RESUMO
Hypothyroidism is a frequent glandular dysfunction, easy to be diagnosed by measuring the thyroid-Stimulating Hormone [TSH] level. One of its different causes is the abnormal migration of thyroid cells during the embryogenesis. This article reports a case of a four weeks newborn child presenting clinically by apparent hypothyroidism and a deficiency of thyroid hormones. The cervical palpation does not find the thyroid gland. The thyroid scintigraphy by the iodine 123 shows a median uptake between the normal place of thyroid gland and the tongue base. Furthermore, there is no uptake at thyroid position. A substitute treatment was quickly established to avoid the irreversible cerebral damage. The ectopic thyroid is an important etiology of the congenital hypothyroidism. The thyroid scintigraphy is an interesting functional exam because the cervical ultrasonography is difficult to be realized for a newborn child and, it does not show highly situated ectopic cells. All these aims at appreciating the prognosis and reassuring the parents