P013 A case report of posterior orbital inflammation associated with VEXAS(Vacuoles, E1 enzyme, X-linked, Autoinflammatory, Somatic) syndrome

Abstract

Abstract Background/Aims VEXAS (Vacuoles, E1 enzyme, X-linked, Autoinflammatory, Somatic) syndrome is a newly recognised adult-onset acquired autoinflammatory disease caused by somatic mutations of the UBA1 gene in the blood precursor cells. It is characterised by systemic inflammation and haematologic abnormalities. Methods Here we report a case of a 66 year old male who presented with orbital inflammation as one of the striking features of his underlying VEXAS. Results Our patient has a history of type 1 insulin dependent diabetes, otitis externa and recurrent lower limb distal venous thrombosis. He presented to Eye Emergency in May 2023 with rapid onset painful diplopia, left retrobulbar pain and peri-orbital swelling. He had recently been referred to Haematology with new anaemia and constitutional symptoms. MRI demonstrated inflammatory changes of some left extraocular muscles and cranial nerves. He was pulsed with three days of intravenous methylprednisolone with significant clinical response. Bone marrow biopsy reported reactive morphology and no clear myelodysplasia. In August 2023, the patient re-attended eye clinic with right sided facial swelling. Rheumatology were consulted for further opinion. The patient had previously been known to the department over 10 years ago, after presenting with arthritis labelled as diabetic cherioarthropathy. Extensive autoimmune panel was requested, including normal IgG subclass, weakly positive c-ANCA with a negative PR3. The patient had a new macrocytic anaemia (Hb 103 g/L, MCV 103 fl) and previous thrombocytopenia. Inflammatory markers were raised, CRP between 8-180, ESR 60 to 110 and Ferritin 878. Ultrasound of neck showed normal parotid and small reactive lymph nodes. Urgent PET-CT reported bone marrow reactivation with no significant findings. Prednisolone 40mg was given with marked resolution of the facial swelling. Opinion was sought by Haematology about any features of VEXAS on previous myelodysplasia screening. A week later, we received the result of the genetic testing showing a mutation of the UBAE gene, consistent with the diagnosis of VEXAS. The patient had re-occurrence of his inflammatory symptoms on several occasions [including diplopia, headache, rash, ocular pain, or periocular swelling] which were all steroid responsive. After discussion with multiple specialities, including Haematology, Ophthalmology and Immunology colleagues with a specialist interest in VEXAS, Tocilizumab was felt to be the most appropriate initial treatment. The patient is due for their first infusion in October 2023. Conclusion We report a unique case of VEXAS who presented with orbital inflammation, a less well-characterised feature of VEXAS. VEXAS is perhaps not as exceptionally rare as we first thought, it is likely more similar cases will present and we need to have a high degree of clinical suspicion in patients with unexplained systemic inflammation, especially those presenting initially with ocular inflammation. These patients require a multi-disciplinary approach to ensure best management of a very challenging condition. Disclosure C.A. Zollinger-Read: None. A. Zewar: None. L. Dunkley: None. J. Jefferis: None.