The natural course of Hashimoto's thyroiditis in children and adolescents.

Abstract

Hashimoto's thyroiditis (HT) is the most common cause of thyroid disease in children and adolescents, but little is known about the long-term follow-up of HT. The aim of this study was to analyze the clinical and laboratory characteristics and to observe the natural course of HT in children and adolescents. We retrospectively reviewed 153 patients with HT diagnosed before 18 years of age. Subjects were grouped into euthyroid, subclinical hypothyroidism, overt hypothyroidism, and hyperthyroidism on the basis of the thyroid function test. Of the 153 subjects, 133 were followed up (range 6∼181 months) at our clinic every 6 months for evaluation of goiter size, thyroid function, thyroid peroxidase antibodies (TPO Ab), and thyroglobulin antibodies (TG Ab) serum concentration. Thyroid function tests at the time of presentation revealed euthyroid in 72 patients (47.1%), subclinical hypothyroidism in 48 (31.4%), overt hypothyroidism in 22 (14.4%), and hyperthyroidism in 11 (7.2%). Serum TPO Ab and TG Ab significantly decreased in the subclinical hypothyroidism group with levothyroxine treatment. Also, there was a significant decrease in the mean serum TG Ab levels among the overt hypothyroid patients during the follow-up period, although TPO Ab levels were not significantly different when compared to their baseline TPO Ab levels. Most children with HT were euthryoid and remained euthyroid during follow-up. However, thyroid function should still be monitored periodically for early detection and treatment of overt hypothyroidism. Our data also showed that levothyroxine treatment may have beneficial effects on the thyroid antibody titers.