Treatment of central nervous system involvement associated with primary Sjögren's syndrome

Sjögren's syndrome (SS) is a chronic autoimmune disease that mainly affects the exocrine glands and usually presents with sicca symptoms of the main mucosal surfaces. The prevalence and the type of central nervous system (CNS) tissue damage caused by SS are debatable. The wide spectrum of CNS manifestations, different classification criteria used and unclear inclusion or exclusion criteria pose some difficulty reviewing these studies. Careful examination of the SS patients and to be aware of neurological findings which may be associated with suspicious CNS involvement is highly important. Central nervous system may also hypothetically have a role in the pathophysiology of SS. The wide spectrum of CNS involvement includes focal (sensorial and motor deficits, brain stem, cerebellar lesions, seizure, migraine etc.) or non-focal (encephalomyelitis, aseptic meningitis, neuropsychiatric dysfunctions), spinal cord (myelopathy, transverse myelitis, motor neuron disease etc.) findings or multiple sclerosis-like illness and optic neuritis. Evolving imaging techniques such as single photon emission computed tomography (SPECT), magnetic resonance spectroscopy or magnetization transfer imaging are promising for better understanding the nature of CNS involvement in SS. Treatments usually comprise symptomatic approach in milder cases however, pulse cyclophosphamide and steroids or other immunosuppressants (chlorambucil or azathioprine) are required in cases with progressive symptoms leading to neurological impairment. Anti-TNF agents (infliximab and etanercept) and B cell targeted therapies (rituximab and epratuzumab) are used in primary SS however their efficacy on CNS manifestation is still unclear. Randomized, multicenter studies are warranted to confirm the efficacy of treatment regimes which were reported to be effective in anecdotal reports or in small uncontrolled series. This article reviews the clinical approach to current therapy of CNS involvement in patients with primary SS.