[Immunoproliferative disease of the small intestine. A case of polymeric IgA with evolution to lymphoma].

Immunoproliferative disease of the small intestine (IPDSI) is rare and although it is more frequent in mediterranean countries it has more exceptionally been described in Western countries. IPDSI is characterized by diffuse infiltration of the small intestine mucose by lymphoblastic cells and over time may evolve to the development of lymphoma, generally of an immunoblastic nature. Another peculiarity of the disease is its association with heavy alpha chain disease (HACD). Several types of paraproteinemia may appear in the serum of patients, very seldom in the form of polymeric IgA, with the evolution of the cases reported in the literature not leading to the development of heavy chain disease or lymphoma. We herewith present an exceptional case of IPDSI in whom the association of HACD was discarded and in whom polymeric IgA paraproteinemia which evolved to the development of lymphoma was observed.