Practice recommendations
- High-dose amoxicillin (80 to 90 mg/kg/d divided twice daily) remains the drug of choice for treatment of acute otitis media despite increasing antimicrobial resistance. (B)
- For persistent or recurrent acute otitis media, guidelines recommend high-dose amoxicillin/clavulanate (90/6.4 mg/kg/d), cefdinir, cefprozil, cefpodoxime, cefuroxime or ceftriaxone.(B)
- Increasing the dose of amoxicillin does not cover infection with β-lactamase-producing pathogens; add the β-lactamase inhibitor clavulanate to amoxicillin, or choose a cephalosporin with good activity against S pneumoniae and good β-lactamase stability.(A)
- Key factors for enhancing compliance are taste of suspension, dosing frequency, and duration of therapy. (B)
Empiric treatment of acute otitis media (AOM) should target Streptococcus pneumoniae, nontypeable Haemophilus influenzae, and Moraxella catarrhalis—these bacteria are most often isolated in AOM.1 Group A streptococci and Staphylococcus aureus are involved less often.1 Viruses are the sole AOM pathogen in fewer than 10% of cases; Mycoplasma pneumoniae and Chlamydia pneumoniae rarely cause AOM.
Amoxicillin, 80 to 90 mg/kg/d divided twice daily, remains the drug of choice for AOM despite increasing antimicrobial resistance. Over-diagnosis of AOM and frequent spontaneous resolution of true AOM make amoxicillin the most cost-effective agent. For persistent or recurrent AOM, guidelines recommend high-dose amoxicillin/clavulanate, 90/6.4 mg/kg/d, cefdinir, cefprozil, cefpodoxime, cefuroxime, or ceftriaxone. When the diagnosis is uncertain or the child is older than 2 years, observation may be an option.
The American Academy of Pediatrics and the American Academy of Family Physicians (AAP/AAFP) guideline for management of AOM has several new recommendations that could influence antimicrobial choices for AOM. Among them are use of cephalosporins for non-anaphylaxis penicillin-allergic patients, and regard for such compliance factors as product taste, dosing frequency, and length of therapy.
Pertinent guidelines
The Drug-Resistant Streptococcus pneumoniae (DRSP) Therapeutic Working Group sponsored by the Centers for Disease Control and Prevention (CDC) published recommendations for the management of AOM in 1999.2 A guideline on the treatment of persistent and recurrent AOM based on the recommendations made by the CDC were published by a Clinical Advisory Committee in 2000.3 The AAFP and AAP published a new guideline in 2004.4
What the guidelines agree on
AOM may be difficult to diagnose. The history and symptoms are neither sensitive nor specific enough to make an accurate diagnosis of AOM.5,6 Although various definitions of AOM have been proposed, all agree that AOM is a diagnosis based on visualization of the tympanic membrane and assessment of middle-ear fluid status. Certain physical signs, including bulging of the tympanic membrane, distortion of the light reflex, redness, and disappearance of the translucency of the tympanic membrane are typical of AOM (FIGURE 1).7
AOM must be differentiated from OME. It is crucial to distinguish between AOM and otitis media with effusion (OME) because OME is usually not treated with antimicrobials.7 This is a clinical conundrum because OME often precedes and follows AOM (FIGURE 1).
Although OME is considered asymptomatic except for hearing loss, it is now known to cause mild to moderate otalgia associated with tympanic membrane stretching.1,3,7 Ear tugging and poor sleep follow.
The optimal physical finding to differentiate OME from AOM is tympanic membrane position. Patients with AOM have a bulging tympanic membrane; those with OME have a neutral or retracted tympanic membrane (FIGURE 1). Tympanic membrane position is best assessed with pneumatic otoscopy.1,3,7
Tympanocentesis usually necessary. All guidelines advocate that physicians either learn the skills needed to perform tympanocentesis, or refer patients to a clinician who can perform the procedure when 2 sequential treatment failures occur and for other indications.2-4 In cases of persistent or recurrent AOM, tympanocentesis with a culture of the middle-ear fluid may be especially useful in guiding treatment. In addition, evacuation of the middle-ear effusion can be helpful in breaking the cycle of persistent and recurrent AOM.
Criteria for choosing an antimicrobial. The most important consideration in selecting an antimicrobial is efficacy against S pneumoniae. Although this pathogen as a cause of AOM is decreasing in the wake of widespread use of the 7-valent pneumococcal conjugate vaccine,8 it is also the least likely of the 3 main pathogens to resolve spontaneously without treatment.2,9
All guidelines also recommend that the selected antibiotic have efficacy against β-lactamase-producing strains of H influenzae and M catarrhalis.
S pneumoniae with reduced susceptibility to penicillin, and H influenzae that produce β-lactamase, are significantly more prevalent among children than adults, especially among children who attend day care, who have received antimicrobials within the preceding month, or who have not responded to recent treatment.2,3 An antimicrobial chosen empirically must not only have activity against the major pathogens, but it must also achieve a peak concentration in the middle-ear fluid sufficient to eradicate S pneumoniae with reduced susceptibility to penicillin and retain activity if β-lactamase is produced by a gram-negative organism.