What antibiotic is recommended for the treatment of pyelonephritis?

Antibiotic Treatment for Pyelonephritis

Oral ciprofloxacin 500 mg twice daily for 7 days is the first-line treatment for pyelonephritis in areas where fluoroquinolone resistance is below 10%. 1

Initial Assessment and Antibiotic Selection

• Always obtain urine culture and susceptibility testing before initiating therapy to guide definitive treatment 1
• Initial empiric therapy should be based on local resistance patterns and adjusted according to culture results 1
• In areas with fluoroquinolone resistance >10%, administer an initial one-time intravenous dose of ceftriaxone 1g or an aminoglycoside before starting oral therapy 1, 2

Outpatient Treatment Options

• First-line oral options:
  • Ciprofloxacin 500 mg twice daily for 7 days 1, 3
  • Ciprofloxacin 1000 mg extended-release once daily for 7 days 1
  • Levofloxacin 750 mg once daily for 5 days 1, 4
• Alternative if pathogen is known to be susceptible:
  • Trimethoprim-Sulfamethoxazole (TMP-SMX) 160/800 mg twice daily for 14 days 1
• Oral β-lactams are less effective than other available agents but can be used if the pathogen is susceptible 1

Inpatient Treatment Options

• For hospitalized patients, recommended IV regimens include:
  • Fluoroquinolone (e.g., levofloxacin 750 mg daily) 1, 4
  • Aminoglycoside with or without ampicillin 1
  • Extended-spectrum cephalosporin (e.g., ceftriaxone 1g every 12 hours) 1, 5
  • Extended-spectrum penicillin with or without aminoglycoside 1
  • Carbapenem 1

Treatment Duration

• Fluoroquinolones: 5-7 days 1, 3
• TMP-SMX: 14 days 1
• β-lactams: 10-14 days 1

Special Considerations

• Escherichia coli is the most common pathogen (75-95%) in pyelonephritis 1, 2
• Increasing resistance to fluoroquinolones has been reported in many regions, necessitating careful selection of empiric therapy 5, 6
• For Pseudomonas aeruginosa infections, combination therapy with an anti-pseudomonal β-lactam is recommended 4
• Monitor elderly patients closely for adverse effects, particularly with aminoglycosides and fluoroquinolones 1

Common Pitfalls to Avoid

• Failing to obtain urine cultures before starting antibiotics 1
• Not considering local resistance patterns when selecting empiric therapy 1, 6
• Using fluoroquinolones empirically in areas with >10% resistance without an initial parenteral dose 1
• Using oral β-lactams as monotherapy without an initial parenteral dose 1
• Not adjusting therapy based on culture results 1
• Inadequate treatment duration, especially with β-lactam agents 1

Step-Down Therapy

• Once clinical improvement occurs in hospitalized patients, transition to appropriate oral therapy based on culture results 1, 7
• Complete the full course of antibiotics even after symptom resolution 1