Late-onset systemic lupus erythematosus-associated liver disease.

Systemic lupus erythematosus (SLE) is a multisystemic autoimmune disease, which predominantly affects women under 50 years old. Although liver disease is not included in the diagnostic criteria, abnormal liver tests are common among patients with SLE and, in a significant proportion of those patients, no other underlying condition can be identified. We described a case of liver involvement in late-onset SLE presenting with a predominantly cholestatic pattern. Other conditions associated with abnormal liver tests were excluded, and the patient showed a prompt response to steroid therapy. The spectrum of the liver involvement in SLE is discussed, with emphasis on the differential diagnosis with autoimmune hepatitis.

YKL-40 and hyaluronic acid (HA) as noninvasive markers of liver fibrosis in kidney transplant patients with HCV chronic infection.

OBJECTIVE: Hepatitis C is highly prevalent among kidney transplant (KT) recipients. In this population, the natural history of hepatitis C virus (HCV) infection and its proper management remains controversial. The invasiveness of the procedure and the interpretation variability of liver biopsy limit its use in these patients. We sought to evaluate the performance of YKL-40 and HA as markers of liver fibrosis in KT patients with HCV infection. MATERIAL AND METHODS: This cross-sectional study included HCV infected KT individuals. Univariate analysis was used to identify variables associated with significant fibrosis (METAVIR >or= F2). The diagnostic values of the YKL-40 and HA were compared using receiver operating characteristic (ROC) curves. RESULTS: Eighty-five patients were included (60% males, mean age 44.9 +/- 9.4 years). Significant fibrosis was observed in 14 patients (17%). When compared to F0/F1 individuals, patients with significant fibrosis were older, showed a higher time since transplantation, and higher prevalence of diabetes. No difference was observed in YKL-40 levels between the groups. Significantly higher levels of HA were noted in METAVIR >or= F2 subjects (108 vs. 37 ng/ml, p = 0.002). The AUROCs of YKL-40 and HA for predicting significant fibrosis were 0.615 and 0.765, respectively (p = 0.144). Levels of YKL-40 or= 418 ng/ml and HA >or= 120 ng/ml exhibited a PPV of 31% and 39%, respectively. CONCLUSIONS: Increased serum levels of HA but not of YKL-40 were associated with more advanced stages of liver fibrosis in KT HCV-infected patients.

Clinical and histological impact of previous hepatitis B virus infection in patients with chronic hepatitis C.

BACKGROUND: Recent reports suggest that hepatitis C virus (HCV) carriers with serological markers of prior hepatitis B virus (HBV) infection have more advanced liver fibrosis, irrespective of HBV-DNA detection. AIMS: We sought to assess the prevalence and impact of previous HBV infection in patients with HCV chronic infection. METHODS: This cross-sectional study included hepatitis B surface antigen- and human immunodeficiency virus-negative subjects with positive HCV-RNA. All patients had prior parenteral exposure as the probable source of HCV infection. Serum samples were tested for HBV-DNA using a commercial assay. The METAVIR system was used for histological analysis. RESULTS: One-hundred and eleven patients were evaluated. Thirty-one out of 111 patients (28%) tested positive for antihepatitis B core antigen (anti-HBc). HBV-DNA was not detected in any sample. Anti-HBc-positive patients showed higher histological grading, staging and a higher fibrosis progression rate. By multivariate analysis, anti-HBc-positivity was predictive of moderate to severe activity [odds ratio (OR)=3.532; P=0.032] and significant hepatic fibrosis (OR=3.364; P=0.017). After approximately 20 years of infection, advanced liver fibrosis (F3/F4) can be expected in 13% of anti-HBc-negative subjects who acquired HCV before the age of 30 and in 57% of those anti-HBc-positive patients who were infected by HCV after 30 years of age (P<0.001). CONCLUSION: Previous HBV infection is common among HCV carriers and may exert a negative impact on the natural history of HCV infection, independently of the presence of significant HBV replication.

Changing pattern of chronic hepatitis C in renal transplant patients over 20 years.

BACKGROUND: The prevalence and clinical epidemiological profile of hepatitis C virus (HCV) infection have changed over time. AIM: This study aimed to evaluate these changes in renal transplant recipients (RTx) comparing two different decades. MATERIALS AND METHODS: RTx with HCV referred to RTx from 1993 to 2003 (A) and from 2004 to 2014 (B) were studied retrospectively. The demographic and clinical characteristics and different outcomes were compared between groups A and B. Variables that were statistically different were tested for inclusion in a multivariate Cox proportional hazard model predicting patient survival within the group. RESULTS: Among 11 715 RTx, the prevalence of HCV was 7% in A and 4.9% in B. In the more recent period (B), the mean age was older (46.2 vs. 39.5 years), with more males (72 vs. 60.7%), larger number of deceased donors (74 vs. 55%), higher percentage of previous RTx (27 vs. 13.7%), less frequent history of blood transfusion (81 vs. 89.4%), lower prevalence of hepatitis B virus coinfection (4.7 vs. 21.4%), and higher percentage of cirrhotic patients (13 vs. 5%). Patients of group B more frequently underwent treatment of HCV (29 vs. 9%), less frequently used azathioprine (38.6 vs. 60.7%) and cyclosporine (11.8 vs. 74.7%), and more frequently used tacrolimus (91 vs. 27.3%). In the outcomes, graft loss showed no difference between periods; however, decompensation was more frequent (P = 0.007) and patients' survival was lower in the more recent period (P = 0.032) compared with the earlier one. CONCLUSION: The profile of RTx with HCV has changed over the last 20 years. Despite a decrease in the prevalence of HCV, new clinical challenges have emerged, such as more advanced age and a higher prevalence of cirrhosis.

Optimized cutoffs improve performance of the aspartate aminotransferase to platelet ratio index for predicting significant liver fibrosis in human immunodeficiency virus/hepatitis C virus co-infection.

AIM: To assess the diagnostic value of modified cutoffs for aspartate aminotransferase to platelet ratio index (APRI) to predict significant liver fibrosis in human immunodeficiency virus (HIV)/hepatitis C virus (HCV) patients. PATIENTS AND METHODS: This retrospective cross-sectional study included consecutive patients with HIV/HCV co-infection who underwent percutaneous liver biopsy. The accuracy of APRI for the diagnosis of significant fibrosis (F2/F3/F4 METAVIR) was evaluated by estimating the positive and negative predictive values (PPV and NPV respectively) and by measuring the area under the receiver operating characteristics curve (AUROC). RESULTS: One hundred and eleven patients were included (73% men, mean age 40.2+/-7.8 years). Significant fibrosis was observed in 45 patients (41%). To discriminate these subjects, the AUROC of APRI was 0.774+/-0.045. An APRI > or = 1.8 showed a PPV of 75% for the presence of significant fibrosis, and an index < 0.6 excluded significant fibrosis with an NPV of 87%. If biopsy indication was based only on APRI and restricted to scores in the intermediate range (> or = 0.6 and < 1.8), 46% of liver biopsies could have been avoided as compared with 40% using the classical cutoffs. CONCLUSION: APRI with adjusted cutoffs can predict significant liver fibrosis in patients with HIV/HCV co-infection and might obviate the need to perform a biopsy in a considerable percentage of those subjects.

Hepatitis C in chronic kidney disease: predialysis patients present more severe histological liver injury than hemodialysis patients?

BACKGROUND: The characteristics of hepatitis C virus (HCV) infection in predialysis patients are poorly understood and they could be different from hemodialysis patients. AIMS: To evaluate the demographics, laboratory and histological characteristics of chronic HCV infection in predialysis patients and to compare them with those observed in hemodialysis patients. METHODS: Thirty-nine predialysis patients with chronic HCV infection were compared to HCV-infected hemodialysis patients (ratio of 1:3) in terms of demographics, laboratory and histological characteristics. The fibrosis progression rate (FPR) was calculated as the ratio between fibrosis stage and duration of infection. RESULTS: Predialysis patients were older (57 +/- 10 vs. 45 +/- 12 years; p < 0.001), presented a higher proportion of elevated alanine aminotransferase (71.8 vs. 41.0%; p = 0.001) and aspartate aminotransferase (64.1 vs. 26.5%; p < 0.001), a higher proportion of interface hepatitis (66.7 vs. 47%; p = 0.033) and more advanced fibrosis (71.8 vs. 16.2%; p = 0.001). Among patients with estimated duration of infection, predialysis patients presented a longer duration of infection (22 vs. 6 years; p < 0.001) and no difference in FPR was observed between groups (p = 0.692). CONCLUSION: Although predialysis patients with HCV infection present more severe histological injury than hemodialysis patients, this finding probably reflects a longer duration of infection with no evidence supporting that hepatitis C presents a more aggressive course in this group.

Cutaneous amyloidosis associated with primary biliary cirrhosis.

Primary cutaneous amyloidosis is defined as the deposition of amyloid in the skin in the absence of systemic involvement. The association between primary cutaneous amyloidosis and other diseases, although rare, has been documented for connective tissue disorders such as systemic sclerosis, systemic lupus erythematosus and rheumatoid arthritis. We report the case of a 41-year-old woman who developed primary biliary cirrhosis in association with primary cutaneous amyloidosis. This association has not been reported before in the literature.

Factors associated with the intensity of liver fibrosis in renal transplant patients with hepatitis B virus infection.

BACKGROUND: Hepatitis B may show a more aggressive course after kidney transplantation, but the factors associated with the progression of fibrosis in this group have not been identified. OBJECTIVES: To determine the influence of hepatitis B virus (HBV) viral load and host-related factors on the progression of hepatic fibrosis in hepatitis B virus-infected renal transplant recipients. PATIENTS AND METHODS: Renal transplant patients positive for HBV surface antigen (HBsAg) and submitted to a liver biopsy because of evidence of viral replication were included. Patients with advanced fibrosis (METAVIR F3-F4) were compared with patients with mild fibrosis (F0-F2) regarding sex, age, estimated time since infection, post-transplant time, donor type, history of renal transplantation, alanine aminotransferase, anti-hepatitis C virus, HBeAg and quantitative hepatitis B virus-DNA. Logistic regression analysis was applied to identify variables independently associated with more advanced fibrosis. RESULTS: Fifty-five patients (75% men, 41+/-11 years) with a mean post-transplant time of 5+/-4 years were included. HBeAg was detected in 67% of the patients and anti-hepatitis C virus in 35%. The median hepatitis B virus-DNA level was 2.8 x 10(8) copies/ml. Seventeen (31%) patients had advanced fibrosis. Using logistic regression analysis, the only variable that showed an independent association with more advanced stages of fibrosis was post-transplant time (P=0.03, odds ratio: 1.2, 95% confidence interval: 1.02-1.45). CONCLUSION: Hepatitis B virus viral load, although very high, and hepatitis B virus/hepatitis C virus coinfection are not related to the intensity of liver fibrosis in renal transplant patients infected with hepatitis B virus. Post-transplant time was the only factor independently associated with more advanced liver fibrosis, suggesting the influence of immunosuppression on the progression of liver disease in these patients.

Determination of alanine aminotransferase in blood donor screening--evidence of its usefulness in the prevention of post-transfusion hepatitis.

A total of 408 HBsAg and anti-HCV-negative patients with elevated ALT levels referred from blood banks were studied. Of these, 359 were followed up. HBsAg and anti-HCV were repeated in the first visit and ALT was checked at a 3 months interval. A liver biopsy was indicated when ALT levels remained abnormal for more than 6 months. Of the patients included, 316/359 (88%) were men, with a mean age of 34 years. In the first visit, 3 (0.8%) patients were anti-HCV positive upon serological reevaluation, with persistence of elevated ALT in all of them. A biopsy revealed chronic hepatitis in all three cases. Twenty-two patients were positive for anti-HBc, 20 of them were immune (anti-HBs positive), one developed anti-HBs after a vaccine dose, and one was HBsAg positive. The present study suggests that ALT can be a useful marker for the detection of hepatitis C virus infected donors in whom technical problems might have occurred in serological screening.

Effect of host-related factors on the intensity of liver fibrosis in patients with chronic hepatitis C virus infection.

There is increasing interest in the identification of factors associated with liver disease progression in patients infected with hepatitis C virus (HCV). We assessed host-related factors associated with a histologically advanced stage of this disease and determined the rate of liver fibrosis progression in HCV-infected patients. We included patients submitted to liver biopsy, who were anti-HCV and HCV RNA positive, who showed a parenteral risk factor (blood transfusion or intravenous drug use), and who gave information about alcohol consumption. Patients were divided into two groups for analysis: group 1 - grades 0 to 2; group 2 - grades 3 to 4. The groups were compared in terms of sex, age at the time of infection, estimated duration of infection and alcoholism. The rate of fibrosis progression (index of fibrosis) was determined based on the relationship between disease stage and duration of infection (years). Logistic regression analysis revealed that age at the time of infection (P<0.01; 95% CI 1.06-1.22) and the duration of infection (P<0.01; 95% CI 1.06-1.32) were independently associated with a more advanced stage of hepatitis C. The median index of fibrosis was 0.14 for the group as a whole. A significant difference in the index of fibrosis was observed between patients aged < 40 years at infection (median = 0.11) and patients aged > or = 40 years (median = 0.47). The main factors associated with a more rapid fibrosis progression were age at the time of infection and the estimated duration of infection. Patients who acquired HCV after 40 years of age showed a higher rate of fibrosis progression.

Crohn's disease versus Yersinia enterocolitica infection - case report - a difficult differential diagnosis / Doença de Crohn's × Yersinia enterocolitica - um difícil diagnóstico diferencial - relato de caso

ABSTRACT The aim of this report is to present an unusual case of Crohn's disease affecting the terminal ileum; whose principal differential diagnosis was Yersinia enterolocolitica infection, as the histological features of the resected ileum was common to both diseases. We also describe how the infectious etiology was discarded and the implications for the patient follow-up.

RESUMO O objetivo desse relato é analisar um caso incomum de doença de Crohn, cujo diagnóstico diferencial, com possível infecção por Yersinia enterocilítica, foi dificultado pela presença de alterações histológicas das duas doenças. Descrevemos como foi realizada a exclusão de causas infecciosas e as implicações no acompanhamento do paciente.

Altered glucose homeostasis and hepatic function in obese mice deficient for both kinin receptor genes.

The Kallikrein-Kinin System (KKS) has been implicated in several aspects of metabolism, including the regulation of glucose homeostasis and adiposity. Kinins and des-Arg-kinins are the major effectors of this system and promote their effects by binding to two different receptors, the kinin B2 and B1 receptors, respectively. To understand the influence of the KKS on the pathophysiology of obesity and type 2 diabetes (T2DM), we generated an animal model deficient for both kinin receptor genes and leptin (obB1B2KO). Six-month-old obB1B2KO mice showed increased blood glucose levels. Isolated islets of the transgenic animals were more responsive to glucose stimulation releasing greater amounts of insulin, mainly in 3-month-old mice, which was corroborated by elevated serum C-peptide concentrations. Furthermore, they presented hepatomegaly, pronounced steatosis, and increased levels of circulating transaminases. This mouse also demonstrated exacerbated gluconeogenesis during the pyruvate challenge test. The hepatic abnormalities were accompanied by changes in the gene expression of factors linked to glucose and lipid metabolisms in the liver. Thus, we conclude that kinin receptors are important for modulation of insulin secretion and for the preservation of normal glucose levels and hepatic functions in obese mice, suggesting a protective role of the KKS regarding complications associated with obesity and T2DM.

Is autoimmune hepatitis a frequent finding among HCV patients with intense interface hepatitis?

AIM: To evaluate the overlap of autoimmune hepatitis in hepatitis C virus (HCV)-infected patients with intense interface hepatitis. METHODS: Among 1759 patients with hepatitis C submitted to liver biopsy, 92 (5.2%) presented intense interface hepatitis. These patients were evaluated regarding the presence of antinuclear antibody (ANA), anti-smooth muscle antibody (SMA) and anti-liver/kidney microsomal antibody (LKM-1), levels of gamma-globulin and histological findings related to autoimmune hepatitis (plasma cell infiltrate and presence of rosettes). RESULTS: Among patients with hepatitis C and intense interface hepatitis there was a low prevalence of autoantibodies (ANA = 12%, SMA = 5%, LKM-1 = 0%) and the median gamma-globulin level was within the normal range. Typical histological findings of autoimmune disease were observed in only two cases (2%). After applying the score for diagnosis of autoimmune hepatitis, only one patient was classified with a definitive diagnosis of autoimmune hepatitis. Since overlap with autoimmune hepatitis was not the explanation for the intense necroinflammatory activity in patients with chronic hepatitis C we sought to identify the variables associated with this finding. The presence of intense interface hepatitis was associated with more advanced age, both at the time of infection and at the time of the biopsy, and higher prevalence of blood transfusion and alcohol abuse. CONCLUSION: Although possible, overlap with autoimmune hepatitis is a very rare association in HCV-infected patients with intense interface hepatitis, an unusual presentation which seems to be related to other host variables.

Factors associated with the progression of hepatic fibrosis in end-stage kidney disease patients with hepatitis C virus infection.

BACKGROUND: Few studies have evaluated the histological aspects of hepatitis C virus (HCV) infection in hemodialysis patients and the factors related to the progression of hepatic fibrosis in this population have not been defined. AIM: To evaluate the influence of host-related factors on the fibrosis progression in end-stage renal disease (ESRD) patients with HCV infection. METHODS: HCV-infected ESRD patients who submitted to liver biopsy were included. The fibrosis stages were classified according to METAVIR scoring system. For the identification of factors associated with more advanced liver fibrosis, the patients were classified into two groups: group 1, absence of septal fibrosis (F0-1) and group 2, presence of septal fibrosis (F2-4). Groups 1 and 2 were compared regarding demographic, epidemiological, and laboratory variables and logistic regression analysis was used to identify the variables that were independently associated with the presence of septal fibrosis. RESULTS: A total of 216 ESRD patients (63% men, 44+/-11 years) were included. In the histological analysis, the fibrosis stages were as follows: F0=36%, F1=41%, F2=12%, F3=7, and 4% had cirrhosis (F4). In the logistic regression model, the variables that were independently associated with the presence of septal fibrosis were duration of infection, estimated age at infection, coinfection with HBV and aspartate aminotransferase levels. CONCLUSION: These findings support the importance of obtaining an adequate immune response to HBV vaccination and careful monitoring of liver disease in patients who become infected at an advanced age and/or those presenting elevated aspartate aminotransferase levels, as these are the main factors associated with the presence of septal fibrosis in ESRD patients.

Simple blood tests as noninvasive markers of liver fibrosis in hemodialysis patients with chronic hepatitis C virus infection.

UNLABELLED: HCV infection is common among patients with end-stage renal disease (ESRD) on hemodialysis, and it has been considered an independent risk factor for mortality in this setting. Although liver biopsy in ESRD patients with HCV infection is useful before kidney transplantation, it carries a high risk of complications. We sought to assess the diagnostic value of noninvasive markers to stage liver fibrosis in 203 ESRD HCV-infected patients. Univariate and multivariate analysis were used to identify variables associated with significant fibrosis (METAVIR F2, F3, or F4 stages). Significant liver fibrosis was observed in 48 patients (24%). Logistic regression analysis identified AST and platelet count as independent predictors of significant fibrosis (P < 0.001 and P = 0.001, respectively). The area under the receiver operating characteristic curve of the AST to platelet ratio index (APRI) for predicting significant fibrosis was 0.801. An APRI < 0.40 accurately identified patients with fibrosis stage 0 or 1 in 93% of the cases (NPV = 93%), and all misclassified subjects were F2. A cutoff > or = 0.95 to confirm significant fibrosis had a PPV of 66%. If biopsy indication was restricted to APRI scores in the intermediate range (> or = 0.40 and < 0.95), 52% of liver biopsies could have been correctly avoided. CONCLUSION: Stage of liver fibrosis can be reliably predicted in ESRD HCV-infected subjects by simple and widely available blood tests such as AST levels and platelet count. These tests might obviate the requirement for a liver biopsy in a significant proportion of those patients.

Is hepatitis C more aggressive in renal transplant patients than in patients with end-stage renal disease?

BACKGROUND: The eventual impact of immunosuppression on the natural history of hepatitis C virus (HCV) infection in patients with end-stage renal disease (ESRD) is still unknown because of the lack of comparative data for HCV-infected patients with ESRD and renal transplant patients. The aim of this study was to compare the biochemical and histological characteristics of chronic HCV infection in renal transplants patients and ESRD patients undergoing hemodialysis. METHODS: Thirty-eight renal transplant patients and 38 ESRD patients undergoing hemodialysis who were chronically infected with HCV and were matched for gender, age at infection, and estimated time of infection were included in the study. The groups were compared regarding laboratory and histological variables. RESULTS: Renal transplant patients showed similar alanine aminotransferase and higher gamma-glutamyltransferase levels (P = 0.05) when compared with ESRD patients. Comparative analysis of histological variables revealed a higher proportion of cases with septal fibrosis (P = 0.04) and confluent necrosis (P = 0.01) among transplant-recipient patients. No difference between groups was observed regarding the intensity of portal and periportal inflammatory infiltrates. Steatosis was more prevalent among transplant-recipient patients (P < 0.001). There was no difference between groups regarding the prevalence of lymphoid aggregates or bile duct injury. CONCLUSION: Renal transplant patients had a larger proportion of cases with septal fibrosis and confluent necrosis than did ESRD patients, suggesting that renal transplantation might modify the natural history of hepatitis C in ESRD patients, leading to a more aggressive liver disease.

Efficacy and tolerance of interferon-alpha in the treatment of chronic hepatitis C in end-stage renal disease patients on hemodialysis.

BACKGROUND: Patients with end-stage renal disease (ESRD) show a high prevalence of hepatitis C, with a negative impact on the survival on hemodialysis and after renal transplantation. We evaluated the efficacy and tolerance of interferon-alpha (IFN-alpha) in HCV-infected ESRD patients on dialysis. METHODS: Forty-six HCV-RNA-positive ESRD patients were studied. IFN-alpha regimen consisted of 3 million units three times a week for 12 months, and the patients were followed up for 6 months. End-of-treatment, and sustained biochemical and virological responses were evaluated and tolerance was assessed monthly. RESULTS: A sustained virological response (SVR) was observed in 10/46 patients (22%) and in 10/29 who completed the treatment (34%). Alanine aminotransferase was elevated in 63% of the patients at the beginning of the study and returned to normal levels within the first month in all patients with SVR. Treatment was discontinued because of side effects in 11/46 patients (24%) and six patients (13%) were lost to follow-up. CONCLUSIONS: IFN-alpha monotherapy for hepatitis C in dialysis patients shows a high frequency of adverse effects. However, the SVR is high (34%) in patients who complete treatment, emphasizing the importance of careful selection and close follow-up in order to minimize and control possible side effects.

Steatosis in chronic hepatitis C: relationship to the virus and host risk factors.

BACKGROUND: Steatosis occurs frequently in hepatitis C. However, the mechanisms leading to this lesion are still unknown, and the role of steatosis in the progression of the disease remains controversial. The aim of the present paper was to determine the prevalence of steatosis in hepatitis C and its association with hepatitis C virus (HCV) genotype, viral load and the presence of risk factors for steatosis, and to analyze the association between steatosis and the intensity of liver disease. METHODS: Patients infected with HCV who underwent liver biopsy were included. Patients coinfected with hepatitis B virus and/or human immunodeficiency virus and those previously treated for hepatitis C were excluded. The following risk factors for steatosis were investigated: obesity (body mass index [BMI] > 25 kg/m(2)), diabetes mellitus, hyperlipidemia, alcoholism, and use of potential steatosis-inducing drugs. Histological analysis evaluated the presence of steatosis, the degree of periportal activity and staging. Patients with and without steatosis were compared regarding demographic, epidemiological, laboratory and histological characteristics. Logistic regression analysis was applied to identify variables that were independently associated with the presence of steatosis. RESULTS: Ninety patients (55 men, 35 women) with a mean age of 45 +/- 13 years were included. The prevalence of steatosis was 67%. Variables that remained independently associated with steatosis were age, female gender, obesity and genotype 3. CONCLUSIONS: The prevalence of steatosis in hepatitis C was high. Risk factors usually related to steatosis such as age, female gender and obesity, as well as genotype 3, were independently associated with the presence of steatosis. Steatosis was not independently associated with the intensity of histological liver disease.

Hepatitis C virus infection in renal transplant patients: a comparative study with immunocompetent patients.

The behavior of hepatitis C in states of immunodeficiency is poorly understood and it is still unclear whether the characteristics of hepatitis C virus (HCV) infection in renal transplant patients differ from those observed in immunocompetent subjects. The aim of this study was to compare the biochemical and histologic characteristics of chronic HCV infection between renal transplant and immunocompetent patients. Forty-one HCV-RNA-positive renal transplant patients and 41 immunocompetent controls matched for gender, age at infection and time of infection were included in the study. The groups were compared regarding laboratory and histologic variables. Renal transplant patients showed lower alanine aminotransferase (ALT) levels (p = 0.005) and higher levels of gamma-glutamyltransferase (p = 0.003), alkaline phosphatase (p < 0.001), and direct bilirubin (p < 0.001) when compared with controls. Histologic analysis revealed less intense portal (p < 0.001) and periportal (p = 0.046) inflammatory infiltrate in renal transplant patients but a larger proportion of cases with confluent necrosis (p = 0.043). No difference in the presence of septal fibrosis, hepatic steatosis, bile duct injury and siderosis was observed. However, there was a difference in the presence of lymphoid aggregates, which were less frequent in the renal transplant group (p < 0.001). In conclusion, the characteristics of hepatitis C in renal transplant patients differ from that observed in immunocompetent patients. In renal transplant patients, HCV infection is biochemically characterized by lower ALT levels and higher frequency of cholestasis. Regarding histology, despite lower frequency of lymphoid aggregates and less intense portal/periportal inflammatory infiltrate, a greater lobular damage was observed. The impact of these differences on the progression of fibrosis remains to be established.