What is the treatment for pyelonephritis?

Treatment of Pyelonephritis

Fluoroquinolones are the preferred first-line treatment for uncomplicated pyelonephritis in outpatients, with levofloxacin 750 mg once daily for 5 days or ciprofloxacin 500 mg twice daily for 7 days being the most effective options when local resistance rates are below 10%. 1

Initial Assessment and Diagnosis

• Always obtain a urine culture and susceptibility test before starting antibiotics to guide definitive therapy once results are available 2
• Evaluate for signs requiring hospitalization, including high fever, inability to tolerate oral medications, hemodynamic instability, or concern for complications 2
• Consider ultrasound evaluation to rule out urinary tract obstruction or renal stones, particularly in patients with a history of urolithiasis 2

Outpatient Treatment Options

First-Line Therapy

• Oral fluoroquinolones are the preferred first-line treatment for uncomplicated pyelonephritis in outpatients 1:
  • Levofloxacin 750 mg once daily for 5 days 3
  • Ciprofloxacin 500-750 mg twice daily for 7 days 1

Alternative Therapy

• Trimethoprim-sulfamethoxazole (TMP-SMX) 160/800 mg twice daily for 14 days is appropriate only if the uropathogen is known to be susceptible 4, 1
• Oral β-lactams are less effective than fluoroquinolones for pyelonephritis and should be used with caution 1, 2
• If an oral β-lactam must be used, an initial IV dose of a long-acting parenteral antimicrobial (such as ceftriaxone 1g) is strongly recommended 1

Inpatient Treatment Options

• Indications for hospitalization include 5:

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

• Recommended IV antibiotic options include 1, 5:

  • Fluoroquinolones
  • Aminoglycosides (with or without ampicillin)
  • Extended-spectrum cephalosporins
  • Carbapenems (for multidrug-resistant organisms)

Treatment Duration

• Fluoroquinolones: 5-7 days (depending on the specific agent) 1, 2
• TMP-SMX: 14 days 4, 1
• Oral β-lactams: 10-14 days 1

Special Populations

Diabetic Patients

• Patients with diabetes are more vulnerable to complications from acute pyelonephritis, including renal abscesses and emphysematous pyelonephritis 4
• Up to 50% of diabetic patients may not present with typical flank tenderness, making diagnosis more challenging 4

High-Risk Populations

• Additional higher-risk populations include those with 4:
  • Anatomic abnormalities of the urinary tract
  • Vesicoureteral reflux
  • Renal obstruction
  • Pregnancy
  • Nosocomial infection
  • Infections by treatment-resistant pathogens
  • Transplant recipients
  • Immunosuppressed patients

Follow-up and Monitoring

• Patients should show clinical improvement within 48-72 hours of starting appropriate therapy 2
• If the patient remains febrile after 72 hours or shows clinical deterioration, consider imaging studies and possible hospitalization 2
• Urine culture should be repeated 1-2 weeks after completion of antibiotic therapy 5

Common Pitfalls to Avoid

• Using oral β-lactams as monotherapy without an initial parenteral dose can lead to treatment failure due to their inferior efficacy in pyelonephritis 1
• Failing to consider local resistance patterns when selecting empiric therapy can contribute to antimicrobial resistance 1, 2
• Using agents like nitrofurantoin or oral fosfomycin for pyelonephritis is not recommended due to insufficient data regarding efficacy 1
• Delaying appropriate antibiotic therapy, which can lead to complications including renal scarring, hypertension, and end-stage renal disease 4