Endocrine Abstracts

Introduction: Thyroid-associated orbitopathy is an autoimmune disease of the retroocular tissues commonly associated with Graves’ disease (GD) and rarely reported in Hashimoto’s thyroiditis (HT). GD and HT are autoimmune thyroid disease which are sometimes hard to distinguish from one another and their association in one person is rarely described. Here, we report a case of an exacerbation of thyroid-associated orbitopathy in a patient with GD following a SARS-CoV-2 infection and a phase of spontaneous hypothyroidism.

Case report: A 36-year-old smoker male was hospitalized in the endocrinology department for the management of a Graves’ orbitopathy. The diagnosis of GD was made two years ago in the presence of unilateral left orbitopathy, goiter, subclinical hyperthyroidism (TSH = 0.003 mUI/l and FT4 =1.36 ng/dl [0.9-1.7]) and positive anti-TSH receptor antibodies (TRAbs) = 5 IU/l (< 2 IU/l). Anti-thyroperoxidase (TPO-Ab) and anti-thyroglobulin (Tg-Ab) antibodies were negative. Thyroid scintigraphy showed intense homogenous hyper fixation of the gland. The patient received a small dose of antithyroid drugs. Euthyroidism was obtained after four months of treatment. After discontinuing medical treatment and follow-up for two years, the patient consulted for aggravation of his orbitopathy. He had a history of COVID-19 infection nine months ago and showed symptoms of hypothyroidism few months later. On examination, he had bilateral asymmetric orbitopathy without signs of activity. Laboratory exams confirmed hypothyroidism (TSH = 95 mUI/l and FT4 = 0.13 ng/dl). Antithyroid antibodies were positive: TPO-Ab = 291.4 IU/ml (< 60 IU/ml), Tg-Ab = 1055 IU/ml (< 100 IU/ml) and TRAbs = 2.37 IU/l.

Discussion: SARS-CoV-2 infection is associated with triggering of GD and HT. In our case, TPO-Ab and Tg-Ab were negative when the diagnosis of GD was first made. However, when the patient developed hypothyroidism, we found positive elevated levels of these antibodies and a concomitant decrease in TRAbs, suggesting a possible association between both diseases. Concerning the aggravation of the patient’s orbitopathy, it is most likely related to smoking and the spontaneous shift to hypothyroidism.