My 5‑year‑old child with acute otitis media has been taking oral cefdinir (14 mg/kg twice daily) for 7 days and still has ear pain; what assessment and treatment should be done?

Treatment Failure After 7 Days of Cefdinir for Acute Otitis Media

Switch immediately to high-dose amoxicillin-clavulanate (90 mg/kg/day of amoxicillin component with 6.4 mg/kg/day of clavulanate, divided twice daily) for 10 days. 1, 2

Confirm True Treatment Failure

Before changing antibiotics, you must verify:

• Reassess the tympanic membrane with pneumatic otoscopy to confirm persistent acute otitis media (bulging membrane, impaired mobility, middle ear effusion with inflammation) rather than post-treatment effusion without acute symptoms 1
• Distinguish AOM from otitis media with effusion (OME): 60-70% of children have persistent middle ear fluid at 2 weeks after successful treatment, which does NOT require antibiotics 1
• Rule out otitis externa: If there is external ear canal erythema, swelling, or drainage with canal tenderness, this represents otitis externa rather than AOM treatment failure 2
• Verify medication compliance: Improper administration is a common cause of apparent treatment failure 2

Why Cefdinir Failed

• Cefdinir has limited coverage against beta-lactamase-producing Haemophilus influenzae and Moraxella catarrhalis, which are the predominant pathogens when first-line therapy fails 2
• Clinical cure rates with cefdinir (71%) are significantly lower than high-dose amoxicillin-clavulanate (86.5%) in head-to-head trials 3
• Cefdinir shows decreasing efficacy as children age from 6-24 months, with cure rates declining with each month of age, whereas amoxicillin-clavulanate maintains stable efficacy 3
• Even at 25 mg/kg/day, cefdinir fails to achieve adequate pharmacodynamic targets against penicillin-nonsusceptible S. pneumoniae 4

First-Line Treatment for This Failure

High-dose amoxicillin-clavulanate is the evidence-based next step:

• Dosing: 90 mg/kg/day of amoxicillin component + 6.4 mg/kg/day of clavulanate, divided into 2 doses daily 1, 2
• Duration: 10 days for a 5-year-old with treatment failure 1
• Rationale: Provides optimal coverage against resistant S. pneumoniae AND beta-lactamase-producing H. influenzae and M. catarrhalis 2
• Twice-daily dosing causes significantly less diarrhea (13%) than three-times-daily dosing (35%) while maintaining equivalent efficacy 1, 5

If Amoxicillin-Clavulanate Fails (48-72 Hours)

Administer intramuscular ceftriaxone 50 mg/kg once daily for 3 consecutive days:

• A 3-day course is superior to a single-dose regimen for AOM unresponsive to initial antibiotics 1
• Ceftriaxone achieves high middle ear fluid concentrations and overcomes resistance mechanisms 2

After Multiple Treatment Failures

• Perform tympanocentesis with culture and susceptibility testing to guide targeted therapy 1, 2
• Consider clindamycin (30-40 mg/kg/day in 3 divided doses) if tympanocentesis is unavailable, but note that clindamycin lacks coverage against H. influenzae and M. catarrhalis, so combination therapy may be needed 2
• Consult infectious disease and otolaryngology specialists before using levofloxacin or linezolid for multidrug-resistant S. pneumoniae serotype 19A 1

Pain Management Throughout

• Continue acetaminophen or ibuprofen at weight-based doses throughout the treatment course, independent of antibiotic changes 1
• Pain relief from analgesics occurs within 24 hours, whereas antibiotics provide no symptomatic benefit in the first 24 hours 1

Critical Pitfalls to Avoid

• Do NOT use trimethoprim-sulfamethoxazole, azithromycin, clarithromycin, or erythromycin-sulfisoxazole for treatment failures—pneumococcal resistance to these agents is substantial (macrolide resistance exceeds 40%, with bacterial failure rates of 20-25%) 1, 2
• Do NOT simply extend the duration of cefdinir—switch to an agent with broader antimicrobial coverage 2
• Do NOT treat persistent middle ear effusion without acute symptoms (no bulging, no pain, no fever) with antibiotics—this is OME and requires monitoring only 1

Follow-Up Protocol

• Reassess within 48-72 hours after starting amoxicillin-clavulanate to verify improvement 1, 2
• Expect persistent effusion: 40% of children still have middle ear fluid at 1 month and 10-25% at 3 months after successful treatment, which is normal and does not require further antibiotics 1
• Consider tympanostomy tube referral if this represents recurrent AOM (≥3 episodes in 6 months or ≥4 episodes in 12 months) 1