Background: Exophthalmos, myxedema, and osteoarthropathy syndrome is a very rare condition that is associated with Graves' disease. The presence of dermopathy and the involvement of joint/bone tissues indicate that it seems to be related with the severity of the autoimmune process. Owing to its low incidence, there is a lack of information regarding its treatment and clinical follow-up. Some cases improved after use of high doses of steroids; however, some patients do not respond to this treatment. Recently, the effectiveness of rituximab for treatment of Graves' ophthalmopathy resistant to corticosteroids has been demonstrated. However, it has never been used for the treatment of exophthalmos, myxedema, and osteoarthropathy syndrome (particularly for the treatment of osteoarticular manifestations).
Case presentation: We present the case of a 54-year-old Mexican woman previously treated for Graves' disease who developed post-iodine hypothyroidism and exophthalmos, myxedema, and osteoarthropathy that did not improve after high doses of steroids (intravenous and oral). Her exophthalmos, myxedema, and osteoarthropathy syndrome symptoms improved as early as 6 months after treatment with rituximab.
Conclusion: Exophthalmos, myxedema, and osteoarthropathy syndrome is a non-classical presentation of Graves' disease, whose clinical manifestations could improve after treatment with rituximab, particularly in those patients with lack of response to high doses of corticosteroids.
Keywords: Exophthalmos; Myxedema; Primary hyperthyroidism; Rituximab.