[Congenital hypothyroidism in Iceland 1979-1993.].
A nationwide screening for congenital hypothyroidism (CHT) was initiated in Iceland on January 1st 1979. From the beginning the screening consisted of TSH measurements from blood samples obtained on the fifth day of life on filter paper. TSH was initially assayed by RIA but since 1990 DELFIA fluoroimmunoassay has been used. During the 15 year period 1979-1993, a total of 65,892 children were born in Iceland. Participation in the screening program was 99.5%. The diagnosis of CHT was established in 21 cases, eight boys and 13 girls or 1/3138. Elevated TSH was found in 33 infants in the initial screening program, but on recall, thyroid function proved to be normal in 12 infants. Two infants had transient hypothyroidism presumably caused by TSH blocking antibodies of maternal origin. In one infant CHT was diagnosed on the first day of life because of a large goiter. Goiter was found in six infants on diagnosis, ectopia in six and no uptake on thyroid scan in three infants. In six infants thvroid scan was not performed. The diagnosis was delayed for 71 and 131 days respectively in two infants. Both infants had severe neonatal problems needing intensive care. On follow-up, those two children have a mild developmental delay. In the remaining 19 children mental development has been normal as judged by school performance and developmental tests. Growth has been within normal limits in all cases, mean SDS for height is 0.3. The incidence of CHT in Iceland is comparable to the results published recently in most of the other Nordic countries.
Thorsson
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Gudmundsson
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