Endocrine Abstracts

Introduction: Graves orbitopathy (GO) is an inflammatory condition of the orbital fat and muscles and affect 30-50% of patients with Graves’ disease. The first-line treatment of moderate to severe GO according to EUGOGO is intravenous glucocorticoids, but 20-30% of the cases appear to be corticosteroid resistant or refractory. Promising results have been described with Tocilizumab (TCZ) as a second-line moderate to severe GO treatment.

Case presentation: We report a case of a 33-year-old female presented in our hospital with severe bilateral proptosis and spontaneous retrobulbar pain, lower eyelid retraction, periorbital edema, chemosis without diplopia. She was a former smoker, diagnosed with GO one year before and treated with intravenous methylprednisolone (cumulative dose 4.5gr) with only partial response. After glucocorticoid cessation, the disease relapsed with clinical signs of dysthyroid optic neuropathy and the patient underwent orbital radiotherapy (20Gy). At presentation patient was in thyrotoxic state with TSH=<0.008μIU/ml (n.v.: 0.27-4.2), T3=7.2 nmol/l (n.v.: 0.9-2.8), T4=265 nmol/l (n.v.: 58-140) and markedly increased TSI=19.30 IU/l (n.v <1.75). She was treated with methimazole. CAS score was calculated at 5/7, and protrusion was measured with Hertel exophthalmometer at 30 mm for the right and 31 mm for the left eye, respectively. Upon ophthalmologic evaluation, she was diagnosed with severe keratopathy due to cornel exposure. Orbital MRI was performed, which revealed inflammation of all orbital muscles, predominantly the inferior, medial and lateral rectus binocular. Due to the severity and the progression of the disease despite the corticosteroid treatment and radiotherapy, the patient initiates therapy with TCZ (RoActemra), a monoclonal antibody that inhibits the IL-6 receptor. She received 4 intravenous doses (8 mg/kg) every 28 days, according to Perez-Moreiras RCT. On follow up, symptoms were improved impressively, and CAS score regressed to 1/7. On exophthalmometry, proptosis was 21 for the right, 22 for the left eye, and TSI were within normal values. Moreover, a significant radiological improvement on MRI was established, with decreased size of all affected muscles.

Conclsion: We present this case to raise awareness for the effectiveness of the IL-6 receptor inhibitor (Tocilizumab), to the management of moderate to severe, corticosteroid resistant or refractory GO, of recent-onset, with lower cost compared to other novel therapies such as teprotumumab.