What is the recommended treatment for a urinary tract infection (UTI)?

Treatment of Urinary Tract Infections

For acute uncomplicated UTIs in women, use first-line antibiotics: nitrofurantoin for 5 days, trimethoprim-sulfamethoxazole (TMP-SMX) for 3 days, trimethoprim for 3 days, or fosfomycin as a single dose, based on local antibiogram patterns. 1

Acute Uncomplicated UTI Management

Diagnosis and Culture Strategy

• Obtain urine culture and sensitivity testing before initiating treatment in patients with recurrent UTIs (≥2 infections in 6 months or ≥3 in one year) 1
• For first-time uncomplicated UTI in women with typical symptoms (dysuria, frequency, urgency, suprapubic pain) and no vaginal discharge, clinical diagnosis without culture is acceptable 2
• Do NOT obtain surveillance cultures or treat asymptomatic bacteriuria (except in pregnant women or before invasive urologic procedures) 1

First-Line Antibiotic Selection

The choice depends on local resistance patterns and patient-specific factors 1:

• Nitrofurantoin: 5-7 days (preferred when possible due to low resistance rates) 1, 2
• Trimethoprim-sulfamethoxazole: 3 days (avoid if local resistance >20%) 1, 3
• Fosfomycin: Single dose 1
• Trimethoprim: 3 days 2

Treatment Duration

• Treat for as short a duration as reasonable, generally no longer than 7 days 1
• Three-day therapy achieves similar symptomatic cure rates as 5-10 day regimens but with fewer adverse effects 4
• Single-dose antibiotics show higher bacteriological persistence and should be avoided except for fosfomycin 1

Men with Uncomplicated UTI

• Always obtain urine culture and sensitivity testing before treatment 2
• Treat for 7 days minimum with first-line agents: trimethoprim, TMP-SMX, or nitrofurantoin 2
• Consider urethritis and prostatitis as alternative diagnoses 2

Complicated UTI Management

Definition and Risk Factors

Complicated UTIs occur with 1:

• Urinary tract obstruction or foreign bodies (catheters, stents)
• Structural/functional abnormalities
• Male gender
• Pregnancy
• Immunosuppression
• Healthcare-associated infections
• Multidrug-resistant organisms

Treatment Approach

For complicated UTIs with systemic symptoms, initiate empiric broad-spectrum therapy 1:

• Amoxicillin plus aminoglycoside, OR
• Second-generation cephalosporin plus aminoglycoside, OR
• Intravenous third-generation cephalosporin 1

Avoid fluoroquinolones for empiric treatment if local resistance >10%, patient used fluoroquinolones in last 6 months, or patient is from urology department 1

Duration for Complicated UTI

• 7-14 days is generally recommended (14 days for men when prostatitis cannot be excluded) 1
• Shorter duration (7 days) may be considered when patient is hemodynamically stable and afebrile for ≥48 hours with adequate source control 1

Catheter-Associated UTI

• Only treat symptomatic CA-UTI (fever, rigors, altered mental status, flank pain, costovertebral angle tenderness) 1
• Initiate empiric broad-spectrum antibiotics against Enterobacteriaceae and Enterococci 1
• Short-course therapy (3-5 days) with early re-evaluation is recommended even in critically ill patients with adequate source control 1

Recurrent UTI Prevention

Postmenopausal Women

• Vaginal estrogen with or without lactobacillus-containing probiotics as first-line prevention 1
• Oral estrogen does NOT appear beneficial 1

Premenopausal Women

For post-coital infections:

• Low-dose antibiotic within 2 hours of sexual activity for 6-12 months 1
• Preferred agents: nitrofurantoin 50 mg, TMP-SMX 40/200 mg, or trimethoprim 100 mg 1

For infections unrelated to sexual activity:

• Daily antibiotic prophylaxis is most effective (reduces UTI rate to 0.4/year) 1

Non-Antibiotic Alternatives

• Methenamine hippurate and/or lactobacillus-containing probiotics for patients desiring non-antibiotic options 1
• Cranberry products may provide modest benefit 1, 2
• Increased fluid intake 2

Multidrug-Resistant Organisms

Carbapenem-Resistant Enterobacteriaceae (CRE)

For complicated UTI due to CRE 1:

• Ceftazidime-avibactam 2.5 g IV q8h, OR
• Meropenem-vaborbactam 4 g IV q8h, OR
• Imipenem-cilastatin-relebactam 1.25 g IV q6h, OR
• Plazomicin 15 mg/kg IV q12h 1

For simple cystitis due to CRE:

• Single-dose aminoglycoside may be considered 1

Critical Pitfalls to Avoid

• Never treat asymptomatic bacteriuria in non-pregnant patients—this increases resistance and recurrence rates 1
• Avoid classifying recurrent UTI as "complicated" unless true complicating factors exist—this leads to unnecessary broad-spectrum antibiotic use 1
• Do not use fluoroquinolones empirically for serious complicated UTIs when resistance risk factors are present 1, 5
• Obtain culture before treatment in recurrent UTI, treatment failure, or resistant organism history 1
• If symptoms persist despite treatment, repeat urine culture before prescribing additional antibiotics 1