Endocrine Abstracts

Introduction: Although Graves’ orbitopathy (GO) is common in the course of Graves’ disease, dysthyroid optic neuropathy and corneal breakdown are rare. We describe two cases of severe GO treated successfully with rituximab.

Case 1: A 50-year-old female smoker with Graves’disease, presented with disfiguring eyelid edema, exophthalmos and diplopia, preserved visual acuity and clinical activity score (CAS) ≥ 5. She received pulsed medroxyprednisolone to a total of 6 gr and standard orbital radiotherapy 3 months later with minor improvement. Thyroid status stabilized on methimazole combined with lithium and an uncomplicated thyroidectomy followed. However, visual acuity declined to “hand motion”, necessitating two cycles of rituximab at 375 mg/m² each, two weeks apart. Lymphocyte depletion was immediate and sustained and visual acuity improved to 4/10 bilaterally. Three years later CAS=0 and the patient maintains a visual acuity of 2/10.

Case 2: A 78-year-old male non-smoker presented with hyperthyroidism initially thought to be due to toxic multinodular goiter and had thyroidectomy four months later. An incidental papillary thyroid carcinoma measuring 1.05 cm, insular type, was found at histology in the right lobe. He was referred for management of GO one month postoperatively, characterized by retrobulbar pain, chemosis and diplopia, CAS≥7, loss of color vision and visual acuity of 1/10 bilaterally. He received pulsed methylprednisolone to a cumulative dose of 8 g and orbital radiotherapy, resulting in mild improvement in inflammation, but worsening of the acuity to light perception on the right only, with relative afferent pupillary defect on the left and fixed globes. The patient then received two infusions of rituximab of 500 mg two weeks apart. He recovered vision to 2.5/10 in the right eye, which allowed his return to independent living. He subsequently received 100mCi ¹³¹I without GO relapse.

Conclusion: Rituximab therapy can benefit vision and quality of life in refractory, severe GO.