Cefepime Dosing for Peritonitis in Peritoneal Dialysis Patients
For peritonitis in peritoneal dialysis patients, intraperitoneal cefepime should be administered at a dose of 1 gram once daily for 10 days. 1
Dosing Rationale and Evidence
The FDA-approved dosing for cefepime in patients on continuous ambulatory peritoneal dialysis (CAPD) is 2 grams every 48 hours for systemic infections 2. However, for peritonitis specifically in peritoneal dialysis patients, direct intraperitoneal administration has been studied and shown to be effective.
Intraperitoneal Administration
- A randomized controlled trial demonstrated that intraperitoneal cefepime at 1 gram once daily for 10 days achieved primary response rates of 82% and cure rates of 72% in peritoneal dialysis-associated peritonitis 1
- This dosing regimen was found to be equally effective compared to the combination of vancomycin and netilmicin, with fewer side effects and lower cost 1
Pharmacokinetic Considerations
- Cefepime has favorable stability in peritoneal dialysis solutions, retaining >90% of its concentration for up to 96 hours at room temperature (25°C) 3
- When administered intraperitoneally, cefepime achieves adequate concentrations in both the peritoneal fluid and serum to treat common pathogens causing peritonitis 4
Treatment Duration and Monitoring
The recommended duration of therapy for peritoneal dialysis-associated peritonitis is 10 days 1. This aligns with general guidelines for complicated intra-abdominal infections, which recommend 7-10 days of antimicrobial therapy 5.
Important Monitoring Parameters:
- Clinical response (fever resolution, decreased abdominal pain, clearing of dialysate)
- Dialysate cell count (should show decreasing white blood cell count)
- Follow-up cultures (should become negative)
Special Considerations
Residual Renal Function
- Peritonitis may negatively impact residual kidney function in peritoneal dialysis patients 5
- Reassessing residual kidney function after resolution of peritonitis is recommended 5
Peritoneal Clearance Measurements
- All measurements of peritoneal solute clearance should be delayed until at least 1 month after resolution of peritonitis 5
- Peritonitis transiently changes the patient to a high transporter status and decreases ultrafiltration 5
Alternative Regimens
- For patients with severe reactions to β-lactam antibiotics, ciprofloxacin plus metronidazole or an aminoglycoside-based regimen can be considered 5
- For suspected or confirmed Pseudomonas peritonitis, higher doses or combination therapy may be warranted
Pitfalls and Caveats
Secondary Peritonitis: Be vigilant for signs of secondary peritonitis (perforation or abscess), which would require surgical intervention in addition to antibiotics. Signs include multiple organisms on culture, high protein, high LDH, or low glucose in peritoneal fluid 5
Follow-up Paracentesis: While not needed in all cases, repeat peritoneal fluid analysis should be performed if clinical response is inadequate or atypical features are present 5
Drug Stability: When preparing cefepime for intraperitoneal administration, note that it remains stable for up to 96 hours at room temperature in pH-neutral peritoneal dialysis solutions 3
Timing of Administration: For patients on hemodialysis in addition to peritoneal dialysis, cefepime should be administered after hemodialysis to prevent premature drug removal 6
By following these recommendations, peritoneal dialysis-associated peritonitis can be effectively treated while minimizing the risk of complications and preserving residual renal function.