Fabrizi F, Lunghi G, Finazzi S, Colucci P, Pagano A, Ponticelli C, Locatelli F
Division of Nephrology and Dialysis, Institute of Hygiene and Preventive Medicine, Maggiore Hospital, Milano, Italy.
Am J Kidney Dis. 2001 Nov;38(5):1009-15. doi: 10.1053/ajkd.2001.28590.
Hepatitis C virus (HCV) infection is common in the dialysis population and patients with chronic renal failure (CRF) not requiring dialysis. HCV is the most important cause of chronic liver disease in dialysis patients; however, its role has been underestimated by the lower aminotransferase activity in the dialysis population. Aminotransferase activity in patients with CRF not requiring dialysis has not been adequately addressed to date. The aim of this study is to investigate whether serum aminotransferase levels in predialysis patients with CRF are less than those obtained in healthy individuals and dialysis patients. We also analyzed the potential association between serum aminotransferase activity and demographic, clinical, and biochemical parameters. Aspartate (AST) and alanine aminotransferase (ALT) activity was greater in antibody to hepatitis C (anti-HCV)-positive than anti-HCV-negative patients with CRF not requiring dialysis (AST, 32.3 +/- 19 versus 18.1 +/- 8 IU/L [P = 0.0001]; ALT, 32.9 +/- 28 versus 17.7 +/- 11 IU/L [P = 0.00001], respectively). Predialysis patients with CRF had lower AST and ALT activity in comparison to healthy individuals (AST, 19.7 +/- 11.2 versus 20.4 +/- 6.8 IU/L [P = 0.00001]; ALT, 19.5 +/- 15.1 versus 21.7 +/- 11.3 IU/L [P = 0.00001], respectively). The difference was much greater after correction for viral markers: AST and ALT levels in hepatitis B surface antigen (HBsAg)-negative anti-HCV-negative predialysis patients with CRF were less than those in the healthy population (AST, 17.9 +/- 8 versus 20.4 +/- 6.8 IU/L [P = 0.00001]; ALT, 17.5 +/- 10 versus 21.7 +/- 11.3 IU/L [P = 0.00001], respectively). Comparison of AST and ALT activity between age-matched healthy and predialysis seronegative CRF groups showed lower AST and ALT values in the study population. HBsAg-negative anti-HCV-negative dialysis patients had lower AST and ALT activity than seronegative predialysis patients with CRF (AST, 16.6 +/- 11.6 versus 17.9 +/- 8 IU/L [P = 0.01]; ALT, 16.3 +/- 9.4 versus 17.5 +/- 10 [P = 0.041], respectively). Multivariate analysis in the predialysis CRF population showed an independent association between AST (P = 0.00001) and ALT (P = 0.00001) activity and anti-HCV positivity, and age was negatively linked to AST (P = 0.011) and ALT levels (P = 0.001). AST level was negatively related to serum creatinine level (P = 0.0001). In conclusion, HCV infection causes significant liver injury in predialysis patients with CRF. These patients have decreased aminotransferase activity compared with the general population. Dialysis patients show lower aminotransferase activity than predialysis patients with CRF. Because serum aminotransferase levels are commonly used to screen for liver disease in the dialysis and predialysis CRF population, recognition of liver damage may be hampered by the reduction in aminotransferase values in these patients. Studies aimed to clarify the pathogenesis of this phenomenon are in progress.
丙型肝炎病毒(HCV)感染在透析人群以及不需要透析的慢性肾衰竭(CRF)患者中很常见。HCV是透析患者慢性肝病的最重要病因;然而,由于透析人群中氨基转移酶活性较低,其作用一直被低估。迄今为止,尚未充分探讨不需要透析的CRF患者的氨基转移酶活性情况。本研究的目的是调查未透析的CRF患者的血清氨基转移酶水平是否低于健康个体和透析患者。我们还分析了血清氨基转移酶活性与人口统计学、临床和生化参数之间的潜在关联。在不需要透析的抗丙型肝炎病毒(抗-HCV)阳性的CRF患者中,天冬氨酸氨基转移酶(AST)和丙氨酸氨基转移酶(ALT)活性高于抗-HCV阴性患者(AST分别为32.3±19与18.1±8 IU/L [P = 0.0001];ALT分别为32.9±28与17.7±11 IU/L [P = 0.00001])。与健康个体相比,未透析的CRF患者的AST和ALT活性较低(AST分别为19.7±11.2与20.4±6.8 IU/L [P = 0.00001];ALT分别为19.5±15.1与21.7±11.3 IU/L [P = 0.00001])。校正病毒标志物后差异更大:乙肝表面抗原(HBsAg)阴性且抗-HCV阴性的未透析CRF患者的AST和ALT水平低于健康人群(AST分别为17.9±8与20.4±6.8 IU/L [P = 0.00001];ALT分别为17.5±10与21.7±11.3 IU/L [P = 0.00001])。年龄匹配的健康人群与未透析的血清阴性CRF组之间的AST和ALT活性比较显示,研究人群中的AST和ALT值较低。HBsAg阴性且抗-HCV阴性的透析患者的AST和ALT活性低于血清阴性的未透析CRF患者(AST分别为16.6±11.6与17.9±8 IU/L [P = 0.01];ALT分别为16.3±9.4与17.5±10 [P = 0.041])。未透析的CRF人群的多变量分析显示,AST(P = 0.00001)和ALT(P = 0.00001)活性与抗-HCV阳性独立相关,且年龄与AST(P = 0.011)和ALT水平(P = 0.001)呈负相关。AST水平与血清肌酐水平呈负相关(P = 0.0001)。总之,HCV感染在未透析的CRF患者中导致显著的肝损伤。与普通人群相比,这些患者的氨基转移酶活性降低。透析患者的氨基转移酶活性低于未透析的CRF患者。由于血清氨基转移酶水平通常用于筛查透析和未透析的CRF人群中的肝病,这些患者氨基转移酶值的降低可能会妨碍对肝损伤的识别。旨在阐明这一现象发病机制的研究正在进行中。