What is the appropriate management for a patient with a urinary tract infection (UTI) presenting with fever, leukocytosis, and a high granulocyte percentage?

Management of Febrile Urinary Tract Infection

For a patient presenting with fever (38°C), leukocytosis (WBC 15.3 × 10^9/L), elevated granulocytes (83%), and UTI, immediate broad-spectrum antibiotic therapy with a fluoroquinolone or trimethoprim-sulfamethoxazole is recommended based on local resistance patterns.

Initial Assessment and Treatment

• The combination of fever, leukocytosis, and elevated granulocyte percentage indicates a systemic inflammatory response consistent with complicated UTI or urosepsis 1, 2
• Immediate empiric antimicrobial therapy should be initiated without delay to reduce morbidity and mortality 1
• Obtain urine culture before starting antibiotics if possible, but do not delay treatment 1

Antibiotic Selection

First-line options:

• Trimethoprim-sulfamethoxazole (TMP-SMX): 160/800 mg twice daily for 7-14 days if local resistance patterns are favorable (<20%) 3, 4
• Fluoroquinolones (e.g., ciprofloxacin 500 mg twice daily for 7-10 days) are effective for complicated UTIs but should be used judiciously due to resistance concerns 5, 6

Alternative options:

• Fourth-generation cephalosporins if Extended-Spectrum Beta-Lactamase (ESBL) is absent 1
• Carbapenems (meropenem, imipenem) for suspected multidrug-resistant infections 1
• For ESBL-producing organisms, consider pivmecillinam with amoxicillin/clavulanic acid as step-down therapy after initial IV treatment 7

Treatment Duration and Monitoring

• For complicated UTI with systemic symptoms, a 7-14 day course is recommended 1, 4
• Monitor clinical response within 48-72 hours 1
• If fever persists despite appropriate antibiotics:
  • Evaluate for urinary obstruction, abscess, or other complications 1
  • Consider imaging (ultrasound or CT) to rule out structural abnormalities 1
  • Reassess antibiotic choice based on culture results when available 1

Special Considerations

• If the patient has signs of sepsis (tachycardia, hypotension), consider initial IV antibiotics before transitioning to oral therapy 1
• Antimicrobial regimens should target gram-negative Enterobacteriaceae, which are the most common pathogens in UTIs 1, 4
• Adjust therapy based on culture and susceptibility results when available 1, 4

Supportive Measures

• Ensure adequate hydration 2
• Antipyretics for symptomatic fever management 2
• Monitor for clinical improvement (resolution of fever, normalization of WBC count) 2

Common Pitfalls to Avoid

• Delaying antibiotic therapy in patients with systemic symptoms can increase morbidity and mortality 1
• Using fluoroquinolones as first-line when local resistance rates are high (>10%) 4
• Failing to adjust antibiotics based on culture results 1
• Inadequate treatment duration for complicated UTIs 4
• Not considering structural or functional abnormalities in patients with recurrent or persistent infections 1

Remember that the patient's elevated WBC count with high granulocyte percentage indicates a significant inflammatory response that requires prompt and appropriate antimicrobial therapy to prevent progression to more severe infection and potential sepsis 1, 2.