Two of every thousand pregnancies are complicated by
Graves' disease. Diagnosis is suggested by maternal disorders (
tachycardia, exophthalmia,
weight loss.) or fetal disorders (
tachycardia, intra-uterine growth retardation,
preterm birth.). Due to transfer into the fetal compartment of maternal
antibodies which stimulate the fetal thyroid by binding to the thyroid
thyrotropin (
TSH) receptor, only 1% of children born to these mothers are described as having
hyperthyroidism. Neonatal
thyrotoxicosis disappears with clearance of the maternal
antibodies; clinical signs usually disappear during the first four Months of life. The most frequent neonatal clinical signs of
thyrotoxicosis are
tachycardia,
goiter, hyperexcitability, poor
weight gain, hepatosplenomegaly, stare and eyelid retraction. Diagnosis is based on determination of the blood level of
triiodothyronine (T3),
thyroxine (T4) and TSH. To confirm the nature of
hyperthyroidism,
thyroid-stimulating immunoglobulins (TSI) should be assayed. The kinetics of TSI provides a guide for therapeutic adaptation and disappearance of TSI is a sign of recovery. Rare cases of familial non-autoimmune
hyperthyroidism have been shown to be caused by germline mutation of the
thyrotropin receptor. We report a case of severe neonatal
hyperthyroidism which led to the diagnosis of maternal
Graves' disease.