Fetal/Neonatal Thyrotoxicosis in a Newborn From a Hypothyroid Woman With Hashimoto Thyroiditis.
Fetal/neonatal thyrotoxicosis is a rare but potentially life-threatening condition. It is most commonly observed in poorly controlled Graves disease during pregnancy.



Here we describe a fetus/newborn patient with thyrotoxicosis who was born of a woman with Hashimoto thyroiditis and levothyroxine-treated hypothyroidism. Transplacental passage of stimulating thyrotropin (TSH) receptor antibodies, which were measured by a cell-based bioassay, was the underlying mechanism of fetal/neonatal thyrotoxicosis, although the mother had no history of hyperthyroidism.



Diagnosis and management of fetal hyperthyroidism can be challenging. TSH receptor antibody testing should be considered in pregnant women with any history of autoimmune thyroid disease and symptoms of fetal hyperthyroidism.
Clinical Division of Endocrinology and Metabolism, Department of Medicine III.
Florian W
FW
Kiefer
Division of Neonatology, Pediatric Intensive Care and Neuropediatrics, Department of Pediatrics.
Katrin
K
Klebermass-Schrehof
Division of Neonatology, Pediatric Intensive Care and Neuropediatrics, Department of Pediatrics.
Manuel
M
Steiner
Department of Obstetrics and Gynecology.
Christof
C
Worda
Division of Neuroradiology and Musculoskeletal Radiology, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, A-1090 Vienna, Austria; and.
Gregor
G
Kasprian
Molecular Thyroid Research Laboratory, Johannes Gutenberg University Medical Center, 55131 Mainz, Germany.
Tanja
T
Diana
Molecular Thyroid Research Laboratory, Johannes Gutenberg University Medical Center, 55131 Mainz, Germany.
George J
GJ
Kahaly
Clinical Division of Endocrinology and Metabolism, Department of Medicine III.
Alois
A
Gessl
D000328:Adult; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis* / Q000188:drug therapy / Q000209:etiology; D050031:Hashimoto Disease / Q000503:physiopathology*; D006801:Humans; D007037:Hypothyroidism / Q000150:complications*; D018828:Immunoglobulins, Thyroid-Stimulating / Q000097:blood*; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000175:diagnosis* / Q000188:drug therapy / Q000209:etiology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000175:diagnosis* / Q000188:drug therapy / Q000209:etiology; D011379:Prognosis; D013971:Thyrotoxicosis / Q000175:diagnosis* / Q000188:drug therapy / Q000209:etiology
D018828:Immunoglobulins, Thyroid-Stimulating; C094372:thyrotropin-binding inhibitory immunoglobulin