What is the recommended cefepime (Cefepime) dosing for a patient with Enterobacter cloacae urinary tract infection (UTI) requiring stent and stone removal, with normal renal function (creatinine clearance 89 mL/min)?

Cefepime Dosing for E. cloacae UTI with Stone Removal

For a patient with Enterobacter cloacae UTI requiring stent and stone removal with a creatinine clearance of 89 mL/min, administer cefepime 2 g IV every 12 hours.

Rationale for Dosing

Standard Dosing for Complicated UTI

• Cefepime 2 g IV every 12 hours is the FDA-approved dose for severe complicated UTIs with normal renal function (CrCl >60 mL/min), including pyelonephritis caused by organisms like E. cloacae 1
• Your patient's CrCl of 89 mL/min falls well within the normal renal function range, requiring no dose adjustment 1
• The recommended treatment duration is 7-10 days for complicated UTIs 1

Why This Dose is Critical for E. cloacae

• E. cloacae is an ESBL-risk organism that requires adequate beta-lactam coverage 2
• Cefepime 2 g every 12 hours achieves optimal pharmacodynamic parameters (time above MIC >70%) for Enterobacter species across the full range of normal renal function 3
• This dosing maintains therapeutic concentrations throughout the dosing interval, which is essential for organisms like E. cloacae that may have MICs at the upper limits of susceptibility 4

Procedural Antimicrobial Considerations

Perioperative Coverage for Stone Manipulation

• Antimicrobial prophylaxis is mandatory for any stone manipulation procedure, as this carries increased risk of bacteremia 2
• Since you already have documented E. cloacae UTI, this is treatment rather than prophylaxis—continue the cefepime through the procedure 2
• Administer cefepime within 60 minutes before the procedure and redose intraoperatively if the case exceeds 4 hours 2

Critical Intraoperative Management

• If purulent urine is encountered during the procedure, abort stone removal immediately, establish drainage (ureteral stent or nephrostomy tube), obtain urine culture, and continue broad-spectrum antibiotics 2
• The presence of purulence mandates aborting the procedure even if you've already begun stone manipulation 2

Administration Details

Infusion Parameters

• Administer each 2 g dose as an IV infusion over approximately 30 minutes 1
• For organisms with higher MICs (≥8 mg/L), consider prolonged infusion (over 3 hours) to optimize time above MIC, though this is typically reserved for critically ill patients 2

Monitoring Requirements

• Monitor for neurological symptoms (confusion, muscle jerks, altered mental status) even with normal renal function, as cefepime can cause neurotoxicity 4
• If any neurological symptoms develop, check cefepime trough levels and consider dose reduction or alternative therapy 4
• Obtain repeat urine culture 48-72 hours after starting therapy to confirm susceptibility and clinical response 2

Alternative Considerations

If E. cloacae Shows Resistance

• If susceptibility testing reveals cefepime resistance or ESBL production, switch to a carbapenem (meropenem 1 g IV every 8 hours or imipenem 1 g IV every 8 hours) for complicated UTI with instrumentation 2
• For confirmed carbapenem-resistant Enterobacteriaceae (CRE), newer agents like ceftazidime-avibactam 2.5 g IV every 8 hours are recommended 2

Renal Function Monitoring

• Reassess renal function during therapy, particularly if the patient develops acute kidney injury from obstruction or sepsis 1
• If CrCl drops to 30-60 mL/min during treatment, reduce dose to 2 g IV every 24 hours 1
• If CrCl falls below 30 mL/min, reduce to 1 g IV every 24 hours 1

Duration of Therapy

• Complete a full 10-day course for this complicated UTI with instrumentation 1
• The 10-day duration (rather than 7 days) is appropriate given the need for stone manipulation and the presence of E. cloacae, which can be more difficult to eradicate 2
• If bacteremia is documented, extend therapy based on clearance of blood cultures and clinical response 2