Thyroid Dysfunction as Predictor of Sustained Virological Response (SVR) During HCV Treatment with PEGylated Interferon and Ribavirin

Background: Thyroid disease (TD) is the most common endocrine disorder associated with HCV infection, especially in conjunction with interferon-α (IFN-α)-based therapy. The aim of the work was to evaluate the role of thyroid dysfunction in HCV treated patients with combination therapy of interferon and ribavirin and correlate it with fibrosis stage. Materials and Methods: A retrospective study of 850 HCV genotype 4 Egyptian patients treated with combination therapy were studied. Their thyroid function was normal before the initiation of the treatment then 218 patients developed thyroid dysfunction after starting the treatment. Liver biopsy was done for all patients and they were divided into two groups; group I: early fibrosis and group II: significant fibrosis. Thyroid profile and sustained virological response (SVR) were assessed. Results: The SVR in HCV patients who did not develop thyroid dysfunction was 55.7% while it was 88.1% in patients who developed thyroid dysfunction during treatment. There were no significant differences between both groups in body mass index (BMI), gender, liver fibrosis, level of viremia (PCR) and SVR (PCR negative). Hypothyroidism was detected in 70.6 % and thyrotoxicosis in 29.4 %. The PCR negative patients were more in group II (92.3%) and 7.7% were PCR positive, while in group I the PCR negative patients were 84.2% and 15.8% were PCR positive. Conclusion: This study nurtures the necessity to carefully observe thyroid function in patients during and following completion of interferon treatment. Our findings suggest that thyroid dysfunction can be considered an important predictive value of SVR in HCV combination therapy.