Inflammatory arthritis is a group of diseases characterized by inflammation of the synovial membrane in the joints and, often, other tissues throughout the body. Some forms of inflammatory arthritis are autoimmune diseases, conditions in which the body’s immune system attacks healthy tissue, also known as systemic autoimmune rheumatic diseases (SARD). Examples of SARDs that cause inflammatory arthritis include rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), Sjögren’s syndrome (SjS), systemic sclerosis (SSc), polymyositis (PM), and dermatomyositis (DM). Other types of inflammatory arthritis include axial spondyloarthritis (formerly called ankylosing spondylitis) and psoriatic arthritis, along with gout which is also considered a metabolic arthritis and discussed under it's own heading.

As a group, inflammatory arthritic diseases are characterized by joint pain, swelling, warmth, and tenderness in joints, and can cause deformity and loss of function of affected joints.  Since these diseases are systemic, they may be associated with involvement of other tissues or organs including the skin, eye and bowel. In addition, in these diseases, blood tests provide evidence of inflammation and some conditions are useful markers that assess disease likelihood. Inflammatory arthritis conditions are sometimes difficult to diagnose and distinguish; all patients suspected of having an inflammatory arthritis should be referred to a rheumatologist for evaluation and management. Arthritis occurring in children and adolescents is referred to as juvenile idiopathic arthritis (formerly juvenile rheumatoid arthritis) and is discussed in the Juvenile Arthritis heading.

Only the most common inflammatory arthritides will be discussed below. A listing of the many types of inflammatory arthritis and related conditions can be seen by clicking HERE.