LBMON134 Igg4 Related Hypophysitis And Skull Base Lesion: Retrospective Analysis Of 10 Years’ Experience Of A Tertiary Care Hospital Of Northern India.

INTRODUCTION: 'IgG4-related' disease is a spectrum of autoimmune phenomenon that clinically manifests with multisystem disorder in nearly 50% of the cases. The nervous system involvement is noted only in 4% of cases. Hypophysitis is considered as rare inflammation of the pituitary gland and/or stalk that results in pituitary enlargement, that may or may not be associated with hypopituitarism. Design and setting: Retrospective study from a tertiary care hospital of North India. METHODS AND PATIENTS: Biopsy proven IgG4-RD patients with various systemic manifestations registered in Postgraduate Institute of Medical Education and Research, Chandigarh between 2012 and 2022 were retrospectively analyzed. RESULTS: Among 3006 operated sellar and parasellar SOL since 2012, only 5 patients had IgG4 related hypophysitis and skull base lesion. After considering all organ systems, nearly 154 biopsy proven IgG4-RD had been reported from this institute. Three of those five patients were male and two were female. Mean age of presentation 32.2±9.49 years. Median duration of illness at presentation was 1 year. Two out of 5 cases reported with Headache, diminution of vision was the presenting complaints in rest of the three cases. Two of the 5 patients presented with some form of hypopituitarism. MRI showing Sellar space occupying lesion in 2 patients, although posterior pituitary bright-spot was absent in one case, none of them had diabetes insipidus at presentation. Three cases had stalk thickening on MRI. A female patient had retroperitoneal fibrosis leading to obstructive uropathy after four years of follow up of hypophysitis, one had associated craniopharyngioma, and one with testicular failure. Except one patient, all 3 patients had normal serum IgG4 level, data of one patient was missing. Methylprednisolone was the cornerstone of therapy for almost all the cases. DISCUSSION: Hypophysitis and inflammatory CNS lesions are not uncommon phenomena but relatively rare with IgG4-RD. IgG4-RD is diagnosed based on clinical and pathological criteria. The proposed diagnostic criteria include (1) characteristic diffuse or localized swelling or masses in single or multiple organs; (2) elevated serum IgG4 level; (3) histopathology demonstrating infiltration of lymphocytes and plasmacytes with the demonstration of IgG4 plasma cells (ratio of IgG4 to IgG cells > 40% and > 10 IgG4 plasma cells/high power field) and storiform fibrosis and /or obliterative phlebitis. The diagnosis is considered definite in the presence of all findings, probable if 1 and 3 are present, possible if 1 and 2 are present. Since they are inflammatory excellent steroid responsiveness has been documented in the literature. In this study we reported various presentation of hypophysial and skull base IgG4-RD which often confused as tumorous lesion, warrant high index of suspicion for diagnosis. Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.