Endocrine Abstracts

Background: Delayed new-onset Graves’ orbitopathy (GO) or worsening of existing GO occurs in approximately 15–20% of patients following radioiodine treatment (RAI), mostly within 12 month.

Case Report: A 57-years-old woman was referred in April 2016 to our endocrinology department for Graves’ disease hyperthyroidism. Relevant medical history included chronic lymphocytic leukemia (2004), fludarabine-related interstitial pneumonia with temporary tracheotomy (2009) and cytomegalovirus pneumonia secondary to rituximab (2013). Disease was in remission since 2013, requiring monthly intravenous immunoglobulins. The patient was ancient smoker (stopped 2008). At presentation, there were no symptoms of GO, TSH was undetectable, T4 58 ng/l (10–16), T3 25.4 ng/l (2–4.4), TRAbs 18.1 U/l (<1.5). Propylthiouracil (PTU) and betablockers were introduced. Six days after introduction of PTU 200mg/day, agranulocytosis and meningitis developed. After clinical stabilization of infectious disease, RAI (500MBq) was administered. Simultaneously, prednisolone (0.5 mg/kg) was introduced and gradually decreased over 4 weeks. Two months post-RAI, hypothyroidism occurred (TSH 38 mU/L, T3 1.37 pmol/l (3.1–6.8), T4 6.4 pmol/l (12–22)) despite the introduction of 50 μg thyroxine. The supplementation was increased to 100 μg to achieve euthyroidism. The evolution was eventless until February 2018 (22 months), when she presented to the ophthalmology department with a sudden orbital swelling and redness, prevailing in the right eye associated with multidirectional diplopia. Visual acuity was 10/10 bilaterally, there was a minimal proptosis, (18 mm right eye and 17 mm left eye), NOSPECS score at 4, Clinical Activity score (CAS) at 3/7. Orbital magnetic resonance imaging (MRI) showed extraocular muscle edema with a bright signal from the lateral and inferior recti muscles at gadolinium-enhanced image consistent with GO and mild right proptosis. TSH was 7.75 mU/l (vs 2.5 mU/l, December 2017), T4 11.9 ng/l (10–16), T3 2.4 ng/l (2–4.4) TRAbs: 10.4 U/l (VN<1.5). High-dose systemic methylprednisolone was administrated, cumulative dose 3.5 g (6 weekly 0.5 g infusions, then 2 weekly 0.25 g infusions). Topical lubricants and selenium supplementation were introduced. Clinical control after 6 weeks showed CAS 2/7 with persistent vertical diplopia, with no significant improvement at MRI. Patient refused radiotherapy. CAS was 3/7 at 3 months, 2/7 at 6 months. Ocular motility improved and conjunctival chemosis decreased. At 9 months patient showed no activity signs. All clinical symptoms resolved, except for a small bilateral lid retraction. TSH was 0.45 UI/l, surprisingly TRAbs were 34.4 U/l (<1.75). 12-month clinical assessment remained unchanged.

Conclusion: De novo orbitopathy may occur several months after radioiodine treatment in Grave’s disease despite glucocorticoid prophylaxis. Close monitoring and screening for orbitopathy can lead to early treatment and improved long-term eye prognosis.