Endocrine Abstracts

JOINT4033

A 63-year-old non-smoker male was referred to the endocrinology clinic with symptoms of hyperthyroidism and abnormal thyroid function in November 2022. Initial tests confirmed Grave’s disease: TSH <0.03 mU/l (0.35-5.5), FT4: 60.7 pmol/l (10.5-21.0), FT3: >30.8 pmol/l (3.5-6.5), Thyroid Stimulating Immunoglobulins (TSI) 12.8 IU/l (<0.56). Impaired Liver function test (LFT) was noted: (ALT 71 U/L (10-49), ALP 145 U/l (30-130) and total bilirubin 8 umol/l (0-20). With a normal liver ultrasound, impairment was attributed to hyperthyroidism. The patient was commenced on carbimazole, but hepatic function deteriorated. A liver screen was negative, suggesting carbimazole-related hepatic impairment. Carbimazole was switched to propylthiouracil (PTU), but hepatic impairment persisted, leading to PTU cessation. Due to worsening thyroid function and reaction to antithyroid drugs, the patient was offered urgent total thyroidectomy, with preoperative preparation using Lugol’s Iodine. The patient underwent a successful total thyroidectomy in March 2023. Histopathology confirmed diffuse thyroid hyperplasia/Graves’ disease. 8 weeks postoperatively, symptoms of mild thyroid eye disease (TED) developed. TSI levels remained detectable at 2 and 3 months postoperatively (4.22 and 3.9 IU/l, respectively). An MRI at 4 months showed bilateral inferior rectus muscle enlargement, consistent with active thyroid ophthalmopathy. The patient was commenced on a 6-month course of selenium. At the 6-month ophthalmology follow-up, the patient had restricted upgaze and left lateral gaze, indicating ongoing TED. Visual function was intact. IV methylprednisolone (IVMP) was considered but not started. At the 10-month follow-up, ocular motility worsened. IVMP was initiated, with significant improvement after six infusions: reduced proptosis, resolution of lid retraction, and decreased upward gaze restriction. Some restrictions persisted, especially in the left upward gaze. Given the incomplete response to IVMP, he was considered for an additional IVMP course with orbital radiotherapy. Following combined therapy, TED became inactive, but diplopia and upward gaze restriction persisted. The strabismus team recommended a right superior oblique tuck or left inferior rectus recession. Monitoring continues whilst awaiting surgery. Graves’ ophthalmopathy is known to occur with other endocrine features of thyrotoxicosis, typically occurring within 18 months of the disease. The new development of Graves ophthalmopathy following thyroid surgery is rare. This case highlights a rare example of Graves’ ophthalmopathy developing following total thyroidectomy. Healthcare professionals must be aware of the possible late development of Graves’ ophthalmopathy following total thyroidectomy and refer for appropriate assessment without delay.