What is the recommended treatment for pyelonephritis?

Treatment of Pyelonephritis

Fluoroquinolones for 5-7 days are the first-line therapy for uncomplicated pyelonephritis in adults, with clinical cure rates exceeding 93%. 1

Initial Assessment and Diagnosis

• Obtain urine culture before starting antibiotics to guide therapy
• Clinical presentation typically includes:
  • Fever (may be absent early in illness)
  • Flank pain (nearly universal)
  • Urinary symptoms (frequency, urgency, dysuria)
• Positive urinalysis confirms diagnosis in patients with compatible symptoms
• E. coli is the most common pathogen in acute pyelonephritis

Antibiotic Selection

Outpatient Treatment (Uncomplicated Cases)

1. First-line therapy:

   • Fluoroquinolones for 5-7 days 1
     • Ciprofloxacin 500mg twice daily OR
     • Levofloxacin 750mg once daily
   • Only recommended when local resistance rates are <10% 1

2. Alternative options (if fluoroquinolones contraindicated or resistance >10%):

   • Cefpodoxime for 10-14 days
   • Trimethoprim-sulfamethoxazole for 14 days
   • β-lactams for 10-14 days 1

Inpatient Treatment (Complicated Cases)

Indications for hospitalization:

• Complicated infections
• Sepsis
• Persistent vomiting
• Failed outpatient treatment
• Extremes of age 2

Recommended IV regimens:

• Fluoroquinolone
• Aminoglycoside with or without ampicillin
• Third-generation cephalosporin 2

Special Populations

Pregnant Patients

• Require admission for initial parenteral therapy
• Fluoroquinolones are contraindicated due to teratogenic effects 1

Patients with Renal Impairment

• Patients with CrCl ≥50 mL/min: no dosage adjustment needed
• Patients with CrCl <30 mL/min: require dosage adjustment 1
• Closer monitoring recommended due to increased risk of recurrence 1

Treatment Duration

For acute pyelonephritis, the FDA-approved regimens include:

• Levofloxacin 750mg once daily for 5 days 3
• Levofloxacin 250mg once daily for 10 days 3

Research supports shorter treatment courses:

• A randomized controlled trial demonstrated that 7-day ciprofloxacin treatment was non-inferior to 14-day treatment, with clinical cure rates of 97% and 96%, respectively 4

Monitoring and Follow-up

• Clinical improvement should be expected within 48-72 hours of starting treatment 1
• If no improvement after 3-5 days, reassess with repeat cultures 1
• Consider follow-up urine culture 1-2 weeks after completion of therapy, particularly in patients with recurrent UTIs 2
• Monitor CBC and CMP at the end of therapy to assess for adverse effects and treatment response 1

Common Pitfalls and Caveats

1. Fluoroquinolone resistance: Only use as empiric therapy when local resistance rates are <10% 1

2. Treatment failure: May be caused by:

   • Resistant organisms
   • Underlying anatomic/functional abnormalities
   • Immunosuppressed states 2
   • Consider imaging (CT) if symptoms persist or recur after initial improvement 5

3. Adverse effects: Monitor for:

   • Gastrointestinal effects
   • Central nervous system effects
   • Skin sensitivity to sunlight 1
   • Advise patients to avoid excessive sun exposure and use sunscreen 1

4. Drug interactions: Advise patients to report all medications they are taking, including over-the-counter drugs 1