When is cefepime appropriate for treating a urinary tract infection and what is the recommended dosing, including renal‑function adjustments?

Cefepime for Urinary Tract Infections

When to Use Cefepime

Cefepime is appropriate for hospitalized patients with uncomplicated or complicated pyelonephritis requiring parenteral therapy, and should be reserved for severe UTIs rather than simple cystitis. 1

Clinical Indications

For uncomplicated pyelonephritis requiring hospitalization:

• Cefepime is recommended as part of initial intravenous empiric therapy alongside fluoroquinolones, aminoglycosides, or other extended-spectrum cephalosporins 1
• Use when oral therapy is not feasible or the patient requires inpatient management 1
• Reserve carbapenems and novel broad-spectrum agents only for patients with early culture results showing multidrug-resistant organisms 1

For complicated UTIs (cUTIs):

• Appropriate for patients with host-related factors or anatomic/functional urinary tract abnormalities 1
• Effective for infections caused by susceptible Enterobacteriaceae, including some resistant strains 1
• Clinical studies demonstrate 89-92% cure rates in complicated UTI 2

For severe UTIs with specific pathogens:

• Effective against E. coli, K. pneumoniae, and P. mirabilis 3
• Maintains activity against some organisms resistant to third-generation cephalosporins 4

Dosing Recommendations

Standard Adult Dosing

For mild to moderate uncomplicated or complicated UTI (including pyelonephritis):

• 0.5-1 g IV every 12 hours for 7-10 days 3

For severe uncomplicated or complicated UTI:

• 2 g IV every 12 hours for 10 days 3

Administration:

• Infuse intravenously over approximately 30 minutes 3
• The twice-daily dosing schedule offers convenience compared to three-times-daily regimens 4, 5

Pediatric Dosing (2 months to 16 years)

For uncomplicated and complicated UTI (including pyelonephritis):

• 50 mg/kg per dose every 12 hours (maximum dose should not exceed adult dose) 3

Renal Function Adjustments

Dose adjustment is mandatory for creatinine clearance ≤60 mL/min to compensate for slower renal elimination 3

Dosing by Creatinine Clearance

For standard 2g every 12 hours regimen (severe UTI):

• CrCl 30-60 mL/min: 2 g every 24 hours 3
• CrCl 11-29 mL/min: 1 g every 24 hours 3
• CrCl <11 mL/min: 500 mg every 24 hours 3

For standard 1g every 12 hours regimen (moderate UTI):

• CrCl 30-60 mL/min: 1 g every 24 hours 3
• CrCl 11-29 mL/min: 500 mg every 24 hours 3
• CrCl <11 mL/min: 250 mg every 24 hours 3

For hemodialysis patients:

• 1 g on Day 1, then 500 mg every 24 hours thereafter (for most infections) 3
• Administer after hemodialysis on dialysis days, as approximately 68% of cefepime is removed during a 3-hour dialysis session 3

For continuous ambulatory peritoneal dialysis (CAPD):

• Administer at 48-hour intervals (double the standard dosing interval) 3

Important Clinical Considerations

Antimicrobial Stewardship Context

Cefepime should not be first-line for uncomplicated UTI or simple cystitis:

• First-line oral options include nitrofurantoin, trimethoprim-sulfamethoxazole (if local resistance <20%), or amoxicillin-clavulanate 6
• β-lactams like cephalosporins are second-line agents with inferior efficacy for uncomplicated UTIs 6
• They may promote more rapid UTI recurrence and cause greater collateral damage to fecal microbiota 6

Resistance Considerations

Cefepime offers advantages over third-generation cephalosporins:

• Lower propensity for inducing bacterial resistance 4
• Retains activity against some Enterobacter and E. coli strains resistant to other cephalosporins 4
• Active against selected P. aeruginosa strains resistant to ceftazidime 4

Safety Profile

Cefepime is generally well-tolerated:

• Most common adverse events include headache, diarrhea, and vomiting 2
• Local intolerance at infusion site occurs in approximately 9% of patients 7
• Discontinuation due to adverse events is rare (2-3%) 2, 5
• Laboratory abnormalities are typically clinically insignificant 2

Common Pitfalls to Avoid

Do not use cefepime as empiric monotherapy without considering:

• Local resistance patterns should guide empiric selection 1
• Gram-positive coverage may be inadequate for polymicrobial infections 1
• For complicated intra-abdominal infections with UTI component, combine with metronidazole 3

Do not forget renal dose adjustments:

• Failure to adjust for renal impairment increases toxicity risk 3
• Always calculate creatinine clearance using the Cockcroft-Gault equation when serum creatinine is available 3