[Thyroid dysfunctions in children with chronic hepatitis C during interferon alpha-2b therapy].

Thyroid dysfunctions are the most frequently described extrahepatic syndromes which complicate HCV infection. Application of interferon in the treatment of chronic hepatitis C increases the frequency their occurrence. The aim of this study was analysis of the frequency of thyroid dysfunctions in children with chronic hepatitis C treated with recombined and pegylated interferon alpha-2b. The study was comprised of 50 children (19 girls, 31 boys) aged from 4 years to 18 years (average 14 years and 6 months) with chronic hepatitis C. Thirty children were treated with recombined interferon alpha-2b and ribavirin, while twenty children received the pegylated interferon alpha-2b and ribavirin. In all children the concentration of thyroid hormones: TSH, fT3 and fT4; as well as the concentration of thyroid antibodies: anty-TG and anty-TPO were examined before beginning of treatment and immediately on its completion. The control group was comprised of 25 children (13 girls, 12 boys) aged from 5 years to 18 years (average 13 years and 6 months) with no observed diseases of liver or thyroid gland. The conducted examinations did not reveal any significant difference in frequency of abnormal concentration occurrence of TSH and fT4 in children with chronic hepatitis C in relation to the control group (respectively: 34% and 20%). However, an abnormal concentration of fT3 was more frequently observed in children infected with HCV, but the average values of this hormone concentration did not significantly differ in both analysed groups of children (respectively: 3.8112 pg/ml and 3.8012 pg/ml). The combined treatment of interferon alpha and ribavirin did not influence more frequent occurrences of abnormal thyroid hormone concentrations, in comparison to their values before treatment. Clinical symptoms of thyroid dysfunction did not accompany the incorrect concentrations of thyroid hormones. Before the treatment, incresed concentration of antithyroid antibodies was observed in a similar percentage of the HCV infected children, as of the healthy children (respectively: 8 and 12%). However, in the group treated with ribavirin and interferon alpha, and especially its pegylated form, the increased concentration of antithyroid antibodies was frequently observed (32% children). The abnormal values of antithyroid antibodies appeared more frequently in girls (10/16). The conducted examinations showed frequent appearance of abnormal values of thyroid hormones and antithyroid antibodies, which indicates the necessity of a systematic control of thyroid gland function in children with chronic hepatitis C treated with interferonem alpha.