Viral hepatitis in elderly haemodialysis patients: current prevention and management strategies.

Viral hepatitis continues to be a relevant topic for haemodialysis centres, although the number of infected dialysis patients is declining in most countries. Chronic hepatitis B and C lead to detrimental complications such as liver cirrhosis and hepatocellular carcinoma. These complications can be avoided by successful antiviral treatment. In individuals with normal renal function, drug therapy of chronic hepatitis B is evolving quickly. Today there are several options but no agreed standard therapy. In the absence of renal failure, chronic hepatitis C should be treated with a combination of pegylated interferon-alpha and ribavirin. For both infections, there is no general indication to treat all patients; several criteria can be used to predict benefits and downsides. Chronic renal failure severely alters immune function, particularly activation of T lymphocytes and cytokine production by mononuclear cells. Aging further influences the immune system with deviation of T-lymphocyte differentiation. Both effects seem to act additively, leaving the elderly haemodialysis patient with extensive immune dysfunction. While these effects do not put the patient at risk of opportunistic infection, they do have a relevant effect on the clinical course of viral hepatitis. Haemodialysis patients infected with hepatitis B manifest a subclinical, often anicteric disease, and at least 60% of the infections become chronic. These patients usually do not fulfil the criteria for successful antiviral treatment, since they have normal or slightly elevated liver enzyme levels and few histological signs of liver inflammation. In addition, the prognosis in terms of cirrhosis and hepatocellular carcinoma might be more favourable than in individuals with normal renal function. The former standard treatment of chronic hepatitis B with interferon-alpha or its derivate pegylated interferon was badly tolerated in dialysis patients and associated with low efficacy. Indeed, prior to the advent of nucleoside analogues there was a clear recommendation not to treat chronic hepatitis B infection in all except a few dialysis patients. However, the newer treatment options appear to work well. In particular, there is growing evidence for the effectiveness and tolerability of lamivudine in dialysis patients, including the elderly. Use of adefovir and entecavir has also been reported in a few cases. At present, while we still do not recommend treatment, therapy with nucleoside analogues might be an option in selected patients, for example, those planning renal transplantation. The major effort against hepatitis B should be directed at vaccination and hygienic precautions to prevent the infection.Treatment of hepatitis C in patients undergoing haemodialysis is also limited by the poor tolerability of interferons. Ribavirin is contraindicated because of severe haemolytic anaemia, although a few studies have attempted to manage this with administration of high doses of erythropoetin. Those patients who complete the full course of interferon therapy may expect sustained viral responses comparable with healthy individuals, but in most trials, 30-50% of patients were forced to interrupt treatment because of adverse effects. There is no general indication to treat chronic hepatitis C in haemodialysis patients. Arguments in favour of treatment include elevated liver enzymes, histological signs of relevant liver inflammation, younger age, a virus genotype other than 1 and planned renal transplantation.