What are the guidelines for treating uncomplicated urinary tract infections (UTIs)?

Guidelines for Treating Uncomplicated Urinary Tract Infections (UTIs)

First-line antibiotics for uncomplicated UTIs include nitrofurantoin monohydrate/macrocrystals for 5 days, trimethoprim-sulfamethoxazole for 3 days (if local resistance <20%), or fosfomycin trometamol as a single dose. 1

Diagnosis

• In women, self-diagnosis with typical symptoms (frequency, urgency, dysuria, nocturia, suprapubic pain) without vaginal discharge is usually accurate enough to diagnose an uncomplicated UTI 2
• Urine culture is NOT routinely needed for uncomplicated UTIs in otherwise healthy women 1, 2
• Reserve urine cultures for:
  • Recurrent infections
  • Treatment failures
  • History of resistant organisms
  • Atypical presentation
  • Men (always obtain culture)
  • Adults ≥65 years with comorbidities

First-Line Treatment Options

1. Nitrofurantoin monohydrate/macrocrystals

• Dosage: 100 mg twice daily for 5 days 1, 2
• Advantages:
  • Maintained good activity against E. coli despite decades of use 3, 4
  • Low resistance rates
• Contraindications:
  • Renal impairment (any degree)
  • Last trimester of pregnancy
  • Known pulmonary disease

2. Trimethoprim-sulfamethoxazole (TMP-SMX)

• Dosage: Standard dose for 3 days 1, 2
• Only use if local E. coli resistance is <20% 1
• FDA-approved for UTIs caused by E. coli, Klebsiella, Enterobacter, Morganella morganii, and Proteus species 5

3. Fosfomycin trometamol

• Dosage: Single dose 1, 2
• Comparable efficacy to nitrofurantoin in clinical and microbiological cure rates 6
• May have slightly more adverse events than nitrofurantoin 6

Alternative Treatment Options

1. Cephalexin

• Dosage: 500 mg twice daily for 5-7 days 1
• Consider when first-line agents cannot be used

2. Fluoroquinolones (e.g., levofloxacin, ciprofloxacin)

• Should be reserved for situations where first-line agents cannot be used 1
• Levofloxacin is FDA-approved for uncomplicated UTIs due to E. coli, K. pneumoniae, or S. saprophyticus 7
• Increasing resistance and risk of adverse effects limit their use as first-line agents

Special Populations

Men with UTI

• Always obtain urine culture and susceptibility testing 2
• Consider possibility of urethritis and prostatitis
• First-line antibiotics: trimethoprim, TMP-SMX, or nitrofurantoin for 7 days 2

Older Adults (≥65 years)

• For non-frail older adults without relevant comorbidities:
  • Same first-line antibiotics as younger adults
  • Same treatment durations as younger adults
• Obtain urine culture with susceptibility testing to adjust therapy if needed 2
• Use nitrofurantoin with caution in elderly due to risk of long-term side effects 4

Pregnant Women

• Screen for and treat asymptomatic bacteriuria
• Options include standard short-course treatment or single-dose fosfomycin 1
• Avoid nitrofurantoin in the last trimester of pregnancy 3

Prevention of Recurrent UTIs

• Recurrent UTIs defined as ≥3 in 1 year or ≥2 in 6 months 8
• Non-antibiotic measures:
  • Increased fluid intake
  • Urinating after intercourse if UTIs are related to sexual activity
  • Cranberry products
  • Methenamine hippurate 2
• Antibiotic prophylaxis options:
  • Nitrofurantoin 50-100 mg daily
  • Trimethoprim 100 mg daily
  • Post-coital single dose when UTIs are related to sexual activity 1
• Vaginal estrogen for postmenopausal women 8

Monitoring and Follow-up

• Routine post-treatment urinalysis or cultures are NOT indicated for asymptomatic patients 1
• If symptoms don't resolve by end of treatment or recur within 2 weeks:
  • Obtain urine culture and susceptibility testing
  • Consider alternative diagnosis or complications 1

Common Pitfalls to Avoid

1. Treating asymptomatic bacteriuria (positive culture without symptoms) 8
2. Using fluoroquinolones as first-line therapy
3. Not considering local resistance patterns when prescribing TMP-SMX
4. Inadequate treatment duration (too short or unnecessarily long)
5. Not obtaining cultures in men, treatment failures, or recurrent cases