Connective tissue disease manifested as multiple myeloma

A diagnosis of Sjögren's syndrome or rheumatoid arthritis was made in five women in whom multiple myeloma was first suspected. All had mild symptoms of sicca or arthritis, positive tests for rheumatoid factor or antinuclear antibody, and markedly increased IgG immunoglobulins. A connective tissue disorder may produce the characteristic electrophoretic pattern of multiple myeloma.