What are the recommended treatments for uncomplicated urinary tract infections (UTIs)?

Treatment of Uncomplicated Urinary Tract Infections

For uncomplicated UTIs in women, use nitrofurantoin 100 mg twice daily for 5 days as first-line therapy, with fosfomycin 3 g single dose or trimethoprim-sulfamethoxazole 160/800 mg twice daily for 3 days as alternatives based on local resistance patterns. 1, 2

First-Line Treatment Options for Women

The choice of antibiotic depends critically on local resistance patterns and recent antibiotic exposure:

• Nitrofurantoin monohydrate/macrocrystals 100 mg twice daily for 5-7 days is the preferred first-line agent due to minimal resistance rates and low collateral damage to normal flora 1, 2, 3

• Fosfomycin trometamol 3 g as a single oral dose offers excellent convenience and is FDA-approved specifically for uncomplicated cystitis in women, though efficacy may be slightly lower than nitrofurantoin 1, 2, 4, 3

• Trimethoprim-sulfamethoxazole 160/800 mg twice daily for 3 days should only be used if local E. coli resistance rates are documented to be <20% AND the patient has not used this antibiotic for UTI in the previous 3 months 1, 2, 5, 3

• Pivmecillinam 400 mg three times daily for 3-5 days is an option where available, but avoid if early pyelonephritis is suspected 2

Treatment Duration

Treat for the shortest effective duration—generally 3-7 days maximum—to minimize adverse effects and resistance development. 1

• Nitrofurantoin: 5-7 days 1, 2
• Fosfomycin: Single dose 1, 2, 4
• Trimethoprim-sulfamethoxazole: 3 days 1, 3
• Trimethoprim alone: 3 days 6

Agents to Avoid or Use with Caution

Fluoroquinolones (ciprofloxacin, levofloxacin) should NOT be used for uncomplicated cystitis despite their high efficacy, because they cause significant collateral damage to normal flora, promote resistance, and should be reserved for more serious infections like pyelonephritis 1, 2

β-lactam agents (amoxicillin-clavulanate, cephalosporins) are inferior to first-line agents with lower efficacy and more adverse effects, and should only be used when other options cannot be tolerated 1

Amoxicillin or ampicillin alone should never be used empirically due to very high worldwide resistance rates among E. coli 1

Treatment for Men with Uncomplicated UTI

Men require longer treatment courses—7 days minimum—and should always have urine culture performed before initiating therapy. 2, 6

• Trimethoprim-sulfamethoxazole 160/800 mg twice daily for 7 days is the recommended first-line agent 2
• Nitrofurantoin 100 mg twice daily for 7 days is an alternative 6
• Trimethoprim alone for 7 days can be used 6

Important caveat: Consider urethritis and prostatitis in the differential diagnosis for men presenting with UTI symptoms, as these require different management 6

When to Obtain Urine Culture

Do NOT routinely obtain urine cultures for straightforward uncomplicated cystitis in women. 2, 6

Obtain urine culture and susceptibility testing in these specific situations:

• Suspected pyelonephritis (fever, flank pain, systemic symptoms) 2
• Symptoms that don't resolve or recur within 2-4 weeks after treatment 2, 6
• Atypical symptoms or presentation 2, 6
• Pregnant women (always culture) 2
• History of resistant organisms 1, 6
• All men with UTI symptoms 6
• Recurrent UTIs (≥3 episodes per year or ≥2 in 6 months) 1, 2

Clinical Decision Algorithm

1. Confirm diagnosis clinically in women: Presence of dysuria, frequency, urgency, suprapubic pain WITHOUT vaginal discharge is sufficient for diagnosis without testing 6

2. Assess resistance risk factors:

   • Recent antibiotic use (within 3 months) 2
   • Recent hospitalization or healthcare exposure
   • Known history of resistant organisms 1
   • Local resistance patterns for trimethoprim-sulfamethoxazole 1, 2

3. Select antibiotic based on risk stratification:

   • Low resistance risk: Nitrofurantoin, fosfomycin, or trimethoprim-sulfamethoxazole 1, 2
   • High resistance risk or recent antibiotic use: Nitrofurantoin or fosfomycin 2
   • Renal impairment: Avoid nitrofurantoin if CrCl <30 mL/min; use fosfomycin 2

4. Prescribe shortest effective duration as outlined above 1

Asymptomatic Bacteriuria

Do NOT treat asymptomatic bacteriuria except in pregnant women or patients scheduled for invasive urologic procedures that will injure the urinary tract mucosa. 1, 2

Do NOT perform surveillance urine testing in asymptomatic patients with history of recurrent UTIs. 1

This is a critical pitfall—treating asymptomatic bacteriuria leads to unnecessary antibiotic exposure, adverse effects, and promotes resistance without clinical benefit 1

Follow-Up Recommendations

Routine post-treatment urinalysis or urine cultures are NOT indicated for asymptomatic patients after treatment. 2

For treatment failure or early recurrence (within 2 weeks): Obtain urine culture with susceptibility testing and retreat with a 7-day course of a different agent based on culture results 2

Key Pitfalls to Avoid

• Do not use fluoroquinolones for simple cystitis—reserve these for pyelonephritis or complicated infections 1, 2
• Do not treat asymptomatic bacteriuria in non-pregnant patients 1, 2
• Do not use trimethoprim-sulfamethoxazole without considering local resistance patterns—if >20% resistance in your community, choose a different agent 1, 2
• Do not prescribe amoxicillin or ampicillin empirically—resistance rates are too high 1
• Do not undertreated men—they require 7 days minimum, not 3 days 2, 6
• Do not forget to consider alternative diagnoses in men (urethritis, prostatitis) and women with atypical presentations 6