Constipated plasma cells associated with monomeric macroglobulinemia

Abstract Low molecular weight macroglobulinemia was observed in a patient with chronic pulmonary injection. An enlarged cervical lymph node contained many abnormal plasma cells, which were distended with immunoglobulin; this material appeared to be released into lymph spaces when the cells burst. The macroglobulin production is considered to be a nonneoplastic reactive immune response to the pulmo-nary injection. It is postulated that the association of constipated plasma cells and 7s-IgM can best be explained as an acquired deject in macroglobulin polymerization.