Zacks S L, Fried M W
Division of Digestive Diseases and Nutrition, University of North Carolina at Chapel Hill, North Carolina, USA.
Infect Dis Clin North Am. 2001 Sep;15(3):877-99. doi: 10.1016/s0891-5520(05)70177-x.
Hepatitis C is the most common cause of liver disease in the dialysis patient. The prevalence of chronic hepatitis C determined by anti-HCV testing in this population ranges from 6% to 38%. Using second generation EIA assays, the prevalence of anti-HCV among patients participating in the 1997 National Surveillance of Dialysis Associated Diseases in the United States was 9.3%. Polymerase chain reaction testing for HCV RNA has shown that the prevalence of HCV infection can be as high as 20% to 30% of dialysis patients. The causes and source of infection in patients with chronic renal failure on hemodialysis are multiple. Before the introduction of routine screening of blood donors for anti-HCV, blood transfusions were an important risk factor for acquisition of hepatitis C. Other potential sources of infection include exposure to contaminated equipment and nosocomial routes such as patient-to-patient exposure. The risk of infection appears to correlate with the duration of hemodialysis and the number of transfusions. Interestingly, dialysate and buffers have been shown to be virus free even when used in hepatitis C infected patients. The natural history of chronic hepatitis C infection in patients with renal failure is not well characterized. Although persistent elevations in ALT levels occur in 12% to 50% of dialysis patients, the frequency of persistently normal ALT levels in HCV-infected dialysis patients appears to be higher than in HCV-infected patients without renal failure. Overt liver disease and liver failure rarely occur. The degree of inflammation in liver biopsies of renal failure patients is usually mild. Thus, progressive liver disease may be less common in patients with advanced renal disease but further studies are required to assess the true impact of hepatitis C infection in this high risk population. The impact of hepatitis C infection on morbidity and mortality of patients with end-stage renal disease remains poorly defined. Initial studies have failed to show a significant increase in mortality among HCV-infected hemodialysis or renal transplant patients within the first 5 years following transplantation. In contrast, recent studies with extended follow-up of renal transplant recipients suggest that hepatitis C infection may affect patient and graft survival during the second decade. Further studies are required to identify the mechanisms of infection of patients with end-stage renal disease and to define better treatment strategies for these patients before and after kidney transplantation.
丙型肝炎是透析患者肝病的最常见病因。通过抗-HCV检测确定的该人群慢性丙型肝炎患病率在6%至38%之间。使用第二代酶免疫分析方法，1997年美国透析相关疾病国家监测中参与的患者抗-HCV患病率为9.3%。对HCV RNA进行聚合酶链反应检测表明，HCV感染患病率在透析患者中可高达20%至30%。血液透析的慢性肾衰竭患者感染的原因和来源是多方面的。在对献血者进行常规抗-HCV筛查之前，输血是感染丙型肝炎的一个重要危险因素。其他潜在感染源包括接触受污染的设备以及医院内传播途径，如患者之间的接触。感染风险似乎与血液透析时间和输血次数相关。有趣的是，即使在丙型肝炎感染患者中使用，透析液和缓冲液也已被证明无病毒。肾衰竭患者慢性丙型肝炎感染的自然病程尚不明确。虽然12%至50%的透析患者ALT水平持续升高，但HCV感染的透析患者ALT水平持续正常的频率似乎高于无肾衰竭的HCV感染患者。明显的肝病和肝衰竭很少发生。肾衰竭患者肝活检中的炎症程度通常较轻。因此，进展性肝病在晚期肾病患者中可能不太常见，但需要进一步研究来评估丙型肝炎感染在这一高危人群中的真正影响。丙型肝炎感染对终末期肾病患者发病率和死亡率的影响仍不明确。初步研究未能显示HCV感染的血液透析或肾移植患者在移植后的前5年内死亡率显著增加。相比之下，最近对肾移植受者进行长期随访的研究表明，丙型肝炎感染可能在第二个十年影响患者和移植物存活。需要进一步研究以确定终末期肾病患者的感染机制，并为这些患者在肾移植前后确定更好的治疗策略。
