is a narrower therapeutic window for patients < 2 years of age, and consequently a higher risk of accidental overdose. Occasionally, opioids may be warranted for severe pain that is inadequately controlled with initial analgesic therapy.[12]

The American Academy of Pediatrics and the American Academy of Family Physicians make the following recommendations regarding use of antibiotics for AOM:[2],[10]

• All patients under 6 months of age should receive antibiotics, even if the diagnosis of AOM is uncertain, to prevent complications such as mastoiditis.
• Patients aged 6 months to 2 years should receive antibiotics if the diagnosis is clear. If the diagnosis is uncertain, antibiotics should be given if otalgia is moderate to severe, if otalgia lasts more than 48 hours, if AOM is bilateral, or if the patient’s temperature is ≥ 39°C (102.2°F). Otherwise, observation may be considered.
• Patients older than 2 years with a definite diagnosis of AOM should start an antibiotic if otalgia is moderate to severe or if fever reaches 39°C. Otherwise, observation may be considered.
• Observation alone is permissible only if rapid initiation of antibiotics and follow-up can be guaranteed. Two-thirds of infected children will recover in about 24 hours without the need for antibiotics, but antibiotics should be started if no improvement occurs in 2-3 days.[13],[10][14]
• Amoxicillin, 90 mg/kg divided into 2 doses for 10 days, is the first-line therapy.
• For patients with penicillin allergies, cephalosporins may be used, provided patients did not develop hives or anaphylaxis with penicillin (cross reaction).[15]Macrolides or trimethoprim-sulfamethoxazole may also be used, but endemic bacteria are often resistant to these medications.
• Amoxicillin/clavulanate is used in certain regions with increased resistance or when broader coverage is desired.

Recurrent ear infections, defined as 3 or more episodes in 6 months or 4 episodes in 1 year, may warrant additional treatments.[14] These include tympanostomy with pressure equalization tube placement, and adenoidectomy (to improve eustachian tube function).

Tympanostomy with pressure equalization tube placement is indicated for recurrent AOM or persistent serous effusion causing hearing loss.

Adenoidectomy may benefit those who have recurrent AOM despite tympanostomy. Adenoidectomy may also reduce future AOM episodes when it occurs concomitantly with tympanostomy.[16]

Probiotic interventions may significantly decrease in AOM episodes.[17]

Children suspected of having AOM should be evaluated by an otolaryngologist if they also have developmental delay, established hearing loss, or anatomic variants.

Nutritional Considerations

Breastfeeding. Evidence suggests that breastfeeding for at least 6 months is protective against AOM.[2],[18]

Cow’s milk. Introducing cow’s milk before 4 months may increase risk of AOM.[19]

Allergies. Although most AOM follows a viral upper respiratory infection, food and other environmental allergies can lead to chronic otitis media in 35% to 40% of cases.[20] Diets that eliminate foods suspected of causing allergy have resulted in improvement in 86% of affected children, and most relapse when the offending foods are reintroduced.[9] These occurrences may be related to immunoglobulin G food antigen complexes, particularly those of cow’s milk protein.[21] A cohort study with 260 children found that those with cow’s milk allergy experienced significantly more recurrent otitis media.[22]

Nutritional status. Some children with AOM have evidence of poor antioxidant status, suggesting that inadequate nutritional status may increase risk or prolong the condition.[23],[24] Specifically, low zinc, iron, vitamin A, and vitamin D levels are associated with AOM, and micronutrient supplementation in populations with poor nutrition has shown to be beneficial.[25],[26],[27] Antioxidant-rich and nutrient-dense fruits and berries may be protective.[28]

Orders

See Basic Diet Orders chapter. A plant-based (dairy-free) diet may be helpful.

Consider an elimination diet to wean out potential culprits. For guidelines, see Anaphylaxis and Food Allergy chapter.

What to Tell the Family

The risk of acute otitis media can be reduced by breastfeeding, avoiding crowded environments (such as day care facilities), preventing exposure to tobacco smoke and food allergens, eliminating dairy products, refraining from the use of pacifiers, administering age-appropriate vaccines including Haemophilus influenza type B, Pneumococcal and Influenza vaccines (HiB, either typeable or not and Streptoccocus pneumoniae remain the most common bacterial causes), and providing a diet with adequate micronutrients to support immune function.[2],[29] Antibiotic therapy, while common, is not always necessary. Recommendations for antibiotic use are based on age, severity, and signs and symptoms of a bacterial infection. Repeated episodes of infection may require surgery.

References