Papilledema as the initial presentation of Castleman disease.

Castleman disease is a rare lymphoproliferative disorder that has many presentations ranging from unifocal or multifocal mass lesions to a monoclonal gammopathy. It has features that may overlap with osteosclerotic myeloma or POEMS (polyneuropathy, organomegaly, endocrinopathy, M protein, skin changes) syndrome. We report a patient with papilledema, enlarged lymph nodes, and monoclonal IgG, who subsequently developed a polyneuropathy. Biopsy of enlarged mediastinal lymph nodes confirmed the diagnosis of Castleman disease.