What is the recommended treatment for a Urinary Tract Infection (UTI)?

Treatment of Urinary Tract Infections

First-Line Antibiotic Therapy

For uncomplicated UTIs in women, use nitrofurantoin 100 mg twice daily for 5 days, fosfomycin 3 g single dose, or trimethoprim-sulfamethoxazole 160/800 mg twice daily for 3 days (only if local resistance <20%). 1

Specific First-Line Recommendations by Patient Population

Women with uncomplicated cystitis:

• Nitrofurantoin 100 mg twice daily for 5 days is the preferred first-line agent due to low resistance rates and minimal collateral damage 1, 2
• Fosfomycin trometamol 3 g single dose is an excellent alternative, particularly for patients who prefer single-dose therapy 1, 2
• Trimethoprim-sulfamethoxazole 160/800 mg twice daily for 3 days can be used only if local resistance rates are documented to be <20% 1, 2
• Trimethoprim 100 mg for 3 days is another option where resistance is low 2

Men with uncomplicated UTIs:

• Treatment duration should be 7 days (longer than women) 1
• Trimethoprim-sulfamethoxazole 160/800 mg twice daily for 7 days is the preferred option 1
• Nitrofurantoin and trimethoprim for 7 days are alternatives 2
• Always obtain urine culture before treatment to guide antibiotic selection 2

Complicated UTIs and pyelonephritis:

• Treatment duration should be 7-14 days 1
• Broader spectrum coverage is required, with consideration of combination therapy for severe cases 1
• For gram-negative bacteremia from a urinary source, 7 days of treatment is recommended 3

Critical Diagnostic Considerations

Obtain urine culture before initiating treatment in these situations:

• Suspected pyelonephritis 1
• Symptoms not resolving within 4 weeks after treatment 1
• Atypical symptoms 1
• Recurrent UTIs 3, 1
• Pregnant women 1
• All men with UTI symptoms 2
• History of resistant isolates or treatment failure 2

For women with typical symptoms (frequency, urgency, dysuria, nocturia, suprapubic pain) without vaginal discharge, clinical diagnosis alone is sufficient without culture 2

Antibiotics to Avoid as First-Line

Do not use fluoroquinolones (ciprofloxacin, levofloxacin) as first-line therapy due to:

• Increasing resistance rates 1, 4
• Risk of serious adverse effects 1
• Need to preserve these agents for more serious infections 4, 5
• High rates of resistance in many communities 4

Do not use nitrofurantoin for suspected pyelonephritis or febrile UTIs because it does not achieve adequate tissue concentrations 1

Avoid single-dose antibiotics except fosfomycin as they are associated with higher rates of bacteriological persistence 1

Duration of Treatment Algorithm

Uncomplicated cystitis in women:

• Nitrofurantoin: 5 days 1, 2
• Fosfomycin: Single 3 g dose 1, 2
• Trimethoprim-sulfamethoxazole: 3 days 1, 2
• Trimethoprim: 3 days 2

Uncomplicated UTI in men:

• All first-line agents: 7 days 1, 2

Pyelonephritis:

• Fluoroquinolones (ciprofloxacin or levofloxacin): 5-7 days 3
• Beta-lactams: 7 days 3
• Trimethoprim-sulfamethoxazole: 7 days (though 14 days was historically used) 3

Complicated UTIs:

• 7-14 days depending on severity and response 1

Critical Pitfalls to Avoid

Never treat asymptomatic bacteriuria except in:

• Pregnant women 3, 1
• Patients scheduled for urologic procedures 1
• Treating asymptomatic bacteriuria in women with recurrent UTIs increases antimicrobial resistance and recurrence episodes 3

Do not routinely obtain post-treatment urine cultures in asymptomatic patients 1

Avoid classifying patients with recurrent UTIs as "complicated" as this leads to unnecessary use of broad-spectrum antibiotics with prolonged durations 3

Reserve "complicated UTI" classification for:

• Congenital or acquired structural/functional urinary tract abnormalities 3
• Immunosuppression 3
• Pregnancy 3

If symptoms persist despite treatment, repeat urine culture to assess for ongoing bacteriuria before prescribing additional antibiotics 3

Special Considerations for Recurrent UTIs

For women with recurrent UTIs (>2 culture-positive UTIs in 6 months or >3 in one year):

Postmenopausal women:

• Initiate vaginal estrogen with or without lactobacillus-containing probiotics 3
• Oral estrogen does not appear beneficial 3

Premenopausal women with post-coital infections:

• Low-dose antibiotic within 2 hours of sexual activity for 6-12 months 3
• Preferred agents: nitrofurantoin 50 mg, trimethoprim-sulfamethoxazole 40/200 mg, or trimethoprim 100 mg 3

Premenopausal women with infections unrelated to sexual activity:

• Low-dose daily antibiotic prophylaxis 3
• Consider rotating antibiotics at 3-month intervals to avoid resistance 3

Non-antibiotic alternatives for all groups:

• Methenamine hippurate 3, 2
• Lactobacillus-containing probiotics 3
• Cranberry products 2

When selecting prophylactic antibiotics, prioritize nitrofurantoin, trimethoprim-sulfamethoxazole, or trimethoprim over fluoroquinolones and cephalosporins 3

Symptomatic Treatment and Delayed Antibiotic Approach

Consider symptomatic treatment with NSAIDs and delayed antibiotics because:

• The risk of uncomplicated UTI progressing to pyelonephritis is low (1-2%) 6, 2
• Presence of bacteria in the bladder allows time for immune system response 6
• This approach reduces antibiotic consumption and resistance 6

Increased fluid intake can help prevent recurrent infections 2