From the Guidelines
The recommended treatment for pyelonephritis typically involves antibiotics, with the specific regimen depending on severity and patient factors, and according to the most recent guidelines from the European Association of Urology in 2024 1, fluoroquinolones and cephalosporins are the only antimicrobial agents that can be recommended for oral empiric treatment of uncomplicated pyelonephritis. For uncomplicated cases, oral fluoroquinolones like ciprofloxacin (500mg twice daily for 7 days) or levofloxacin (750mg once daily for 5-7 days) are commonly prescribed, as suggested by the guidelines 1. Alternatively, trimethoprim-sulfamethoxazole (160/800mg twice daily for 14 days) may be used if the pathogen is susceptible, but its use is limited due to high rates of resistance and corresponding failure rates 1. For more severe cases requiring hospitalization, initial intravenous antibiotics such as ceftriaxone (1-2g daily), ampicillin plus gentamicin, or a fluoroquinolone are recommended until clinical improvement, followed by oral therapy to complete 7-14 days of treatment, as recommended by the guidelines 1. Patients should increase fluid intake to promote urinary flow and may take acetaminophen or NSAIDs for fever and pain relief. Treatment should begin promptly as pyelonephritis involves bacterial infection of the kidney tissue that can lead to permanent damage or sepsis if untreated. Antibiotic selection may need adjustment based on local resistance patterns and urine culture results, which should be obtained before starting antibiotics whenever possible, as emphasized by the guidelines 1.
Some key points to consider in the treatment of pyelonephritis include:
- The use of fluoroquinolones and cephalosporins as first-line treatment for uncomplicated pyelonephritis 1
- The importance of adjusting antibiotic selection based on local resistance patterns and urine culture results 1
- The need for prompt treatment to prevent permanent damage or sepsis 1
- The use of trimethoprim-sulfamethoxazole as an alternative treatment option, but with caution due to high rates of resistance 1
- The recommendation for hospitalization and initial intravenous antibiotics for more severe cases of pyelonephritis 1
From the FDA Drug Label
Complicated Urinary Tract Infections (cUTI), Including Pyelonephritis, in adult and pediatric patients (birth to less than 18 years old). Recommended Dosage of ZERBAXA by Infection in Adult Patients (18 years or older) with Creatinine Clearance (CrCl) Greater than 50 mL/min Infection Dose Duration of Treatment Complicated Urinary Tract Infections (cUTI), Including Pyelonephritis 1.5 g 7 days
The recommended treatment for pyelonephritis is ceftolozane-tazobactam (IV) at a dose of 1.5 g every 8 hours for 7 days in adult patients with creatinine clearance (CrCl) greater than 50 mL/min 2.
- Key points:
- The treatment is for complicated urinary tract infections, including pyelonephritis.
- The dose is 1.5 g every 8 hours.
- The duration of treatment is 7 days.
- The recommendation is for adult patients with CrCl greater than 50 mL/min.
- Alternative option:
- Levofloxacin (PO) is also indicated for the treatment of acute pyelonephritis caused by Escherichia coli, including cases with concurrent bacteremia 3.
From the Research
Treatment Options for Pyelonephritis
The recommended treatment for pyelonephritis typically involves antibiotics, with the choice of antibiotic depending on various factors such as the severity of the infection, the causative organism, and local resistance patterns.
- Fluoroquinolones: Studies have shown that fluoroquinolones, such as ciprofloxacin and levofloxacin, are effective in treating pyelonephritis 4, 5. A 7-day course of ciprofloxacin has been found to be non-inferior to a 14-day course in women with acute pyelonephritis 4.
- Cephalosporins: Injectable third-generation cephalosporins, such as ceftriaxone, are also effective against enterobacteria, including E. coli, and have good kidney penetration 6, 7. However, the prevalence of E. coli resistance to third-generation cephalosporins is rising rapidly in some countries.
- Aminoglycosides: Monotherapy with an aminoglycoside is an alternative that has not been evaluated in this clinical situation, but due to the serious irreversible adverse effects of aminoglycosides, they should only be used when the other options are unacceptable 8, 7.
Considerations for Treatment
When choosing an antibiotic for pyelonephritis, it is essential to consider the local resistance patterns and the patient's medical history, including any recent antibiotic use or hospitalization.
- Resistance Patterns: The prevalence of resistance to fluoroquinolones and cephalosporins is rising in some countries, making it crucial to adjust the empirical treatment based on antimicrobial susceptibility testing results 6, 7.
- Antibiotic Stewardship: To preserve the efficacy of broader-spectrum antibiotics, they should not be used as empirical therapy for non-serious infections, and fluoroquinolones and third-generation cephalosporins should be avoided whenever possible in non-serious infections 7.