Abstract

Autoimmune thy roiditis ( hereinafter AIT) occurs in 3–5% of children. It usually develops during adolescence and is 4 to 8 times more common in girls. Autoimmune thyroiditis often coexists with other autoimmune diseases, such as type 1 diabetes or celiac disease. At the time of diagnosis, children with AIT are often euthyroid, but 30% develop hypothyroidism over the next 5 years. Autoimmune thyroiditis is often asymptomatic, but when hypothyroidism has developed, different nonspecific symptoms may occur. Goitre (enlargement of thyroid gland) occurs in twothirds of children with AIT. Hypothyroidism caused by AIT is rarely a reason for obesity but can be accompanied by weight gain. In children with longstanding hypothyroidism, the first symptom may be significant growth failure. Therefore, early detection and adequate treatment are important. In children with suspected AIT, levels of TSH, free T4, antiTPO and antiTG antibodies in serum should be measured. This paper examines a case of severe hypothyroidism caused by AIT in a 10year old girl.