What are the treatment options for outpatient management of acute pyelonephritis (infection of the kidney)?

From the Guidelines

Outpatient treatment of pyelonephritis should typically involve oral antibiotics for 7-14 days, with fluoroquinolones like ciprofloxacin (500mg twice daily) or levofloxacin (750mg once daily) being first-line options, as recommended by the most recent guidelines 1. The choice of antibiotic should be based on local resistance patterns and the patient's specific situation, with fluoroquinolone resistance being a key consideration 1. Key points to consider in outpatient treatment include:

• The patient should be hemodynamically stable, able to tolerate oral medications, and have no severe comorbidities 1.
• Reliable follow-up is crucial to ensure the patient's condition does not worsen and to adjust the antibiotic regimen if necessary 1.
• Patients should be well-hydrated, take analgesics for pain relief, and complete the full antibiotic course even if symptoms improve 1.
• Urine culture and antimicrobial susceptibility testing should be performed in all cases of pyelonephritis to guide therapy if the patient fails to improve 1.
• Evaluation of the upper urinary tract via ultrasound should be performed to rule out urinary tract obstruction or renal stone disease in patients with a history of urolithiasis, renal function disturbances, or a high urine pH 1.
• Additional investigations, such as a contrast-enhanced computed tomography scan or excretory urography, should be considered if the patient remains febrile after 72 hours of treatment or if there is a deterioration in clinical status 1. It is also important to note that fluoroquinolones and cephalosporins are the only antimicrobial agents that can be recommended for oral empiric treatment of uncomplicated pyelonephritis, with other agents like nitrofurantoin, oral fosfomycin, and pivmecillinam being avoided due to insufficient data regarding their efficacy 1. In cases where the prevalence of fluoroquinolone resistance is thought to exceed 10%, an initial intravenous dose of a long-acting parenteral antimicrobial, such as 1g of ceftriaxone, is recommended 1. Overall, the goal of outpatient treatment of pyelonephritis is to provide effective antibiotic therapy while minimizing the risk of complications and promoting a quick recovery, with the most recent and highest quality evidence guiding clinical decision-making 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).

Outpatient treatment of pyelonephritis can be done with levofloxacin (PO). The recommended treatment regimen is 5 or 10 days. The drug is indicated for the treatment of acute pyelonephritis caused by Escherichia coli, including cases with concurrent bacteremia 2.

• Levofloxacin 750 mg orally once daily for 5 days is a recommended treatment option for acute pyelonephritis 2.
• The bacteriologic cure rates for levofloxacin in the treatment of acute pyelonephritis are presented in Table 20 and Table 21 2.

It is essential to note that the treatment regimen should be determined based on the severity of the infection, the causative pathogen, and the patient's overall health status.

From the Research

Outpatient Treatment of Pyelonephritis

• The outpatient treatment of pyelonephritis is a common practice, with most patients being treated with oral antibiotics 3, 4.
• The choice of antibiotic depends on the severity of the infection, the patient's overall health, and the presence of any underlying medical conditions 3, 4.
• Fluoroquinolones, such as ciprofloxacin, are commonly used for outpatient treatment of pyelonephritis due to their effectiveness against Escherichia coli, the most common cause of the infection 3, 4, 5.
• Other effective alternatives for outpatient treatment include extended-spectrum penicillins, amoxicillin-clavulanate potassium, cephalosporins, and trimethoprim-sulfamethoxazole 3, 4.
• A systematic review of randomized clinical trials found that oral antibiotics, such as cefaclor, ciprofloxacin, and norfloxacin, had comparable clinical success rates for the outpatient treatment of pyelonephritis, ranging from 83% to 95% 6.
• However, the review also noted that there is a need for high-quality clinical trials with more consistent designs and reporting of outcomes to determine the best oral antibiotic treatment for pyelonephritis 6.
• A retrospective chart review found that cephalosporins had a lower failure rate compared to fluoroquinolones and trimethoprim-sulfamethoxazole for the treatment of pyelonephritis in discharged patients from a community hospital setting 7.
• A randomized trial comparing ciprofloxacin (7 days) and trimethoprim-sulfamethoxazole (14 days) for acute uncomplicated pyelonephritis in women found that the ciprofloxacin regimen had greater bacteriologic and clinical cure rates, especially in patients infected with trimethoprim-sulfamethoxazole-resistant strains 5.

Indications for Inpatient Treatment

• Indications for inpatient treatment of pyelonephritis include complicated infections, sepsis, persistent vomiting, failed outpatient treatment, or extremes of age 3, 4.
• In hospitalized patients, intravenous treatment is recommended with a fluoroquinolone, aminoglycoside with or without ampicillin, or a third-generation cephalosporin 3.

Duration of Therapy and Follow-up

• The standard duration of therapy for pyelonephritis is 7 to 14 days 3, 4.
• Urine culture should be repeated one to two weeks after completion of antibiotic therapy to ensure that the infection has been fully cleared 3.
• Treatment failure may be caused by resistant organisms, underlying anatomic/functional abnormalities, or immunosuppressed states, and may require a change in antibiotics or surgical intervention 3.