Endocrine Abstracts

Introduction: Hyperthyroidism during pregnancy is a rare condition and occurs in 0.1–0.4% of all pregnancies. Graves’ Disease and transient gestational thyrotoxicosis constitute the majority of emerging thyrotoxicosis during pregnancy. Subacute thyroiditis (SAT) may also cause temporary hyperthyroidism.

Case report: A thirty-three-year-old, 13-week pregnant patients was admitted with fatigue, pain and swelling in thyroid lodge. Thyroid function tests performed two months ago were found to be in the normal range. On physical examination of the patient, there was no symptoms other than pain in the neck, and bilateral thyroid gland was large with tenderness. In the laboratory tests carried out at the patient’s admission, TSH was: 0.17 (0.4–4.2) μı/ ml, fT4: 2.67 (0.65–1.7) ng/dl, fT3: 4.58 (2.5–3.9) pg/ml C-reactive protein (CRP): 5.27 (0–0.8) mg/dl, erythrocyte sedimentation rate (ESR): 41 mm/h, anti-thyroid peroxidase (anti-TPO): 3.54 (1–16) IU/ml, thyroid receptor antibody (TRAb): 3.88 (0–14) U/l, anti-thyroglobulin (anti-TG): 1715 (5–100) IU/ml, WBC: 9800 μl In the thyroid USG both lobes were large and parenchymal blood flow was not increased. There was a distinct view of bilateral subacute thyroiditis and reactive bilateral cervical lymphadenopathy. Paracetamol 3×500 mg was started because of the pain. The patient’s pain was significantly decreased 3 days later. Clinical and laboratory findings in patient was compatible with SAT. 10 days later, pain and tenderness in the thyroid lodge was completely relieved. After repeated laboratory tests, 50 mcg of levothyroxine was instituted. With levothyroxine treatment, patient did not experience any problem during pregnancy and when she was 38 weeks and 2 days pregnant, vaginally delivered a healthy baby boy who weighs 3740 gr.

Conclusion: When determining the differential diagnosis of thyrotoxicosis in pregnancy, subacute thyroiditis should also be considered and detailed history and physical examination of the thyroid should not be neglected.