SUN-525 Successful Surgical Management of Graves’ Disease in Pregnancy

Background: Total thyroidectomy in pregnancy is not a widely used approach for management of Graves’ disease (GD) but is indicated when thyrotoxicosis persists in spite of efforts to optimise thyroid status. Clinical case: A 27-year-old lady with history of GD, presented at the 9(th) week of her second pregnancy. She had been counselled about anti-thyroid medications but was on carbimazole (CBZ) 30 mg tds and propranolol LA 80 mg od at presentation. She complained of palpitations, heat intolerance, irritability, weight loss and difficulty swallowing. On clinical examination, she had a heart rate of > 100/min and diffusely enlarged goiter with a bruit. Thyroid Ultrasound showed a right lobe of 6.5 x 2.8 x 2.7 cm and left lobe 5.3 x 2.6 x 2.4 cm. Free thyroxine (FT4) was 42.3 pmol/L (12–22), free triiodothyronine (FT3) 9.09 nmol/L (1.3–3.1), and TSH < 0.01 mIU/L (0.27–4.2). TRAB titer was >40 IU/L (0.0–1.75). She was advised to switch to propylthiouracil (PTU) and labetalol to minimize fetal adverse outcomes. She reported that she was unable to afford PTU and requested a switch back to CBZ. During her course of therapy, she had recurrent admissions with thyrotoxicosis, tachycardia, panic attacks and difficulty in swallowing. A decision was made to manage her with total thyroidectomy in the second trimester. She was treated with Lugol’s iodine, beta blockers and CBZ 2 weeks prior to her surgery and there were no immediate post-operative adverse events. Histology was consistent with GD. Her post-op TRAB titer remained >40 IU/L until present. She delivered at 28 weeks of gestation due to threatened premature labor a baby boy who had neonatal thyrotoxicosis, required admission to the neonatal ICU and therapy with flecanide and CBZ. His TSH was 0.09 mIU/L, (FT4) 68.7 pmol/L and TRAB 19.4 IU/L. He is currently 18 months old, well and not on any medications. Conclusion: Poor control of thyrotoxicosis is associated with pregnancy loss, prematurity, stillbirth, thyroid storm, and maternal congestive heart failure. Therefore, pre-pregnancy counseling is crucial to establish Euthyroid state for the safety of mother and fetus. Reference: (1) Davis LE, Lucas MJ, Hankins GD, Roark ML, Cunningham FG. Thyrotoxicosis complicating pregnancy. Am J Obstet Gynecol. 1989;160:63–70. doi: 10.1016/0002-9378(89)90088-4. (2) Vini L, Hyer S, Pratt B, et al. Management of differentiated thyroid cancer diagnosed during pregnancy. Eur J Endocrinol. 1999;140:404–406.