Thyroid diseases in a school population with thyromegaly.

A survey of 5462 schoolchildren was conducted for signs of thyroid disease in the seaside region of Sibenik, Croatia. In this region, salt is regularly iodised with 0.01% potassium iodide. Thyromegaly was found in 152 children (2.8%). The most common disorder was simple goitre, which was established in 126 of these, 12 boys and 114 girls (combined prevalence of 2.3%, and of 0.45% in boys and 4.07% in girls). Juvenile autoimmune thyroiditis was found in 19 of the children (prevalence 0.35%), with a female:male sex ratio of 8:1. Diagnosis was confirmed in all cases by fine needle biopsy. Thyroglobulin antibodies were detected in all 19 of the patients with juvenile autoimmune thyroiditis, but microsomal antibodies in only eight. Three patients had decreased concentrations of thyroxine and raised concentrations of thyroid stimulating hormone (TSH), one of these also with clinical hypothyroidism. Raised concentrations of TSH but with normal triiodothyronine and thyroxine were seen in two patients. Graves' disease was diagnosed in four children, three girls and one boy (combined 0.07%). Thyroid nodules were identified in three children (0.055%; two benign adenomas and one cyst). Only seven of the 152 patients with thyromegaly (three with hyperthyroidism and four with simple goitre) had previously sought medical advice, which points to the need for careful thyroid examination of apparently healthy children even in regions where the regular iodide intake is assumed to be sufficient.