What is the management of acute pyelonephritis?

From the Guidelines

Management of acute pyelonephritis requires prompt antibiotic therapy and supportive care, with oral fluoroquinolones like ciprofloxacin (500mg twice daily for 7 days) or levofloxacin (750mg once daily for 5-7 days) being first-line treatments for uncomplicated cases in otherwise healthy patients, as recommended by the European Association of Urology guidelines 1. For uncomplicated cases, the choice of antibiotic should be based on local resistance patterns and the severity of illness at presentation.

• Oral fluoroquinolones are preferred for empirical therapy in areas with low fluoroquinolone resistance rates (<10%) 1.
• Trimethoprim-sulfamethoxazole (160/800mg twice daily for 14 days) can be used if the pathogen is susceptible, but its use is limited due to high rates of resistance 1.
• Patients with severe symptoms, immunocompromise, pregnancy, or inability to tolerate oral medications should be hospitalized for intravenous antibiotics such as ceftriaxone (1-2g daily), ampicillin plus gentamicin, or piperacillin-tazobactam until clinical improvement, then transition to oral therapy to complete 7-14 days total 1. Adequate hydration is essential, along with antipyretics and pain management as needed.
• Urine culture should be obtained before starting antibiotics to guide therapy 1.
• Follow-up urine cultures are recommended 1-2 weeks after completing treatment to ensure resolution 1. Patients should be advised to increase fluid intake, urinate frequently, and complete the full antibiotic course even if symptoms improve. Pyelonephritis is typically caused by ascending urinary tract infections with uropathogenic bacteria, most commonly E. coli, which can lead to kidney inflammation and potential complications if not properly treated 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).

Management of Acute Pyelonephritis:

• Levofloxacin is indicated for the treatment of acute pyelonephritis caused by Escherichia coli, including cases with concurrent bacteremia.
• The recommended treatment regimen is 5 or 10 days of levofloxacin tablets.
• A clinical trial compared levofloxacin 750 mg once daily for 5 days with ciprofloxacin 400 mg twice daily for 10 days, and the results showed that levofloxacin was effective in treating acute pyelonephritis 2 2.
• Key points to consider in the management of acute pyelonephritis include:
  • Pathogen identification: Identifying the causative pathogen, such as Escherichia coli, is crucial for effective treatment.
  • Treatment duration: The treatment duration for acute pyelonephritis is typically 5 or 10 days.
  • Antibiotic choice: Levofloxacin is a recommended antibiotic for the treatment of acute pyelonephritis caused by Escherichia coli.

From the Research

Diagnosis and Classification

• Acute pyelonephritis should be suspected in patients with flank pain and laboratory evidence of urinary tract infection 3
• The diagnostic workup includes history, physical examination, urinalysis (including a Gram stain), and urine culture 4
• Patients with suspected complicated pyelonephritis require the standard assessment plus blood cultures and urinary tract imaging, preferably a computed tomography (CT) scan 4
• Acute pyelonephritis can be classified clinically at the time of presentation into either uncomplicated or complicated categories 4

Treatment Options

• Outpatient oral antibiotic therapy with a fluoroquinolone is successful in most patients with mild uncomplicated pyelonephritis 5
• Other effective alternatives include extended-spectrum penicillins, amoxicillin-clavulanate potassium, cephalosporins, and trimethoprim-sulfamethoxazole 5
• Indications for inpatient treatment include complicated infections, sepsis, persistent vomiting, failed outpatient treatment, or extremes of age 5
• In hospitalized patients, intravenous treatment is recommended with a fluoroquinolone, aminoglycoside with or without ampicillin, or a third-generation cephalosporin 5
• Ceftriaxone was more effective than levofloxacin in the treatment of acute pyelonephritis, based on microbiological response 6

Antibiotic Resistance and Duration of Therapy

• High resistance rates were detected for cotrimoxazole, ciprofloxacin, and ceftriaxone in isolated E.coli 6
• The standard duration of therapy is seven to 14 days 5
• Choosing the treatment regimen based on susceptibility testing results and shortening the duration of the therapy are recommended to decrease the spread of antibiotic resistance worldwide 6
• Urine culture should be repeated one to two weeks after completion of antibiotic therapy to ensure eradication of the infection 5

Special Considerations

• Pregnant patients with pyelonephritis are at significantly elevated risk of severe complications and should be admitted and treated initially with parenteral therapy 3
• Patients with concurrent urinary tract obstruction should be referred for urgent decompression 3
• Patients who do not respond to treatment within 48 to 72 hours should be evaluated with imaging and repeat cultures while alternative diagnoses are considered 3