Abstract
Serum thyroid-stimulating hormone (TSH) , thyronine (T4) and triiodothynine (T3) levels were measured in 23 children (9 boys and 14 girls) and 18 adults (9 males and 9 females) with goitre from an endemic goitre region of the Sudan. Similar studies were made in 2 girls, 6 women, 2 boys and 6 men who lived in the same region but showed no evidence of goitre. Serum was also obtained from 26 "control" subjects from Khartoum. Low serum T4 levels were found in the majority of the goitrous subjects. Statistical analysis revealed highly significant differences in T4 between the control subjects and both the goitrous and non-goitrous subjects from the endemic area. Elevated or high normal T3 levels were found in the great majority of the goitrous subjects and in a proportion of the non-goitrous subjects from the endemic region, and also in 7 of 26 from Khartoum. There was a
statistically significant difference in T3 levels between the controls and the goitrous subjects but not between the controls and the non-goitrous subjects from the endemic region. T3/T4 ratio differed significantly between the controls and the goitrous subjects, and also between the controls and the non-goitrous subjects from the endemic region. Raised TSH levels were found in the majority of the goitrous subjects (in 20 of the 23 goitrous children) in only 2 of the non-goitrous subjects from the endemic area, but in none of the control subjects. The iodine, calcium and fluoride contents of the water from one village in the endemic region were measured. The implications of these results is discussed with particular reference to the metabolic advantages of preferential secretion of T3 in states of thyroid stress.