Determination of thyroid volume by Sonography in healthy Brazilian schoolchildren.

PURPOSE: Our objective was to establish thyroid volume by sonography in Brazilian schoolchildren and to correlate thyroid volume with anthropometric characteristics.

METHODS

Sonographic studies of thyroid volume were conducted in 1,977 schoolchildren (6-14 years old) from 21 villages and towns in Central Brazil. Iodine concentration was analyzed in urine specimens and in salt samples obtained from the children's homes. Thyroid volumes were also compared with volumes reported for other countries.

RESULTS

Age, height, and weight correlated with thyroid volume. Thyroid volumes for boys and girls were generally lower than those obtained in Europe and comparable to those obtained in Malaysia and Iran. Urinary iodine excretion was considered elevated in about half of the Brazilian schoolchildren, and the iodine content of salt samples was more than 50 ppm in 58%.

CONCLUSIONS

We observed relatively smaller thyroid gland volumes in Brazilian schoolchildren as compared with those reported in Europe. This was apparently due to a higher iodine intake in our population.