Scleritis: Differentiating infectious from non-infectious entities.

Scleritis is a rare painful ocular disorder, associated with severe ocular pain and tissue destruction. Although a majority of these cases are immune mediated and at least half of these are associated with systemic immune-mediated diseases, a smaller minority are due to infections of the sclera. The two conditions closely mimic each other, and a thorough knowledge of the subtle differences is necessary in order to reach a timely diagnosis.