Orbital Inflammatory Manifestations in a Patient With VEXAS (Vacuoles, E1 Enzyme, X-Linked, Autoinflammatory, Somatic) Syndrome.

Abstract: An 84-year-old man with a genetically confirmed diagnosis of VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome treated with tocilizumab reported with a 3-day history of left eye pain, conjunctival chemosis and injection, and horizontal binocular diplopia. Examination revealed restriction of left eye ductions in all directions with mild unilateral proptosis. MRI of his brain and orbits demonstrated abnormal enhancement of the left posterior sclera and intraorbital optic nerve sheath, without involvement of the extraocular muscles, cavernous sinus, or optic nerve parenchyma. B-scan ultrasonography heralded a positive "T-sign." Empiric treatment with high-dose intravenous methylprednisolone led to rapid clinical improvement. Workup for alternative causes was unremarkable. Oral prednisone dose and tocilizumab ultimately resulted in complete resolution after 4 weeks. The final diagnosis was consistent with orbital inflammatory manifestations of VEXAS syndrome.