What are the empirical antibiotic coverage options for Genitourinary (GU) pathogens?

From the Guidelines

Empirical antibiotic coverage for genitourinary (GU) pathogens should prioritize a combination of amoxicillin plus an aminoglycoside, a second-generation cephalosporin plus an aminoglycoside, or an intravenous third-generation cephalosporin as empirical treatment for complicated UTI with systemic symptoms, as recommended by the European Association of Urology guidelines 1. When selecting empirical antibiotic coverage, it is crucial to consider the local resistance patterns and the severity of the infection. For complicated urinary tract infections (UTIs), the European Association of Urology guidelines suggest using a combination of antibiotics, such as amoxicillin plus an aminoglycoside or a second-generation cephalosporin plus an aminoglycoside, or an intravenous third-generation cephalosporin 1. Key considerations for empirical antibiotic coverage include:

• Using ciprofloxacin only if the local resistance rate is <10% and the patient does not require hospitalization 1
• Avoiding the use of ciprofloxacin and other fluoroquinolones for empirical treatment of complicated UTI in patients from urology departments or when patients have used fluoroquinolones in the last 6 months 1
• Managing any urological abnormality and/or underlying complicating factors 1 In addition to these guidelines, it is essential to consider the specific pathogens involved in GU infections, such as gonococcal and non-gonococcal infections, and to use antimicrobial therapy regimens accordingly, as outlined in the European Association of Urology guidelines 1. Some key points to consider when selecting empirical antibiotic coverage for GU pathogens include:
• The use of ceftriaxone, azithromycin, and doxycycline for the treatment of gonococcal and non-gonococcal infections 1
• The importance of local antibiotic resistance patterns in guiding therapy
• The need to obtain urine cultures before starting antibiotics when possible to allow for targeted therapy once results are available
• The consideration of risk factors for resistant organisms, such as recent hospitalization or antibiotic use, when selecting empirical antibiotic coverage.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION - ADULTS Ciprofloxacin Tablets USP 250 mg, 500 mg and 750 mg should be administered orally to adults as described in the Dosage Guidelines table The determination of dosage for any particular patient must take into consideration the severity and nature of the infection, the susceptibility of the causative organism, the integrity of the patient’s host-defense mechanisms, and the status of renal function and hepatic function.

ADULT DOSAGE GUIDELINES Infection Severity Dose Frequency Usual Durations Uncomplicated Urinary Tract Infections Mild/Moderate 250 mg q 12 h 3 Days Mild to Moderate Uncomplicated or Complicated Urinary Tract Infections, including pyelonephritis, due to E. coli, K. pneumoniae, or P. mirabilis 0.5 to 1 g IV/IM Every 12 hours 7 to 10

The empirical antibiotic coverage for GU pathogens includes:

• Ciprofloxacin: 250 mg every 12 hours for 3 days for uncomplicated urinary tract infections
• Cefepime: 0.5 to 1 g IV/IM every 12 hours for 7 to 10 days for mild to moderate uncomplicated or complicated urinary tract infections, including pyelonephritis, due to E. coli, K. pneumoniae, or P. mirabilis 2
• Ampicillin: used to treat infections caused by susceptible strains of designated organisms, including E. coli, P. mirabilis, enterococci, Shigella, S. typhosa and other Salmonella and nonpenicillinase-producing N. gonorrhoeae 3

From the Research

Empirical Antibiotic Coverage for GU Pathogens

• The choice of empirical antibiotic coverage for genitourinary (GU) pathogens depends on various factors, including the severity of the infection, patient's risk factors, and local epidemiology 4.
• A study published in 2019 found that physicians' perceived likelihood of antibiotic coverage and minimum thresholds of coverage for GU infections were 91% and 90%, respectively, for severe cases, and 90% and 80%, respectively, for mild cases 4.
• Another study published in 2021 found that the most commonly prescribed antibiotic agents for uncomplicated urinary tract infections in women were fluoroquinolones (36.4%), nitrofurantoin (31.8%), and trimethoprim-sulfamethoxazole (26.3%) 5.
• The use of fluoroquinolones has been discouraged due to antibiotic resistance and adverse events, and guidelines recommend nitrofurantoin, trimethoprim-sulfamethoxazole, and Fosfomycin as first-line treatments 5.
• Studies have also evaluated the effectiveness of various antibiotics against Pseudomonas aeruginosa, a common GU pathogen, and found that combination therapy with a beta-lactam and an aminoglycoside or a fluoroquinolone can be effective 6, 7.
• Novel antibiotics, such as cefiderocol, and bacteriophage therapy may also have a promising role in the treatment of P. aeruginosa infections 7.