A Rare Case of Dyshormonogenetic Fetal Goiter Responding to Intra-Amniotic Thyroxine Injections

摘要

Fetal goiter was detected by routine ultrasound in early pregnancy, gestational week (GW) 18, in a 28-year-old woman with no thyroid history, normal thyroid hormone levels and no TSH receptor or thyroid peroxidase antibodies. An umbilical cord blood sample was drawn in GW 23. The analysis indicated fetal hypothyroidism with TSH >100 mU/l(reference value 6.8 ± 2.9, mean ± SD), fT_4 3.8 pmol/l (reference value 16.5 ± 5.3, mean ± SD). Intra-amniotic injections of thyroxine were given in conjunction with ultrasound every 7-10 days, in total nine times during GW 24-33. A dose of TO ug thyroxine/kg of estimated fetal weight per day was administered on six occasions, and 5 mug/kg/day the last three times. Upon injections of thyroxine further growth of the goiter was reduced. Elevated amniotic TSH levels fell from 13 to 2.5 mU/l (reference range 0.04-0.51).Throughout pregnancy, fetal heart rate and skeletal maturation were within normal limits. In week 34, chorioamnionitis was suspected and the child was delivered by cesarean section.