Anti-Neuronal Antibodies in Patients with Sjögren's Syndrome and Acute Cerebellar Ataxia: Two Case Reports

We herein report two patients presenting with acute cerebellar ataxia shortly after the diagnosis of Sjögren's syndrome (SS). Two women (43- and 55-year-old) patients showed normal MRI, inflammatory cerebrospinal fluid (CSF) findings, and moderate response to immunotherapy in long-term follow-up. A broad panel of antibodies was negative for the 43-year-old patient. However, indirect immunohistochemistry showed serum/CSF antibodies with a distinctive reactivity pattern on rat brain sections. The 55-year-old patient showed anti-glutamic acid decarboxylase in serum and CSF. Five control SS patients without neurological symptoms did not have anti-neuronal antibodies. Anti-neuronal antibody investigation may contribute to the differential diagnosis of neurological involvement in SS.