What medication will you give a patient presenting with fever and dysuria?

Treatment of Fever and Dysuria in the Emergency Department

For a patient presenting with fever and painful urination (dysuria), initiate empirical antibiotic therapy immediately with either a fluoroquinolone (ciprofloxacin 400 mg IV twice daily or levofloxacin 750 mg IV once daily) or an extended-spectrum cephalosporin (ceftriaxone 1-2 g IV once daily), as this presentation suggests acute pyelonephritis requiring parenteral treatment. 1

Clinical Assessment and Diagnosis

The combination of fever and dysuria strongly suggests upper urinary tract infection (pyelonephritis) rather than simple cystitis. 1 Key diagnostic steps include:

• Obtain urine culture and antimicrobial susceptibility testing before starting antibiotics - this is mandatory for all suspected pyelonephritis cases 1
• Assess for systemic symptoms: fever >38°C, chills, flank pain, nausea/vomiting, or costovertebral angle tenderness 1
• Perform urinalysis to evaluate white blood cells, red blood cells, and nitrite 1
• Consider imaging (ultrasound) if patient has history of urolithiasis, renal dysfunction, or remains febrile after 72 hours 1

Critical pitfall: Do not rely on urinalysis alone - negative nitrite and leukocyte esterase do not rule out UTI, especially in older patients where specificity ranges only 20-70% 1

Initial Empirical Antibiotic Selection

For Hospitalized Patients (Recommended Approach)

First-line parenteral options for uncomplicated pyelonephritis requiring hospitalization: 1

• Ciprofloxacin 400 mg IV twice daily (only if local fluoroquinolone resistance <10%) 1
• Levofloxacin 750 mg IV once daily 1
• Ceftriaxone 1-2 g IV once daily (higher dose recommended despite lower dose being studied) 1
• Cefotaxime 2 g IV three times daily 1
• Aminoglycoside (gentamicin 5 mg/kg once daily or amikacin 15 mg/kg once daily) with or without ampicillin 1

For Outpatient/Oral Therapy (If Patient Stable)

If the patient is hemodynamically stable, not toxic-appearing, and able to retain oral intake, consider oral therapy: 1

• Ciprofloxacin 500-750 mg orally twice daily for 7 days 1
• Levofloxacin 750 mg orally once daily for 5 days 1
• Trimethoprim-sulfamethoxazole 160/800 mg twice daily for 14 days (if local resistance <10%) 1

Important caveat: If using oral cephalosporins (cefpodoxime 200 mg twice daily or ceftibuten 400 mg once daily for 10 days), administer an initial IV dose of long-acting parenteral antimicrobial (e.g., ceftriaxone) first, as oral cephalosporins achieve significantly lower blood concentrations than IV route 1

Antibiotic Selection Algorithm

Base your choice on these factors in order of priority: 1

1. Local resistance patterns - fluoroquinolones should only be used if local resistance <10% 1
2. Patient severity - toxic appearance, inability to retain oral intake, or hemodynamic instability mandates IV therapy 1
3. Recent antibiotic exposure - avoid fluoroquinolones if used in last 6 months 1
4. Patient factors - male gender (consider 14-day course to cover possible prostatitis), pregnancy (avoid fluoroquinolones), allergies 1

Agents to AVOID in Febrile UTI

Do not use the following for pyelonephritis: 1

• Nitrofurantoin - insufficient data for efficacy in upper tract infections 1
• Oral fosfomycin - inadequate evidence for pyelonephritis 1
• Pivmecillinam - insufficient data for upper tract disease 1

These agents do not achieve adequate blood/tissue concentrations for parenchymal infections and should be reserved only for uncomplicated lower UTI (cystitis). 1

Treatment Duration and Monitoring

• Standard duration: 7-14 days total (no single optimal duration identified, but minimum 7 days required) 1
• Switch to oral therapy once patient is afebrile for 24-48 hours and clinically improving 1
• Obtain repeat imaging if patient remains febrile after 72 hours or clinical deterioration occurs 1
• Tailor antibiotics based on culture results when available 1

Special Considerations for Complicated UTI

If patient has complicating factors (male gender, obstruction, foreign body, immunosuppression, healthcare-associated infection, recent instrumentation), this becomes a complicated UTI requiring: 1

• Broader empirical coverage: Consider aminoglycoside plus second-generation cephalosporin, or third-generation cephalosporin 1
• Longer treatment duration: 14 days for men (to exclude prostatitis) 1
• Management of underlying abnormality is mandatory 1
• Reserve carbapenems only for culture-proven multidrug-resistant organisms 1