Endemic goiter in the Jos Plateau region of northern Nigeria.

This study is an endemic goiter survey of 3476 school children in 13 Local Government Councils (LGCs) and 1004 subjects in a whole community of one LGC, Plateau State, Northern Nigeria, to determine the prevalence of goiter as well as to identify some of the etiological agents involved. Results of the survey showed that the disease is highly endemic in the area with prevalence varying in places from 1 to 23% of these subjects. Females showed a markedly higher prevalence of goiter. Analysis of 729 urine samples indicated that iodine excretion ranged from 3.5 to 1.3 microgram/dl (32-154 microgram/g creatinine) and was similar to that in iodine deficient areas in the world, but no relation was observed between the prevalence of goiter and urinary iodine. Urinary thiocyanate levels were less than 0.5 mg/dl, suggesting that the role of the thiocyanate as a goitrogen is not important in the region. Thyroid hormone parameters in village subjects with goiter were similar to those in goiter endemia except serum thyroxine (T4). An interesting result found in village subjects was very high serum thyroxine binding globulin, which leads to an increase in serum T4. This study indicated that Northern Nigeria is an area of endemic goiter. Although some areas in Plateau State are iodine deficient zones, we could not conclude that the etiology of endemic goiter in this area is associated with iodine deficiency. There may be an interplay of multiple factors of etiological importance.