What are the recommended antibiotics for the treatment of Pyelonephritis (infection of the kidney)?

From the Guidelines

For uncomplicated pyelonephritis, oral fluoroquinolones like ciprofloxacin (500mg twice daily for 7 days) or levofloxacin (750mg once daily for 5 days) are first-line treatments, as recommended by the European Association of Urology guidelines 1. When considering treatment options for pyelonephritis, it's essential to prioritize the most recent and highest quality evidence to minimize morbidity, mortality, and improve quality of life.

• The European Association of Urology guidelines 1 suggest that fluoroquinolone resistance should be less than 10% for empirical treatment.
• If local resistance rates to fluoroquinolones exceed 10%, consider alternative treatments like trimethoprim-sulfamethoxazole (160/800mg twice daily for 14 days) or an oral beta-lactam like amoxicillin-clavulanate (875/125mg twice daily for 14 days) 1.
• For hospitalized patients with complicated pyelonephritis, intravenous options include ceftriaxone (1-2g daily), gentamicin (5-7mg/kg daily), or piperacillin-tazobactam (3.375g every 6 hours) 1.
• Treatment should be guided by urine culture results when available, and patients should complete the full antibiotic course even if symptoms improve quickly, drink plenty of fluids, and take analgesics for pain relief.
• The American College of Physicians also recommends short-course therapy with fluoroquinolones (5 to 7 days) or TMP–SMZ (14 days) for uncomplicated pyelonephritis, based on antibiotic susceptibility 1.

From the FDA Drug Label

1. 11 Acute Pyelonephritis: 5 or 10 Day Treatment Regimen Levofloxacin tablets are indicated for the treatment of acute pyelonephritis caused by Escherichia coli, including cases with concurrent bacteremia [see Clinical Studies (14.7,14.8)].
2. 7 Complicated Urinary Tract Infections and Acute Pyelonephritis: 5 Day Treatment Regimen To evaluate the safety and efficacy of the higher dose and shorter course of levofloxacin, 1109 patients with cUTI and AP were enrolled in a randomized, double-blind, multicenter clinical trial conducted in the U.S. from November 2004 to April 2006 comparing levofloxacin 750 mg I. V. or orally once daily for 5 days (546 patients) with ciprofloxacin 400 mg I. V. or 500 mg orally twice daily for 10 days (563 patients).

Levofloxacin is indicated for the treatment of acute pyelonephritis caused by Escherichia coli. The recommended treatment regimen is 5 or 10 days.

• The 5-day treatment regimen has been evaluated in a clinical trial comparing levofloxacin 750 mg once daily with ciprofloxacin 400 mg twice daily for 10 days 2.
• The 10-day treatment regimen has also been evaluated in a clinical trial comparing levofloxacin 250 mg once daily with ciprofloxacin 500 mg twice daily for 10 days 2.

From the Research

Pyelonephritis Antibiotics

• The most common pathogen in acute pyelonephritis is Escherichia coli, and there has been an increasing rate of E. coli resistance to extended-spectrum beta-lactam antibiotics 3.
• Practice guidelines recommend oral fluoroquinolones as initial outpatient therapy if the rate of fluoroquinolone resistance in the community is 10 percent or less. If the resistance rate exceeds 10 percent, an initial intravenous dose of ceftriaxone or gentamicin should be given, followed by an oral fluoroquinolone regimen 3.
• A study compared the efficacy and safety of levofloxacin 750 mg once daily for 5 days to ciprofloxacin twice daily for 10 days for the treatment of complicated urinary tract infections and acute pyelonephritis, and found that both drug regimens are safe and effective, and that a 5-day course of therapy with levofloxacin is noninferior to a 10-day course of therapy with ciprofloxacin 4, 5.
• Another study found that there was no significant difference in UTI recurrence rates between oral cephalosporins and first-line agents in the treatment of acute pyelonephritis in the outpatient setting 6.
• A retrospective chart review found that failure of therapy for pyelonephritis occurred more often in the fluoroquinolone and trimethoprim-sulfamethoxazole group than in the cephalosporin group, and that trimethoprim-sulfamethoxazole showed statistical significance for more bacterial resistance compared to the other agents 7.

Treatment Options

• Oral fluoroquinolones, such as ciprofloxacin and levofloxacin, are commonly used to treat pyelonephritis 3, 4, 5.
• Cephalosporins, such as ceftriaxone and cephalexin, may be used as an alternative to fluoroquinolones, especially in areas with high resistance rates 3, 6, 7.
• Trimethoprim-sulfamethoxazole may be used to treat pyelonephritis, but it is not recommended as a first-line agent due to high resistance rates 3, 7.
• Aminoglycosides, such as gentamicin, may be used to treat pyelonephritis, especially in severe cases or in patients with complicated infections 3.