Noninfectious Scleritis

The intrinsic nature of scleritis poses an ultimate challenge to the skill of the managing ophthalmologist. The chronicity of the disease, its tendency to exacerbate and remit, its relationship with many ocular and systemic diseases, and its variable response to speciÞc treatment combine to complicate the management.

Scleritis may occur in association with a variety of noninfectious and infectious local and systemic disorders. Within the noninfectious universe, several types of diseasesÑimmune mediated, dermatologic, metabolic, foreign body induced, and chemical substance inducedÑcan cause scleritis (Table 6.1).

Systemic immune-mediated diseases, particularly the vasculitides, are the most severe and destructive conditions that may involve sclera. The presence, degree, and nature of scleritis may correlate with the chronicity, severity, and activity of the systemic immune-mediated associated disease. For example, diffuse or nodular scleritis may progress to necrotizing scleritis in association with the development of a vasculitic process in collagen diseases, such as rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE); necrotizing scleritis may appear suddenly in association with primarily vasculitic diseases, such as polyarteritis nodosa (PAN). Scleritis also correlates with the type of vasculitic involvement of the associated disease. For example, scleritis is frequently seen in association with vasculitic diseases that affect predominantly smalland medium-sized vessels, such as RA, SLE, arthritis and inßammatory bowel disease (IBD), granulomatosis with polyangiitis

(GPA) (Wegener), or PAN; scleritis is less commonly found in association with vasculitic diseases that affect predominantly large-sized arteries, such as ankylosing spondylitis (AS), reactive arthritis (ReA), or giant-cell arteritis (GCA). In some cases, scleritis may antedate the onset of a potentially lethal systemic immune-mediated disease. Early diagnosis and subsequent therapy of the underlying disease may improve the ocular and life prognoses.

Dermatologic and metabolic conditions may secondarily cause scleritis. Foreign bodies embedded in the sclera may excite a granulomatous inßammatory reaction, and scleral acid or alkali chemical injuries may lead to scleritis and subsequent collagen destruction.

The presence of scleritis, therefore, demands a thorough systemic and ocular evaluation to deÞne any associated disease. A detailed past general and ocular history, exhaustive review of systems, standard physical examination, meticulous slitlamp examination, and appropriate ancillary tests must be included as part of the diagnostic strategy for the patient with scleritis.

Ophthalmologists are not only Òeye doctors.Ó They are physicians who must consider the systemic manifestations of the patient and decide whether or not there is any interconnection between systemic and ocular Þndings. They must be competent enough to promptly diagnose and treat an underlying systemic disease that is associated with ocular inßammation, such as scleritis. Ophthalmologists, therefore, must remain current with the systemic disorders that are associated with scleritis.