ABSTRACT
<p><b>OBJECTIVE</b>To investigate the prevalence of antinuclear antibodies (ANA) and anti-liver/ kidney microsomal type 1 antibodies (anti-LKM1) in patients with chronic hepatitis C (CHC)and to explore the mechanism of production of these autoantibodies.</p><p><b>METHODS</b>Serum samples were collected from 360 patients with CHC (case group), 69 patients with chronic hepatitis B (CHB) and 69 patients with autoimmune hepatitis (AIH) (control group). Serum ANA and anti-LKM1 were detected by indirect immunofluorescence (HF) technique and enzyme-linked immunosorbent assay (ELISA), respectively. Multi-factor analysis was performed to explore the correlations of the production of autoantibodies with some factors such as age, sex, viral loads, HCV genotype, biochemical parameters and clinical characteristics.</p><p><b>RESULTS</b>Fifty-four (15%) of 360 patients infected with HCV were positive in autoantibodies. The prevalence of ANA and anti-LKM1 were 12.5% (45/360) and 2.5% (9/ 360), respectively. The positive rate of autoantibodies in patients with CHC was significantly higher than that in patients with CHB (15% vs 2.9%, P = 0.006), but significantly lower than that in patients with AIH (15% vs 47.9%, P < 0.001). Twenty-one (11.35%) of 185 male patients and 33 (18.86%) of 175 female patients were positive in autoantibodies, the difference in positive rate was significant (P < 0.05). HCV virus loads in the autoantibodies negative group were higher than that in the autoantibodies positive group (7.2 x 10(7) copies/L vs 1.23 x 10(7) copies/L, P < 0.05). There were not significant differences in age and genotype between the autoantibody positive group and the autoantibody negative group. The serum biochemical parameters of the autoantibody positive group were similar to those of the autoantibody negative group. The differences were not significant for the course of disease, clinical symptom, the incidence of cirrhosis between the autoantibody positive group and the autoantibody negative group. The prevalence of autoantibodies was not different for patients with or without interferon treatment (P > 0.05).</p><p><b>CONCLUSION</b>Autoantibodies related to AIH can be detected in CHC patients; interferon may not induce the production of autoantibodies; it is very likely that HCV infection induces the autoimmune reaction and the production of autoantibodies.</p>
Subject(s)
Adult , Female , Humans , Male , Middle Aged , Antibodies, Antinuclear , Blood , Allergy and Immunology , Autoantibodies , Blood , Allergy and Immunology , Hepatitis C, Chronic , Blood , Allergy and Immunology , VirologyABSTRACT
<p><b>BACKGROUND</b>Hepatitis C virus (HCV) infection may induce autoimmune response and autoantibodies can be detected in chronic hepatitis C (CHC) patients. However, the reported positive rate of autoantibodies in CHC patients in China varies considerably. In this study, we investigated the prevalence of antinuclear antibodies (ANA) and anti-liver-kidney-microsome type 1 autoantibodies (anti-LKM-1) in a large cohort of CHC patients, and analyzed the factors related to the presence of the autoantibodies.</p><p><b>METHODS</b>A total of 360 CHC patients were enrolled in this study. Serum ANA and anti-LKM-1 were detected by indirect immunofluorescence and enzyme-linked immunosorbent assay, respectively. Clinical analysis was performed to disclose the related factors to autoantibody production.</p><p><b>RESULTS</b>The prevalence of ANA and anti-LKM-1 in CHC patients was 12.5% (45/360) and 2.5% (9/360), respectively. Women had a higher prevalence than men (18.9% vs 11.4%, P = 0.046). Patients with positive autoantibodies had lower HCV RNA levels (1.2 x 10(7) copies/L vs 7.2 x 10(7) copies/L, P < 0.05). Positive ANA was associated with higher serum globulin (P < 0.05). Stratified analysis showed that there were no significant differences in age, HCV genotype, disease course, clinical stage, prevalence of cirrhosis and interferon therapy between autoantibody-positive and -negative subgroups.</p><p><b>CONCLUSION</b>Autoantibodies can be induced in the course of CHC, and some CHC patients can even develop autoimmune hepatitis.</p>