%0 Case Reports
%T A Case of IgG1-Lambda Multiple Myeloma With Hyperviscosity Syndrome and Cryoglobulinemia: Identification of the Subclass Fraction by Immunoelectrophoresis and Immunofixation Electrophoresis.
%A Tazoe K
%A Harada N
%A Takemura K
%A Nakamae M
%A Hino M
%J Cureus
%V 15
%N 11
%D 2023 Nov
%M 38054160
暂无%R 10.7759/cureus.48253
%X Hyperviscosity syndrome (HVS) is a complication of monoclonal plasma cell tumors. The frequency of HVS depends on the type of monoclonal protein. Immunoglobulin M (IgM) is more closely associated with HVS than IgG, and among IgG subclass monoclonal proteins, IgG3 is most frequently associated with HVS. We herein report a 44-year-old woman with multiple myeloma (MM), HVS, and cryoglobulinemia. Her monoclonal protein and cryoglobulin were IgG1-lambda (λ). She developed HVS at a lower monoclonal protein level because of the properties of the IgG1-derived monoclonal protein and cryoglobulin. Our case highlights the fact that identifying the IgG subclass is useful in predicting the risk of complicating HVS.