Patterns of Amyloidosis and Their Association with Plasma-Cell Dyscrasia, Monoclonal Immunoglobulins and Bence-Jones Proteins

Abstract

The frequency of monoclonal immunoglobulins and Bence-Jones proteins was studied in 100 cases of amyloidosis classified according to the patterns of distribution of amyloid. Monoclonal immunoglobulins, Bence-Jones proteins (or both) were documented in all 50 Pattern I ("primary-type") cases, nine of 17 Pattern II ("secondary-type") cases, 26 of 30 Mixed Pattern I and II cases and in all three cases of localized amyloidosis. Forty-six per cent of the patients with amyloidosis (all patterns) had Bence-Jones protein only, without a monoclonal immunoglobulin, as compared with 21 per cent of cases of myeloma without associated amyloidosis. There was a higher proportion of λ-type Bence-Jones proteins in the amyloidosis group, and amyloid-related proteins were relatively more anionic than nonamyloid-related proteins. It is postulated that amyloid-related monoclonal immunoglobulins and Bence-Jones proteins may be autoantibodies or fragments of autoantibodies directed against normal tissue constituents. (N Engl J Med 290:473–477, 1974)