Scleritis is a rare inflammatory disease which affects the sclera and its adjacent structures such as the episclera, uvea, and cornea. Scleritis can cause severe, disabling pain, destruction of scleral tissue, and the risk of significant visual loss.

The pathophysiology of scleritis is complex, incompletely understood, and complicated by the heterogeneity of the disease as well as the dearth of studies into the immunopathology.