Abstract #1402994: Unilateral Exophthalmos in A Patient with Hashitoxicosis: Case Report and Review of the Literature

Abstract

Hashitoxicosis is a transient period of hyperthyroid state in a patient with Hashimoto thyroiditis. Ii is not common condition. Exophthalmos is usually bilateral disease commonly associated with Graves's hyperthyroidism. It rarely occurs in Hashimoto thyroiditis or hashitoxicosis. Unilateral exophthalmos is a less common presentation of Graves's ophthalmopathy. So, we present this case of a male with Hashimoto thyroiditis, who presented with unilateral exophthalmos and Hashitoxicosis. A 41-year-old male presented with protrusion of his right eye. He was diagnosed 9 months ago with Hashimoto thyroiditis based on clinical ground, laboratory tests and thyroid scan. His TSH was 18.5 (N 0.4- 4) and FT4 was 0.023 (N12-22). TPO was positive (Thyroid Peroxidase anti-bodies). Thyroid scan showed diffused homogeneous reduced uptake. He was started on Thyroxine 100ug/day. Six months later his thyroid function test on follows up showed features of subclinical hyperthyroidism. His Thyroxine was reduced gradually till it was stopped. Three months later, he developed palpitations, weight loss and noticed changes in his right eye. On examination he was toxic his pulse 100 bpm, right eye there is exophthalmos, lid retraction and lid lag. He has small goiter and no bruit. No pretibial myxedema or proximal myopathy. Laboratory tests showed suppressed THS 0,013 and high FT4 26.8. We diagnosed him as having Hashitoxicosis and started on Propranolol 20 mg three times daily. He did not improve and repeated TSH was 0.006 and FT4 was 46.3(12-22). Neomercazole was started at a dose of 30 mg/day, Over the next 6 months Neomercazole was tapered until the patient become hypothyroid and thyroxine was restarted. Currently he is on thyroxine 100ug and is doing well. However, the exophthalmos did not resolve completely. Hashimoto thyroiditis is the most common cause of hypothyroidism in Iodine sufficient areas. It is characterized by elevated levels of thyroid anti-bodies (Anti TPO antibodies are present in 90% of cases). Hashitoxicosis is the hyperthyroid phase in chronic autoimmune thyroiditis. it occurs due to the release of preformed thyroid hormones from the inflamed thyroid gland. The exact duration of the disease is not well described, in average it last less than 8 months. The term Hshitoxicosis sometimes used to describe an autoimmune thyroid disease overlap syndrome of Graves's disease and Hashimoto disease. The presentation of our patient was consistent with Hashitoxicosis. But due to his severe symptoms and development of exophthalmos we suspect overlap syndrome, so we started antithyroid medication. Wasniewska et al. investigated the outcome of Hashitoxicosis in 14 children. Due to more severe presentation, four patients required antithyroid medications as in our patient. A definitive resolution of hyperthyroidism was recorded 8.3- 6.3 months after the diagnosis, as in our patient who recovered over a period of 6 months. Graves's orbitopathy (GO) usually associated with Graves's hyperthyroidism, rarely occurs in hypo- or euthyroid state, unlike our patient who developed unilateral exophthalmos in hypothyroidism.