Bilateral Myelomatous Pleural Effusion in a Patient with IgA Kappa Multiple Myeloma.

Multiple myelomas is a neoplastic plasma cell disorder that accounts for one percent of all cancers and 13% of hematologic malignancies. Although primarily known to be a bone marrow disorder, it can metastasize to extramedullary sites or it can present as a solitary extramedullary plasmacytoma. Primary pleural effusion from myeloma is rare, occurring in less than one percent of the patients. The following case report highlights a case of bilateral pleural effusion, directly attributable to multiple myeloma after other causes were ruled out. The diagnosis was made using cytology and immunohistochemical (IHC) staining of the pleural fluid. Myelomatous pleural effusion (MPE) is a poor prognostic feature heralding an aggressive underlying disease state, as represented in this case.