Summary
Iodine deficiency, is the major cause of an increase in thyroid gland volume in infants
and children. In this field study we monitored the iodine supply and its effect on
the thyroid gland volume in prepubertal and pubertal children in the eastern and western
parts of the city of Berlin, so far considered as an area with borderline iodine deficiency.
The thyroid gland volume was determined by ultrasound in 1080 (f = 552, m = 528) children
aged 3–15 years, and was correlated to age, body-surface area and iodine excretion,
which was measured in a first-morning spot urine.
The mean iodine concentration was 115.8 μg iodine/g creatinine (12.2 μg iodine/dl
urine), with no significant differences between eastern parts with 114.5 μg iodine/
g creatinine (12.3 μg iodine/dl urine) vs 116.7 μg iodine/ g creatinine (12.0 μg iodine/dl
urine) in the western parts of the city. This good iodine supply of the children was
surprising compared to former studies in children and adults. Moreover this normalization
of the iodine excretion was reflected by smaller thyroid gland volumes in the children.
The volume was found to increase with age and was 2.4 ± 1.1 ml in prepubertal (Prader
and Largo: f ≤ 10.9 ys, m ≤ 11.5 ys) children, compared to 4.3 ± 1,7 ml in pubertal
children. The goiter prevalence, calculated on this data was below 5% . Among all
children there were only 11 (aged 8–13 ys) with abnormal findings of the thyroid gland
on ultrasound: 6 with small nodules, 1 girl with a thyroid-cyst, 2 girls had an inhomogenous
echo structure and 2 girls presented with a hemithyroidea. This study shows that the
iodine supply of the children in Berlin has improved, resulting in smaller sized thyroid
glands, compared to those which have been previously published for Germany (Müller-Leisse
1988; Klingmüller, 1991; Menken, 1992), but they correspond well to volumes described
in countries with sufficient iodine supply.
Key words
Urinary iodine excretion - iodine prophylaxis - endemic goiter - thyroid volume in
children - ultrasound
