SAT-580 Tocilizumab Improvement in a Patient with Corticosteroid Resistant Thyroid Orbitopathy: Report of a Case

Thyroid orbithopathy is an autoimmune disorder being the most frequent extrathyroideal manifestation. It can present before or even years after hyperthyroidism, although occasionally in nonhyperthyroid patients. The severe form has been described in 5% of the presentations. Treatment begins with smoking cessation, and maintenance of euthyroidism. The active forms are treated with systemic glucocorticoids however there is a 20% of nonresponder. Tocilizumab has been effectively used in corticosteroid resistant ophthalmopathy. There are reports of other treatments used such as rituximab with conflicting results which is why we decided to use tocilizumab. 1,2. We present two cases: a 59 year old woman with ophthalmopathy and hyperthyroidism treated since 2017 with tocilizumab. At the moment of receiving the medication they were euthyroid with severe orbitopathy measured by a clinical activity score of 6 refractory to systemic steroid treatment with previous use of six grams without disease control. We considered biological therapy after surgical decompression with tocilizumab at a dose of 8 mg per kilogram every four weeks during four months. The patient changed from a CAS of 6 to a CAS of 1 having an associated improvement in quality of life. A second woman of 55 years was started after receiving 6 grams of methylprednisolone without any improvement of the CAS. She started with a CAS of 6 and is currently at 3 with the third dose of tocilizumab.Tocilizumab is a humanized monoclonal immunoglobulin G1 antibody to the interleukin 6 receptor that has been used in rheumatoid arthritis. The pathophysiology starts with autoreactive B cells that recognize de TSH receptor as an autoantigen and secrete interleukin 6 amongst others that stimulate fibroblasts with the rest of the cascade. A reduction of proptosis with a mean of 3.92mm, 83% showed improvement in visual motility, 53.8% had resolution of diplopia, improvement of CAS up to 27 months without severe adverse effects reported. Some type of improvement has been reported in some series in 100% of patients. 2 Bibliography Stan, M; Garity, J; Carranza, B; et all. Randomized Controlled Trial of Rituximab in Patients With Graves Orbitopathy. J Clin Endocrinol Metab 100(2015): 432-411. Perez, J; Alvarez, A; Gomez E. Treatment of active corticosteroid resistant graves orbitophaty. Ophthalmic Plast Reconstr Surg 2014;30:162-167. Wiersinga, W. Advances in treatment of active, moderate to severe graves ophthlamopathy. Lanced Diabetes and Endocrinol 2016:1-9. Russel, D; Wagner, L; Seiff, S. Toxiclizumab as a steroid sparing agent for the treatment of Graves orbitopathy. American Journal of Ophthlamology Case Reports 7(2017)146-148.