Supplementary Material for: Nodular Scleritis and Pyoderma Gangrenosum Associated with Active Ulcerative Colitis: A Case Report

Introduction Pyoderma gangrenosum is a rare form of neutrophilic dermatosis, with ocular involvement being atypical. We present a rare case of ulcerative colitis (UC) complicated by nodular scleritis and pyoderma gangrenosum, both occurring almost simultaneously. Case Presentation A 55-year-old man with active UC initially presented to our hospital with anterior diffuse scleritis and a peripheral corneal ulcer in his left eye. The condition rapidly progressed to bilateral nodular scleritis. Concurrently, multiple painful abscesses developed on his trunk and head. A skin biopsy confirmed the diagnosis of pyoderma gangrenosum. Laboratory tests revealed elevated C-reactive protein and erythrocyte sedimentation rates, along with the increased proteinase-3 antineutrophil cytoplasmic antibody (PR3-ANCA). A comprehensive systemic evaluation ruled out vasculitis, and an elevated PR3-ANCA level was attributed to active UC. After excluding other potential causes of scleritis, the patient was diagnosed with bilateral nodular scleritis and pyoderma gangrenosum associated with active UC. As the scleritis did not respond to 0.1% betamethasone eye drops and prednisolone ophthalmic ointment, oral glucocorticoids were initiated, leading to significant improvement in skin and ocular inflammation as well as clinical remission of UC. Conclusions UC and pyoderma gangrenosum are rare causes of nodular scleritis. This rare case underscores the importance of reviewing a patient’s systemic disease history and recognizing systemic symptoms to identify the underlying cause of scleritis and initiate appropriate treatment in a timely manner.