Emergency Department Workup for Suspected UTI
For patients with suspected urinary tract infection (UTI) in the emergency department, obtain a urine culture and initiate empirical broad-spectrum antibiotic therapy against Enterobacteriaceae and Enterococci, with subsequent modification based on culture results. 1
Diagnostic Approach
- Obtain a urine culture before initiating antibiotic therapy to guide subsequent treatment decisions 1, 2
- Perform urinalysis with dipstick testing to assess for pyuria (leukocyte esterase positive or >5 white blood cells per high-power field) 3, 2
- Urine flow cytometry (UFC) and urine dipstick analysis (UDA) can help rule out UTI with high negative predictive values (97.0% and 93.9% respectively) 2
- CT urography with both nephrographic and excretory phases is the gold standard diagnostic exam if there is concern for complicated UTI or urinary tract injury 1
- Serum inflammatory markers (e.g., C-reactive protein) may be elevated in cases of pyelonephritis or complicated UTI 1
Collection Technique
- Proper midstream clean-catch technique is important for valid results but is frequently not performed correctly in emergency settings 4
- Instruct patients to collect midstream urine and part the labia (for women) to minimize contamination 4
- Consider catheterization for patients unable to provide a reliable clean-catch specimen 3
Treatment Recommendations
Uncomplicated UTI in Women
First-line treatments: 1
- Fosfomycin trometamol 3g single dose
- Nitrofurantoin 100mg twice daily for 5 days
- Pivmecillinam 400mg three times daily for 3-5 days
Alternative treatments: 1
- Cephalosporins (e.g., cefadroxil 500mg twice daily for 3 days) if local E. coli resistance is <20%
- Trimethoprim 200mg twice daily for 5 days (avoid in first trimester of pregnancy)
- Trimethoprim-sulfamethoxazole 160/800mg twice daily for 3 days (avoid in last trimester of pregnancy)
UTI in Men
- Trimethoprim-sulfamethoxazole 160/800mg twice daily for 7 days 1
- Fluoroquinolones (e.g., ciprofloxacin) can be prescribed based on local susceptibility patterns 1, 5
Complicated UTI or Pyelonephritis
- Initiate empirical broad-spectrum antibiotic therapy against Enterobacteriaceae and Enterococci 1
- Ciprofloxacin 500mg twice daily for 7-14 days (mild/moderate) or 750mg twice daily for 7-14 days (severe) 5
- Adjust dose based on patient's weight, renal clearance, and liver function 1
- Short-course antibiotic therapy (3-5 days) with early re-evaluation is recommended if adequate source control is achieved 1
Special Considerations
- For patients with indwelling urinary catheters who develop symptomatic UTI, initiate empiric antibiotics and continue until culture results are available 1
- Empirical antifungal therapy is not recommended for UTI 1
- For patients with recurrent UTIs, consider additional diagnostic evaluation to identify underlying causes 1
- In critically ill patients with signs of sepsis or septic shock, timely antibiotic administration and adequate source control are crucial 1
Common Pitfalls to Avoid
- Treating asymptomatic bacteriuria (except in pregnancy) 3
- Failing to obtain cultures before initiating antibiotics in complicated cases 1
- Prescribing unnecessarily prolonged courses of antibiotics (current practice often results in 10-day courses when shorter durations may be sufficient) 3
- Misdiagnosing UTI when symptoms may be due to other conditions that can mimic UTI presentation 6
- Not modifying empiric therapy based on culture results 1