Sightless in subtypes: a rare case of igg-4-related hypophysitis

SESSION TITLE: Critical Care Case Report Posters 40 SESSION TYPE: Case Report Posters PRESENTED ON: 10/10/2023 09:40 am - 10:25 am INTRODUCTION: Lymphocytic hypophysitis (LH) is a rare inflammatory condition characterized by plasma cell infiltration of the pituitary gland. It is more commonly seen in females and often associated with pregnancy. The characteristic presentation includes headache, diabetes insipidus, and hypopituitarism. In suprasellar/para-sellar extension, mass effect can present with visual loss. Corticosteroids are the mainstay of therapy in these situations and usually are very effective, with surgery reserved for larger compressive masses with threatened vital structures (1). Medical therapy is aimed at improving inflammation and treating endocrinopathies. Here we present a case of a young female who presented with vision loss secondary to a pituitary mass compressing the optic chiasm, who underwent transsphenoidal biopsy and decompression with resulting histologic confirmation of IgG-4 positive lymphocytic hypophysitis. CASE PRESENTATION: A 31-year-old postpartum female presented with progressive severe headaches, dense bitemporal hemianopsia, and diabetes insipidus. These symptoms developed during pregnancy, about two months prior, with rapid progression to near blindness. Labs were significant for pan-hypopituitarism. An MRI performed revealed a large sellar/suprasellar lesion exerting significant mass effect on the optic chiasm (2.4 cm x 2.6 cm). Neurosurgery planned for transsphenoidal biopsy and decompression of pituitary mass. Intraoperatively they encountered a firm and fibrous mass, unlike any typical pituitary tumor, therefore the entire mass was not removed. Histology confirmed the tumor was loaded with IgG-4-positive plasma cells. The patient's vision and symptoms improved almost back to baseline, and she was discharged on high-dose steroids and thyroid supplementation. DISCUSSION: Although it remains rare, the prevalence of LH has increased due to increased awareness in the medical community and a rise in occurrence in subtypes like IgG-4-related LH (2). Primarily of autoimmune etiology with a component of genetic predisposition, the pathophysiology of LH is still not completely understood (3). The recognition of novel subtypes, immune profiling, and better imaging techniques have improved the accuracy of diagnosing the patient with LH. CONCLUSIONS: Appropriate and rapid diagnosis and treatment of suspected lymphocytic hypophysitis are crucial to prevent potentially lethal complications. Continued encountered cases and studies can aid in improvements and targeted therapies. REFERENCE #1: Angelousi A, Alexandraki K, Tsoli M, Kaltsas G, Kassi E. Hypophysitis (Including IgG4 and Immunotherapy). Neuroendocrinology. 2020;110(9-10):822-835. doi 10.1159/000506903. Epub 2020 Mar 4. PMID: 32126548. REFERENCE #2: Gubbi S, Hannah-Shmouni F, Verbalis JG, Koch CA. Hypophysitis: An update on the novel forms, diagnosis, and management of disorders of pituitary inflammation. Best Pract Res Clin Endocrinol Metab. 2019 Dec;33(6):101371. doi: 10.1016/j.beem.2019.101371. Epub 2019 Dec 12. PMID: 31866206; PMCID: PMC7078033. REFERENCE #3: Frasca F, Piticchio T, Le Moli R, Malaguarnera R, Campennì A, Cannavò S, Ruggeri RM. Recent insights into the pathogenesis of autoimmune hypophysitis. Expert Rev Clin Immunol. 2021 Nov;17(11):1175-1185. doi: 10.1080/1744666X.2021.1974297. Epub 2021 Sep 6. PMID: 34464545. DISCLOSURES: No relevant relationships by Jose Acosta-Rullan No disclosure on file for Nikhil Bhardwaj No relevant relationships by Gordana Bjekic No relevant relationships by Ruben Cabrera No relevant relationships by Raiko Diaz No relevant relationships by Ana Martinez Nunez No relevant relationships by Rafael Miret No relevant relationships by Lyanne Rolon