Management of Persistent Sore Throat After Completed Amoxicillin Course in Elderly Female with Ill-Fitting Dentures
Do not extend the amoxicillin course; instead, immediately reassess for alternative diagnoses, particularly denture-related oral candidiasis and mechanical trauma from ill-fitting dentures, and only switch to a different antibiotic class if bacterial pharyngitis is confirmed on re-examination. 1
Immediate Clinical Reassessment Required
The failure to respond to a complete course of amoxicillin indicates either treatment failure, chronic GAS carriage with intercurrent viral infection, or—most likely in this elderly patient with poorly fitting dentures—an alternative diagnosis entirely. 1 You must:
Examine the oral cavity thoroughly for denture stomatitis (chronic candidiasis), which presents as erythema and soreness under dentures and is the most common cause of "denture sore mouth" in elderly patients. 2 This would not respond to antibiotics and requires antifungal therapy.
Assess for mechanical ulceration or hyperplasia from the ill-fitting dentures, as improperly fitting dentures cause ulcers, stomatitis, and chronic irritation that mimics infectious pharyngitis. 2
Rule out suppurative complications including peritonsillar abscess, cervical lymphadenitis, or acute otitis media, as these require different management than simple antibiotic switching. 1
Evaluate fever pattern: persistent fever beyond 3 days of appropriate antibiotic therapy strongly suggests true bacterial infection requiring antibiotic change rather than viral illness or non-infectious causes. 1
Why Extending Amoxicillin Is Not Appropriate
Extending the same antibiotic that has already failed is not evidence-based. The standard amoxicillin course for pharyngitis is 10 days, which she has completed. 3
If bacterial pharyngitis were present and susceptible to amoxicillin, clinical improvement should have occurred within 48-72 hours. 3 The absence of improvement after a full course indicates either resistance, wrong diagnosis, or non-bacterial etiology.
Prolonging ineffective antibiotic therapy increases antimicrobial resistance risk and adverse effects without clinical benefit. 3
Most Likely Diagnosis: Denture-Related Pathology
Given the prominent history of ill-fitting dentures in an elderly female with persistent oral symptoms despite negative tests and completed antibiotics:
Chronic candidiasis (denture stomatitis) is the most probable diagnosis, as it develops under improperly fitting dentures and causes persistent soreness that does not respond to antibacterial therapy. 2
Mechanical trauma from dentures causes ulcers and chronic irritation that can persist indefinitely until the denture fit is corrected. 2
Appropriate Management Algorithm
Step 1: Confirm or Exclude Bacterial Pharyngitis
If the patient has fever, tonsillar exudates, tender cervical adenopathy, and absence of cough, consider bacterial pharyngitis and proceed to Step 2. 3
If the patient has cough, nasal congestion, or oral lesions (ulcers/vesicles), this suggests viral illness or denture-related pathology—do not prescribe antibiotics. 3
Step 2: If Bacterial Pharyngitis Is Confirmed
Switch antibiotic classes to a macrolide (azithromycin 500 mg once daily for 5 days) or first-generation cephalosporin (cephalexin 500 mg twice daily for 10 days) if no anaphylactic penicillin allergy. 1
Evaluate response after 48 hours of new antibiotic therapy; if no improvement after 5 days, consider alternative diagnoses or specialist referral. 1
Step 3: If Denture-Related Pathology Is Suspected (Most Likely)
Prescribe topical antifungal therapy (nystatin oral suspension 400,000-600,000 units swish and swallow four times daily, or clotrimazole troches 10 mg five times daily) for presumed denture stomatitis. 2
Refer to dentistry urgently for denture adjustment or replacement, as the underlying mechanical problem must be corrected for resolution. 2
Instruct the patient to remove dentures at night and clean them thoroughly with denture cleanser to reduce fungal colonization. 2
When to Consider Specialist Referral
Refer to otolaryngology if worsening symptoms despite appropriate antibiotic changes, development of suppurative complications, or inability to maintain oral hydration. 1
Refer to dentistry immediately for denture adjustment, as extensive bone resorption can occur under improperly fitting dentures and may eventually require dental implants. 2
Consider infectious disease consultation if multiple antibiotic failures occur and bacterial infection is strongly suspected, as this may require unconventional therapy. 3
Critical Pitfalls to Avoid
Do not prescribe more amoxicillin without confirming bacterial infection, as this contributes to resistance and delays correct diagnosis. 3, 1
Do not overlook the denture history, as mechanical and fungal complications from ill-fitting dentures are extremely common in elderly patients and will not respond to antibiotics. 2
Do not assume chronic GAS carriage requires treatment, as carriers are at low risk for complications and spreading disease, and routine eradication is not indicated. 3, 1
Be aware that malignant changes can develop under chronically ill-fitting dentures, so persistent lesions warrant biopsy if they do not resolve with denture adjustment. 2