Anti-Sjögren's-syndrome-related antigen A autoantibodies (Anti-SSA antibody) and meningoencephalitis: Sjögren's syndrome waiting to be unveiled? A case series and review of literature.

Aseptic meningoencephalitis (AME) constitutes a variable proportion of meningoencephalitis. Patients with AME are not routinely evaluated for autoimmune disorders. Primary Sjögren's syndrome (pSS) is a prevalent, but under suspected systemic autoimmune disease characterised by exocrinopathy, though sicca symptoms may not be the dominant or presenting feature. This study was undertaken to enumerate the clinical, radiological and laboratory features of meningoencephalitis related to pSS among the total cohort of meningoencephalitis admitted in our hospital. Retrospective patient records were screened for diagnosis of meningoencephalitis from April 2016 to March 2020. Those patients with anti-SSA positivity and clinical diagnosis of pSS were included. We have reviewed all cases of Sjögren's syndrome with meningoencephalitis available in literature. Four patients with meningoencephalitis with pSS were identified. Their clinical presentations, investigations, and good response to steroids have been described with special emphasis on evolving clinical features. In all patients, sicca features were absent. Anti-SSA was positive in all. The diagnosis of pSS was considered after ruling out all infectious and other autoimmune aetiologies. Two had extra-neurological organ manifestations and required addition of second line immunosuppressive agents for optimum disease control. Consistent with this case series, absent sicca symptoms have been described in pSS patients presenting with meningoencephalitis in literature. This case series is of special interest as it describes the initial presentation of pSS as meningoencephalitis with sicca features in absentia, thereby highlighting the need for a high index of suspicion and the need for workup for pSS in AME.