Central Congenital Hypothyroidism in A Preterm Infant Born to A Mother with Graves’ Disease: A Case Report

Background: Central congenital hypothyroidism (CCH) is an uncommon but potentially underdiagnosed condition, particularly in infants born to mothers with autoimmune thyroid disease. Case Presentation: We report a case of central congenital hypothyroidism in a preterm baby born to a mother with hyperthyroidism, diagnosed three years prior to conception. She developed thyrotoxicosis at 30 weeks of pregnancy requiring Lugol’s iodine, carbimazole and propranolol. She subsequently developed pre-eclampsia and went into preterm Labour at 31 weeks of gestation. Her Thyroid Stimulating Hormone (TSH) receptor antibody levels were high, while anti-peroxidase and anti-thyroglobulin antibodies were negative. The cord TSH level at birth was very low. Subsequently, regular thyroid function tests continued to show very low TSH with normal Thyroxine (T4) levels. At one month of life, the child was started on Levothyroxine. TSH receptor antibodies were positive. He was noted to have constipation and an umbilical hernia during this review. The diagnosis of CCH was made. After initiation of therapy, T4 levels have normalized. Discussion / Conclusion: CCH is a rare condition, and the risk is significantly increased in infants born to mothers with Grave’s disease. In Grave’s disease, patients may have TSH-blocking antibodies that bind to TSH receptors but do not initiate intracellular signaling, resulting in hypothyroidism. This case highlights the importance of monitoring T4 and TSH levels in infants born to women with Grave’s disease.