Extra-articular manifestations.

Rheumatoid arthritis and spondyloarthritis, a concept which includes diseases like ankylosing spondylitis, psoriatic arthritis, and arthritis/spondylitis associated with inflammatory bowel disease, are both chronic inflammatory rheumatologic conditions. This article focuses on extra-articular manifestations, defined as diseases and symptoms not directly related to the locomotor system. The different manifestations are addressed per body system. Diagnostic and prognostic implications of these manifestations in daily practice are discussed.