Treatment of Urinary Tract Infection
For symptomatic uncomplicated UTI, use first-line antibiotics: nitrofurantoin (100 mg twice daily for 5 days), trimethoprim-sulfamethoxazole (160/800 mg twice daily for 3 days), or fosfomycin (3 g single dose), with treatment duration no longer than 7 days. 1
First-Line Antibiotic Selection
The choice among first-line agents should be guided by your local antibiogram and resistance patterns 1:
- Nitrofurantoin: 50-100 mg four times daily OR 100 mg twice daily for 5 days 1
- Trimethoprim-sulfamethoxazole (TMP-SMX): 160/800 mg twice daily for 3 days 1, 2
- Fosfomycin trometamol: 3 g single dose (recommended only for women with uncomplicated cystitis) 1, 2
- Pivmecillinam: 400 mg three times daily for 3-5 days (where available) 1
Key consideration: TMP-SMX should only be used if local E. coli resistance is <20%, as increasing resistance rates have compromised its reliability in many communities 1, 3, 2. Fluoroquinolones (ciprofloxacin, levofloxacin) should be reserved as second-line agents due to collateral damage concerns and resistance preservation 1, 3.
Treatment Duration
Treat for the shortest reasonable duration, generally no longer than 7 days 1. Single-dose antibiotics are associated with higher bacteriological persistence rates (RR 2.01 for short course, RR 1.93 for long course) and should be avoided except for fosfomycin 1.
Diagnostic Approach
Obtain urine culture and sensitivity testing before initiating treatment in patients with recurrent UTIs 1. For first-time uncomplicated cystitis in otherwise healthy women, diagnosis can be made clinically without office visit or culture 2. However, culture is mandatory in these situations 1:
- Suspected acute pyelonephritis
- Symptoms not resolving or recurring within 4 weeks after treatment completion
- Atypical symptoms
- Pregnancy
- Recurrent UTI patients (to guide therapy and establish baseline patterns) 1
Alternative and Second-Line Options
If first-line agents are contraindicated or ineffective 1, 3:
- Cephalosporins (cefadroxil 500 mg twice daily for 3 days, cefpodoxime, ceftibuten): Use only if local E. coli resistance <20% 1
- Trimethoprim alone: 200 mg twice daily for 5 days (avoid in first trimester pregnancy) 1
- β-lactams (amoxicillin-clavulanate): Less effective as empirical first-line therapy 2
Treatment in Men
Men with UTI require 7 days of treatment with TMP-SMX 160/800 mg twice daily 1. Fluoroquinolones can be prescribed according to local susceptibility testing 1. Limited observational data support 7-14 days of therapy for acute UTI in men 2.
Resistant Organisms
For culture-proven resistance to oral antibiotics, use culture-directed parenteral antibiotics for as short a course as reasonable, generally no longer than 7 days 1. Treatment options for ESBL-producing organisms include nitrofurantoin, fosfomycin, pivmecillinam, and carbapenems 3.
Critical Pitfalls to Avoid
Do not treat asymptomatic bacteriuria 1. This is a strong recommendation as treatment fosters antimicrobial resistance and increases recurrent UTI episodes 1. Exceptions are pregnant women and patients scheduled for invasive urinary procedures 1.
Do not perform surveillance urine testing in asymptomatic patients with recurrent UTIs 1. Without symptoms, any magnitude of bacteriuria is considered asymptomatic and should not be treated 1.
Avoid classifying recurrent UTI patients as "complicated" unless they have structural/functional urinary tract abnormalities, immunosuppression, or pregnancy, as this leads to unnecessary broad-spectrum antibiotic use 1.
Immediate vs. Delayed Treatment
Immediate antimicrobial therapy is recommended rather than delayed treatment or symptom management with ibuprofen alone 2. While symptomatic therapy with NSAIDs may be considered for mild-moderate symptoms in consultation with patients, this approach requires careful patient selection 1.
Special Populations
Women with diabetes and no voiding abnormalities should be treated identically to women without diabetes 2. Postmenopausal women with recurrent UTI should receive vaginal estrogen therapy as prevention 1.