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. Diagnostic delay can lead to a poor outcome both due to the destruction caused by the uncontrolled infection and also due to propagation of the infection with the use of corticosteroids which may have been started for presumed immune mediated scleritis. In this review, we present the clinical features, etiological agents, and the differentiating features between immune and infectious scleritis. We also present diagnostic and management guidelines for managing scleral infection.