Treatment of Urinary Tract Infections
For acute uncomplicated UTI in women, use first-line therapy with nitrofurantoin, trimethoprim-sulfamethoxazole (TMP-SMX), or fosfomycin for 3-7 days, with treatment selection based on local antibiogram patterns. 1
First-Line Antibiotic Selection
The three recommended first-line agents are equally effective for clinical and bacteriological cure but differ in their propensity to cause collateral damage (antimicrobial resistance) 1:
- Nitrofurantoin: 100 mg twice daily for 5-7 days 1, 2
- Trimethoprim-sulfamethoxazole: 160/800 mg twice daily for 3 days 1, 2
- Fosfomycin trometamol: 3 g single dose 1, 2
Selection should be guided by local resistance patterns, with TMP-SMX and fluoroquinolones avoided if local resistance exceeds 10-20% or if the patient has recent exposure to these agents. 1
Treatment Duration
- Treat acute cystitis episodes for as short a duration as reasonable, generally no longer than 7 days 1
- Single-dose antibiotics show increased bacteriological persistence compared to 3-6 day courses 1
- For men with UTI, 7-14 days of therapy is recommended based on observational data 2
Diagnostic Approach Before Treatment
Obtain urine culture and sensitivity with each symptomatic acute cystitis episode prior to initiating treatment in patients with recurrent UTIs. 1
For acute uncomplicated cystitis in otherwise healthy women:
- Diagnosis can be made without office visit or culture in straightforward cases 2
- Urinalysis with nitrite dipstick and leukocyte esterase typically suffices 3
- Culture remains the gold standard when needed (>10^5 CFU/mL in symptomatic patients) 3
Patient-Initiated Treatment
Self-start antibiotic therapy may be offered to select reliable patients with recurrent UTI who can obtain urine specimens before starting therapy and communicate effectively with their provider. 1
Second-Line Options
When first-line agents are contraindicated due to resistance or allergy 1:
- Oral cephalosporins (cephalexin, cefixime) 4
- Fluoroquinolones (ciprofloxacin) - only if local resistance <10% 1
- β-lactams (amoxicillin-clavulanate) - less effective as empirical therapy 2
Fluoroquinolones should be reserved for more invasive infections and avoided for empirical treatment in urology patients or those with recent fluoroquinolone exposure in the last 6 months. 1
Complicated UTI Management
For complicated UTIs with systemic symptoms, use empirical broad-spectrum therapy 1:
- Amoxicillin plus aminoglycoside
- Second-generation cephalosporin plus aminoglycoside
- Intravenous third-generation cephalosporin
Treatment duration is 7-14 days (14 days for men when prostatitis cannot be excluded), but may be shortened to 7 days if the patient is hemodynamically stable and afebrile for at least 48 hours. 1
Multidrug-Resistant Organisms
For carbapenem-resistant Enterobacterales (CRE) causing UTI 1:
- Ceftazidime-avibactam 2.5 g IV q8h (weak recommendation) 1
- Meropenem-vaborbactam 4 g IV q8h or imipenem-cilastatin-relebactam 1.25 g IV q6h 1
- Plazomicin 15 mg/kg IV q12h 1
- Single-dose aminoglycoside for simple cystitis due to CRE 1
Critical Pitfalls to Avoid
Do not treat asymptomatic bacteriuria - this fosters antimicrobial resistance and increases recurrent UTI episodes 1. Exceptions are pregnant women and patients scheduled for invasive urinary procedures 1.
Avoid classifying recurrent UTI patients as "complicated" - this leads to unnecessary broad-spectrum antibiotics with prolonged treatment durations 1. Reserve "complicated" designation for structural/functional urinary tract abnormalities, immunosuppression, or pregnancy 1.
Do not perform surveillance urine testing in asymptomatic patients with recurrent UTIs. 1
If persistent symptoms occur despite treatment, repeat urine culture to assess for ongoing bacteriuria before prescribing additional antibiotics 1.
Special Populations
Women with diabetes and acute cystitis without voiding abnormalities should be treated similarly to women without diabetes. 2
For catheter-associated UTI with systemic symptoms, initiate empirical treatment and continue until organism identification and susceptibility results are available 1.