Urinary iodine and other iodine deficiency indicators in a sample of school-age children in Egypt.

Sufficient data relating urinary iodine excretion in children to other iodine deficiency indicators are lacking in Egypt. We assayed urinary iodine concentration and serum levels of thyroid stimulating hormone (TSH), thyroglobulin, free triiodothyronine (T3) and free tetraiodothyronine in 99 school-aged Egyptian children. Goitre was found in 25 children. Median urinary iodine concentration was 70 microg/L. We found mild iodine deficiency (50-99 microg/L) in 60.6 % of the children and moderate to severe deficiency (< 50 microg/L) in 31.3%. The latter showed a high frequency of goitre and elevated mean serum free T3, TSH and thyroglobulin levels. Individual urinary iodine excretion rates vary, therefore these other indicators could help in screening for iodine deficiency at an individual level, especially in moderate to severe deficiency.