Definition

Peritoneal dialysis (PD) uses the peritoneum as the dialysis membrane. The concentration of the peritoneal dialysate controls fluid removal.

• Continuous ambulatory PD (CAPD): 4-5 exchanges/day of 1.5-3L per exchange.
• Continuous cycling PD (CCPD): automated nocturnal exchanges using a cycler machine. Can use in addition to daytime CAPD. 

Management

• When a patient on peritoneal dialysis is admitted to the hospital, obtain a renal consult. Only nephrology can write PD orders.
• PD patients must be admitted to private rooms to ensure sterility of the exchanges. 

Complications

• Peritonitis: often see cloudy dialysate, fever, abdominal pain (usually severe), nausea and vomiting.
  • Send PD fluid for cell count with diff, gram stain, and culture, LDH, total protein.
    • Need to rapidly rule out secondary peritonitis from visceral perforation which is usually polymicrobial.
    • Secondary peritonitis criteria: PMN >250cells/mL + 2 or more of the following:
      • Total protein >1g/dL.
      • LDH >upper limit of normal for serum.
      • Glucose <50mg/dL (100% sensitive, 45% specific).
      • WBC count >100 with over 50% PMNs is strong evidence of peritonitis (note: this definition is different from SBP).
  • If cultures are negative, repeat PD fluid analysis at 3 days. Continue initial antibiotics if the patient is improving.
  • Treatment: empiric antibiotics are based on gram stain. If gram stain is negative (50%) cover for both gram positive cocci (50% of infections) with vancomycin or 1st generation cephalosporin and gram negative rods including Pseudomonas (15% of infections) with cefepime or an aminoglycoside. 20% of cultures are negative even with clear clinical evidence of peritonitis. 
    • Common bacteria: Staph epi, Staph aureus, Streptococcus (including Enterococcus best treated with IP ampicillin), E. coli, Pseudomonas, and Klebsiella. Tailor further therapy based on culture and sensitivity data.
    • Minimum therapy is two weeks; 3 weeks in severe infection, including Pseudomonas. Intraperitoneal dosing either once daily in a dwell of at least 6 hours or with all exchanges.
    • Admit for severe or recurrent infection, failure to respond to appropriate IP antibiotics, abscess, pain control, etc.
    • Repeat PD fluid analysis within 3-5 days to ensure appropriate decreased inflammatory signs.
  • Indications for PD catheter removal: fungal peritonitis, tuberculous peritonitis, refractory peritonitis (failure to clear effluent after appropriate antibiotics x 5d), relapsing peritonitis (recurrence in <4 weeks, same organism) or peritonitis in conjunction with tunnel infection. Removal may be required when S. aureus or Pseudomonas is present (unlikely to resolve without catheter removal).
• Hyperglycemia: common even in non-diabetic patients undergoing PD.
• Encapsulating peritoneal sclerosis: associated with severe malnutrition, with progressive obstruction and encapsulation of the bowel, often fatal. 

Philip Kam-Tao Li, C. et al. Peritoneal Dialysis-related Infections Recommendations: 2010 Update. Peritoneal Dialysis International, Vol. 30, pp. 393–423.

Teitelbaum I, Burkart J. Peritoneal dialysis. Am J Kidney Dis 2003;42:1082-1096.