Peritoneal dialysis in liver disorders

The purposes of this paper is to review the specific role of peritoneal dialysis (PD) in patients with liver disorders. We will pay attention to the confluence of liver diseases and situations for which chronic dialysis treatment is required. Hemodialysis (HD) and peritoneal membranes are safe barriers against the passage of the hepatitis C virus; consequently, while peritoneal effluent or HD ultrafiltrate drained from hepatitis B patients/carriers is infective, that from hepatitis C patients does not appear to present this risk. An important issue is horizontal transmission, which appears to occur with both viruses in HD units, and which is absent in peritoneal dialysis units. The incidence of hepatitis C among continuous ambulatory peritoneal dialysis (CAPD) patients is quite low, while it may reach almost 50%-60% of HD patients in some units. While hepatitis C transmission mechanisms are not completely understood and a vaccine is not available, PD provides some degree of protection when compared with HD, for and-stage renal disease patients. In summary, our experience and that of others, with a total of 19 PD-treated chronic liver disease patients, supports CAPD as the treatment of choice for cirrhotic patients with ascites who require chronic dialysis. Data on peritoneal diffusion of low molecular weight substances revealed a marked increase in most patients. The ultrafiltration capacity was clearly augmented with respect to noncirrhotic patients, making the use of hypertonic bags unnecessary. Hemodynamic tolerance was excellent. Complications and death were mainly related to liver disease complications. Spontaneous bacterial peritonitis (SBP), caused by gram-negative germs, is the most important complication directly related to ascites and may have some points in common with PD-related peritonitis. However, and in contrast to most PD peritonitis, two pathogenetic mechanisms have been suggested for SBP: (1) translocation of bacteria from the gut to the mesenteric lymph nodes, and (2) bacteremia in these patients is secondary to the general abnormal host defense mechanisms. Local factors such as intrahepatic shunting and the impairment of bactericidal activity in ascitic fluid favor the bacteria ascites. The hypothesis of a direct transmural contamination from bowel to ascitic fluid has been relegated to secondary bacterial peritonitis. Would cirrhotic patients with temporal or permanent renal function compromise benefit from peritoneal catheter placement and other PD practices to perform repetitive small ascitic drainages at home? Perhaps the time has arrived when hepatologists and PD nephrologists begin to work shoulder to shoulder in this particular field, as we have a common problem, the peritoneal cavity filled with fluid.