Monoclonal gammopathies and the related autoimmune manifestations in Taiwan.

A total of 50,000 patients were surveyed for the presence of monoclonal immunoglobulins during the past two decades. There were 411 cases of monoclonal gammopathies including 243 cases of plasma cell neoplasms and 168 cases of secondary plasma-cell dyscrasia. Among the 227 cases of multiple myeloma and Waldenström's macroglobulinemia, there were 49.3% IgG class, 22.9% IgA class, 9.7% IgM class and 13.2% light chain type. In addition, there were 1.3% of nonexcretory myeloma including an IgM type. A relatively high frequency (4.8%) of IgD M-proteins was detected but heavy chain disease was not encountered in the present series. Purified M-components from patients with possible autoimmune manifestations were subjected to immunofluorescence studies. Autoimmune activity of M-proteins was found in a patient of Waldenström's macroglobulinemia with peripheral neuropathy, and another patient of cryofibrinogenemia with recurrent purpura and gangrene. In conclusion, a high frequency of IgD myeloma is found in Chinese patients of this area. M-components may have autoimmune activity resulting in unusual clinical manifestations.