Isolated Episcleral Plasmacytoma Mimicking Episcleritis in a Patient with Benign Monoclonal Gammopathy

The document described a unique case of a 61-year-old patient with an isolated episcleral plasmacytoma that mimicked episcleritis. Plasmacytomas typically grow in the bone marrow, but solitary plasmacytic tumors outside the bone marrow are rare and usually involve areas like the oropharynx and upper respiratory tract. In this case, the patient presented with an inflammatory episcleral nodule and mild pain in the left eye, initially diagnosed as episcleritis. There was no evidence of rheumatic disease, and standard treatments like dexamethasone eyedrops were ineffective, highlighting the unusual presentation and diagnostic challenge of this condition.