There are over 200 disorders that involve connective tissue. Certain disorders are characterized by overactivity of the immune system with resulting inflammation and systemic damage to the tissues (eg, SLE [see Autoimmune Rheumatic Disorders: Systemic Lupus Erythematosus (SLE)] and juvenile idiopathic arthritis [formerly known as juvenile RA—see Juvenile Idiopathic Arthritis: Juvenile Idiopathic Arthritis (JIA)]). Other disorders involve biochemical abnormalities or structural defects of the connective tissue. Some of these disorders are inherited, and some are of unknown etiology.

Last full review/revision February 2008 by Frank Pessler, MD, PhD; David D. Sherry, MD