Endocrine Abstracts

JOINT2478

Introduction: Orbital myositis remains a rare condition that typically presents in an idiopathic acute form in young adult females. However, atypical forms related to specific autoimmune and inflammatory conditions are increasingly recognized. We report the case of a female patient with poorly controlled diabetes who developed acute orbital myositis with oculomotor nerve palsy.

Observation: A 50-year-old woman with 10 years of poorly controlled diabetes mellitus was referred to the Endocrinology department of IBN SINA university hospital in RABAT for further treatment of severe acidosis decompensation due to a medication discrepancy. During hospitalization, the patient developed sudden-onset ptosis associated by pain in the left orbit. Ophthalmological examination of the left eye revealed oculomotor paralysis, including divergent strabismus, diplopia, and mydriasis. An emergency cranio-orbital CT scan was performed and found to be normal. Magnetic resonance imaging (MRI) of the orbit showed homogeneous thickening of the right medial oculomotor and the levator palpebrae superioris muscles of the left eye, with no other associated abnormalities, suggesting myositis of probably inflammatory origin. Biological tests revealed a moderate inflammatory syndrome. Etiological work-up, including thyroid, immunological, and infectious tests, was negative. The diagnosis of orbital myositis in a patient with unbalanced diabetes was therefore established. The patient was started on oral corticosteroids (1 mg/kg/day) and referred to the ophthalmology department for further management.

Discussion and Conclusion: Diabetic oculomotor nerve palsy (ONP) is a complication of diabetes mellitus with distinct clinical sequelae that can affect a patient’s quality of life. Recent studies have confirmed that microvascular factors are responsible for nerve damage, leading to a loss of nerve function. Hyperglycemia causes microvascular alterations that reduce nerve perfusion and induce endoneurial hypoxia. Therefore, vasa nervorum dysfunction contributes to nerve ischemic injury during the development of diabetic neuropathy. Orbital myositis is a condition that most often occurs in middle-aged women. Its etiopathogenesis remains incompletely understood. The association with certain autoimmune diseases and small-vessel vasculitis suggests an immunological origin. Corticosteroid therapy remains the first-line treatment, with a good response, and an immunosuppressant can be added if necessary.

References: 1. Derbal, S., Rachdi, I., Zoubeidi, H., Daoud, F., Aydi, Z., Ben Dhaou, B., & Boussema, F. (2018). Myosites orbitaires: à propos de six cas. Revue Médicale de la Suisse, 14(451), 647-652. https://doi.org/10.1016/j.revmed.2018.03.217 2. Wang, H., & Ma, Y. (2023). Acupuncture treated oculomotor nerve palsy with diabetes mellitus: A case report. Explore: The Journal of Science & Healing, 2023. https://doi.org/10.1016/j.explore.2023.02.004