Aims and objective: Pegylated interferon is widely used in the treatment of hepatitis C. Thyroid dysfunction (TD) is a well recognised side effect of interferon treatment. As the use of interferon therapy in hepatitis C is on the rise, we conducted an audit to determine its prevalence and to formulate local guidelines for the monitoring and management of thyroid dysfunction in these patients.
Methods: A case note based retrospective audit of all patients who received interferon treatment between 2007 and 2009 was done. Data on the monitoring of thyroid function in these patients was collected.
Results: Seventy-two patients completed interferon therapy during this period. Forty-seven patients (65%) had baseline thyroid function tests (TFT) and regular monitoring (at least 3 monthly) during the treatment period. A further 17 patients (24%) had TFT after completion of interferon treatment. Of the 61 patients with TFT monitoring, 8 (13%) developed TD (5 had transient hyperthyroidism, one subclinical hyperthyroidism, one hyperthyroidism followed by hypothyroidism and one hypothyroidism). There was female preponderance (62.5%) among patients who developed thyroid dysfunction. Hyperthyroidism developed at an average of 18 weeks after commencement of interferon.
Conclusion: The findings in this audit is similar to other studies regarding the incidence and female preponderance of thyroid dysfunction. Baseline TFT, TPO and TFT monitoring during and after IFN-based therapyi is important. TD in most cases is transient and a wait and watch policy should be adopted before instituting definitive therapy.