The term scleritis describes a chronic inflammation that involves the outermost coat and skeleton of the eye. Disease can be isolated to the eye, but in up to half of affected individuals it occurs in the context of an immune-mediated systemic inflammatory condition, such as rheumatoid arthritis or Wegener's granulomatosis. Although uncommon, scleritis is often extremely painful, can lead to vision-threatening complications (and involvement of other ocular tissues), and is considered to confer an increased risk of mortality in patients with rheumatoid arthritis.