Amoxicillin-Clavulanate for UTI in a 92-Year-Old Woman
Amoxicillin-clavulanate (Augmentin) should only be prescribed for this 92-year-old woman if she has symptomatic urinary tract infection with culture-confirmed susceptible organisms, not for asymptomatic bacteriuria.
Assessment of UTI vs. Asymptomatic Bacteriuria
Before prescribing any antibiotic, it's crucial to determine whether the patient has a true UTI requiring treatment or asymptomatic bacteriuria (ASB):
True UTI symptoms to look for:
- Dysuria, frequency, urgency
- Suprapubic pain
- Fever (>38°C)
- Flank pain (if pyelonephritis)
Not sufficient for diagnosis:
- Positive urine culture alone
- Confusion/delirium without other UTI symptoms
- Falls without localizing UTI symptoms
- Pyuria alone
The Infectious Diseases Society of America (IDSA) makes a strong recommendation against treating ASB in older adults, as there is high certainty of harm and low certainty of benefit 1. Treatment of ASB in elderly patients has not been shown to improve outcomes but increases risk of adverse effects including Clostridioides difficile infection and antimicrobial resistance.
Appropriate Use of Amoxicillin-Clavulanate
If the patient has a symptomatic UTI with culture results showing susceptible organisms:
Indications for amoxicillin-clavulanate:
- FDA-approved for UTIs caused by beta-lactamase-producing isolates of E. coli, Klebsiella species, and Enterobacter species 2
- Particularly valuable for resistant organisms 3
Dosing considerations:
- For complicated UTI: 875 mg/125 mg every 12 hours or 500 mg/125 mg every 8 hours 2
- Consider renal dose adjustment in elderly patients
- Duration: 7-14 days for complicated UTIs in elderly women per European Association of Urology 1
Monitoring:
- Assess for gastrointestinal side effects (diarrhea occurs in 14-15% of patients) 2
- Monitor renal function
- Watch for signs of treatment failure
Cautions and Alternatives
If the patient only has asymptomatic bacteriuria:
If the patient has symptomatic UTI but amoxicillin-clavulanate is not appropriate:
- Consider first-line agents for uncomplicated cystitis:
Special Considerations for Elderly Women
- Atypical presentations may occur in elderly patients
- Higher risk of adverse drug reactions
- Increased risk of C. difficile infection with antibiotic use
- Consider vaginal estrogen replacement in postmenopausal women to prevent recurrent UTI 1
- Ensure adequate hydration (1500-2000 ml/day if not contraindicated) 4
Bottom Line
Amoxicillin-clavulanate can be given to a 92-year-old woman with a true, symptomatic UTI caused by susceptible organisms, but should not be used for asymptomatic bacteriuria. The decision must be based on clinical symptoms and culture results, not just the presence of bacteria in urine.