BING NEEL SYNDROME: AN UNKNOWN GCA MIMICKER

Background: Giant cell arteritis (GCA) is a chronic granulomatous vasculitis of medium and large arteries leading to cranial and extracranial manifestations. Temporal artery biopsy is considered the gold standard; however, its sensitivity is low at 47%. We report a unique case of Bing Neel Syndrome (BNS) presenting as biopsy proven GCA. BNS is a rare complication (0.3-1%) of Waldenstrom Macroglobulinemia (WM), which results from the infiltration of lymphoplasmacytic cells (LPCs) and plasma cells into the central nervous system. Case presentation: 77-year-old female with a past medical history of glaucoma, hypertension, Diabetes and chronic ocular ischemic syndrome in her right eye presented with progressive left eye vision loss for 5 days. Fundoscopic examination was notable for pseudophakic pseudo pallor but no optic disc edema. Intraocular pressure was >40 and normalized after Diamox. The patient was started on pulse dose steroids by her neuro-ophthalmologist. She was discharged home on 60 mg of prednisone. At follow up with her neuro-ophthalmologist, new dot blot haemorrhages in the left eye were noted and she was readmitted for pulse dose of IV pulse methylprednisolone. Temporal artery biopsy was consistent with GCA spectrum. Work up revealed: kappa/lambda ratio of 7.58 (0.26-1.65). IgM 4000 paraprotein. Bone marrow biopsy demonstrated WM. Flow cytometry analysis of bone marrow aspirate detects 2% aberrant B cells that were positive for CD19, CD20, CD22, CD23, CD38 and CD45.. Surface light chain expression is kappa restricted. Flow cytometry was consistent with lymph histiocytic cell lineage. The patient was treated for her WM and her ophthalmic complications stabilized. Learning points for clinical practice: Histopathology has a key role in diagnosing GCA as its mediated by macrophages and T Lymphocytes. Immunohistochemical staining is helpful in such cases. Recurrence on high dose steroids in GCA points towards an alternate diagnosis. Figure 1. REFERENCES: NIL. Acknowledgements: NIL. Disclosure of Interests: None declared. DOI: 10.1136/annrheumdis-2024-eular.NA5 Keywords: Malignancy, Education Citation: , volume 83, supplement 1, year 2024, page 2Session: Case Reports: Case Report Sessions: Session 1 (Case Report Sessions: Session 1)

Malignancy, Education