Neurologic Involvement in Rheumatic Diseases

For a long time, the central nervous system (CNS) has been considered a privileged anatomical site, protected from immunologic threats by an intact blood–brain barrier (BBB) which ensures a strictly regulated interaction with the systemic blood circulation. However, several conditions can alter the integrity of the BBB, allowing the access of pro-inflammatory mediators, immune cells, and autoantibodies into the CNS. Moreover, recently, neuroinflammation has emerged as a key process shared by many neurological conditions, both as a causative factor and a secondary response to nervous system insults in the context of systemic diseases. As rheumatic diseases represent a broad spectrum of systemic conditions manifested by multisystem involvement and mediated by autoimmunity and inflammation, neurologic involvement may occur at any point in the disease process, representing a diagnostic and therapeutic challenge for the clinicians. This chapter provides a synthetic overview of both central and peripheral neurological involvement in some of the major rheumatic systemic autoimmune diseases.