Thyroid volumes and iodine status in Egyptian South Sinai schoolchildren

The determination of goitre prevalence in children by ultrasonography is an important tool for considering iodine deficiency disorders. Our objective was to describe measurements of thyroid volumes by ultrasonography in Egyptian South Sinai schoolchildren and compare these with the WHO/International Council for the Control of Iodine Deficiency Disorders normative thyroid volume criteria (WHO/ICCIDD).

Cross-sectional thyroid ultrasonographic data of 719 schoolchildren (339 boys and 380 girls), aged 6-12 years from five cities in South Sinai (El Tur (T), Abu Redis (R), Ras Sudr (S), Saint Katherine (SK), and Nwebaa (N)). Age/sex and body surface area/sex specific upper limits (97(th) percentile) of normal thyroid volume were derived and urinary iodine (UI) was measured.

The median value of urinary iodine was 150 µg/l. Comparing WHO/ICCIDD thyroid volume references to Egyptian South Sinai schoolchildren resulted in goitre prevalence of 10.6% using age/sex specific and 13.48% using body surface area/sex specific cut-off values. The prevalence of goitre was 20.0% in S, 16.3% in R, 10.8% in N, 9.9% in T, and 10.5% in SC. Upper limits of normal (97(th) percentile) thyroid volume from South Sinai schoolchildren calculated using BSA, sex, and age were higher than the corresponding WHO/ICCIDD.

Prevalence of goitre is high in South Sinai schoolchildren. The body surface area reference should be preferred to the reference based on age. South Sinai schoolchildren had larger thyroids than WHO/ICCIDD thyroid volumes, perhaps due to hard polluted water with a high fluorine level.