Unusual causes of episcleritis
A number of the collagen diseases may be associated with episcleral involvement. These include rheumatoid arthritis, polyarteritis nodosa, relapsing polychondritis, and systemic lupus erythematosus. Episcleral nodules have rarely been reported in temporal arteritis. In 2 of the authors' cases, sarcoidosis with erythema nodosum and Weber Christian disease were present, and histopathologic examination of the biopsy specimens served to confirm the clinical impression. In 2 other cases, purely local ocular disease was present, and excision of the nodule served both diagnostic and therapeutic purposes. The presence in case 3 of episcleral nodules and orbital pseudotumor was unexpected. This association deserves further investigation. Evaluation of episcleral nodules should include a complete medical examination, soft tissue roentgenograms, and biopsy specimens of those nodules which are refractory to local treatment. An indication for biopsy in 2 of the cases was the appearance of corneal dellen. The association between episcleral nodules and corneal dellen has been previously reported.
