Intestinal involvement in Waldenstrom's macroglobulinemia

A female patient, 68 yr old, with Waldenstrom's macroglobulinemia is described in whom malabsorption and weight loss were the chief clinical manifestations. Deposits by hyaline material in the lamina propria of the small intestine produced bizarre, clubbed villi and were associated with large foamy macrophages of uncertain origin. There were also various lymphoid cells in the lamina propria that included plasma and plasmacytoid cells having amorphous intranuclear inclusions of the type often found in Waldenstrom's macroglobulinemia. The hyaline material deposited in the villi was thought to tbe macroglobulin. Local production of macroglobulin by abnormal lymphoid cells in the villi may have contributed to its deposition there. The deposits were probably a major factor causing malabsorption.