Thyroid and pancreatic islet cell antibodies in chronic hepatitis c [HCV] infection with and without diabetes

ABSTRACT

The prevalence and the clinical relevance of thyroid and pancreatic beta cell immunity in HCV +ve patients with and without diabetes before interferon [IFN-alpha] therapy remain controversial. So, the aim of the present study was 1-To determine the prevalence of organ specific Pancreatic beta cell and thyroid autoantibodies and organ non-specific antibodies [Anti Neutrophil Cytoplasmic Antibodies [ANCA], Anti Smooth Muscle Antibodies [ASMA] and Liver Kidney Microsomal Antibodies [LKMA] in HCV+ve patients with and without diabetes. 2- To evaluate whether autoimmune beta cell damage could be involved in the development of diabetes in HCV +ve patients. 3- To assess the clinical value and the relationship between such autoantibodies. Research design and Methods: The evidence of clinical autoimmune diseases and the presence of autoantibodies were assessed in 56 HCV+ve patients before INF-alpha therapy. Autoantibodies to Islet Cells [ICA], Thyroglobulin [TGAs]. Thyroid Peroxidase [TPAs] were tested by ELISA and immunometric assay, in addition to ANCA, ASMA and LKMA were tested by ELISA and immunoflorescence assay in 30 patients with diabetes [Group I], 26 patients without diabetes [Group II], in addition to 14 sex and age matched controls. Correlating these antibodies with age, sex, body mass index [BMI], presence of liver cirrhosis and its staging. It was found that age, BMI, family history of diabetes, and insulin levels were significantly higher in the diabetic group than in non diabetic HCV+ve patients. None of the 56 patients studied showed evidence of clinical autoimmune diseases. However, 5.4% of patients were positive for ICA[3/56], 10.7% [6/56] were positive for TGAs, 8.9% [5/56] were positive for TPAs. The coexistence of ICA and thyroid antibodies were found in only 3.6% of patients [2/56]. Furthermore, 71.4% of patients [40/56] were positive for ANCA, 35. 7% [20 /56] were positive for ASMA, 12.5% [7/56] were positive for LKMA. The frequencies of these autoantibodies were not significantly different in the presence- or absence of diabetes or when compared with controls except in ANCA +ve group in which antibodies were significantly higher [p<0.05] in the diabetic group. Moreover, ICA +ve patients were all diabetics. The ICA, TGAs and TPAs were more frequent among HCV+ ve female patients although most of our patients [75%,] were men. The presence of liver cirrhosis or / is staging according to Child Pugh score had no relation to the presence of such antibodies. Our study indicated a low prevalence of beta cell immunity and thyroid autoantibodies in HCV +ve patients. The level of such autoantibodies whether organ specific or non organ specific had no relation to the presence of diabetes or liver cirrhosis complicating or associated with HCV infection. Old age, high BMI, and family history of diabetes are risk factors for diabetes in HCV patients. Furthermore, the role of NCV in the development of diabetes was unlikely to be mediated by autoimmune mechanism. However, hyperinsulinemia and insulin resistance may play a role