Treatment of Symptomatic Urine Colonization
Do not treat asymptomatic bacteriuria (urine colonization) in most patients, as treatment provides no benefit and increases antimicrobial resistance. 1
Key Distinction: Symptomatic vs Asymptomatic
The term "symptomatic urine colonization" is contradictory—if a patient has urinary symptoms (dysuria, frequency, urgency, fever), this represents infection requiring treatment, not colonization. 1 True colonization is asymptomatic and should not be treated in the vast majority of cases.
When to Treat Asymptomatic Bacteriuria (True Colonization)
Only two populations benefit from treating asymptomatic bacteriuria:
- Pregnant women: Treat with standard short-course antibiotics or single-dose fosfomycin trometamol 1
- Before urological procedures breaching the mucosa: Screen and treat prior to instrumentation 1
Do NOT treat asymptomatic bacteriuria in:
- Non-pregnant women with recurrent UTIs 1
- Elderly patients 1
- Patients with indwelling catheters 1
- Kidney transplant recipients (multiple RCTs showed no benefit and increased resistance) 1
- Patients before cardiovascular surgery 1
Treatment of Symptomatic UTI (Actual Infection)
If the patient has true symptoms indicating infection rather than colonization:
First-Line Antibiotics for Uncomplicated Cystitis:
- Nitrofurantoin: 100 mg twice daily for 5 days 1
- Fosfomycin trometamol: 3 g single dose 1
- Trimethoprim-sulfamethoxazole: 160/800 mg twice daily for 3 days (only if local resistance <20%) 1, 2
Duration:
Treat for as short a duration as reasonable, generally no longer than 7 days for symptomatic episodes. 1 For uncomplicated cystitis in women, 3-5 days is typically sufficient. 1
Special Populations:
Candida in urine (candiduria):
- If asymptomatic with catheter: Remove catheter, do not treat 1
- If symptomatic cystitis: Fluconazole 200 mg daily for 2 weeks 1
- If symptomatic pyelonephritis: Fluconazole 200-400 mg daily for 2 weeks 1
Neurogenic bladder patients:
- Treat only symptomatic infections or those with stone-forming organisms 3
- Asymptomatic bacteriuria should not be treated despite high colonization rates 3
Critical Pitfalls to Avoid
The most common error is treating asymptomatic bacteriuria based solely on positive urine culture. 1 This leads to:
- Increased antimicrobial resistance 1
- No reduction in symptomatic UTI rates 1
- Potential adverse drug effects without benefit 1
Pyuria alone does not indicate infection—it is commonly present without infection, especially in elderly patients and those with catheters. 4 Treatment decisions must be based on symptoms, not laboratory findings alone. 1, 4
Obtain urine culture before initiating treatment in patients with recurrent UTIs to guide appropriate antibiotic selection and document true infection versus colonization. 1