[Clinical features of antiviral therapy-induced thyroid disease in patients with chronic hepatitis C].

OBJECTIVE

To investigate the clinical features of thyroid disease occurring in response to antiviral therapy in patients with chronic hepatitis C (CHC).

METHODS

Eighty-two patients diagnosed with CHC were recruited for study from our hospital between 2009 and 2010. All patients were given a 48-week course of antiviral combination therapy with pegylated-interferon (Peg-IFN; 180 mug qw ih) and ribavirin (RBV; 15 mg/kg bw). Patient sera was collected prior to treatment (baseline), at treatment weeks 24 and 48, and post-treatment week 24, and used to detect changes in levels of thyroid function markers, thyroid-specific and other autoantibodies, complement factors, and immunoglobulins (Igs). Differential expression of biomarkers was assessed between patients who developed thyroid disorder and those who did not.

RESULTS

At treatment week 48, 13.4% (11/82) of cases developed hypothyroidism, 3.7% (3/82) developed hyperthyroidism, 20.7% (17/82) tested positive for thyroglobulin antibody, and 22.0% (18/82) tested positive for thyroid peroxidase antibody. The patients who did not develop thyroid disease had significantly higher post-treatment levels (vs. baseline) of IgG (14.84 +/- 2.61 vs. 12.95 +/- 3.32 g/L, F = 10.458, P = 0.002) and C4 (0.26 +/- 0.09 vs. 0.22 +/- 0.08 g/L, F = 6.835, P = 0.011) and significantly lower IgM (0.86 +/- 0.48 vs. 1.00 +/- 0.42 g/L, F = 9.106, P = 0.003). The patients who developed thyroid disease showed no significant differences in the baseline and post-treatment levels of IgG, C4, or IgM. When the two groups of patients who did or did not develop thyroid disease were compared, there was no difference in the amount of patients who achieved sustained virological response.

CONCLUSION

Antiviral-induced thyroid disease in patients with refractory hepatitis C manifests as clinically-detectable abnormalities in serum levels of thyroid autoantibody and markers of hypothyroidism. Levels of other autoantibodies and Igs do not correlate with the development of thyroid disease in these patients, and thyroid disease does not appear to affect the efficacy of Peg-IFN + RBV antiviral therapy.