Ocular surface squamous neoplasia in a patient following oral steroids for contralateral necrotising scleritis.

A male patient in his 70s presented with left eye necrotising scleritis. His ocular history was significant for pterygium excision with mitomycin C 3 months prior in the affected eye, open-angle glaucoma, nuclear sclerosis cataract and previous sixth cranial nerve palsy. Scleral culture was negative and blood work was positive for rheumatoid factor and HLA-B27. The patient was treated for necrotising scleritis with oral doxycycline, vitamin C, ranitidine and prednisone with gradual taper over 45 days. Two months after initiating treatment, his necrotising scleritis achieved complete resolution; however, a new-onset ocular surface squamous neoplasia (OSSN) was identified at the temporal limbus of the contralateral eye. He was treated with topical interferon alpha-2b 1 million IU qid and achieved complete resolution after 4 months. The case highlights both the acute precipitation of OSSN following oral steroids and a sight-threatening complication following pterygium excision.