[Neurological manifestations in monoclonal gammapathies. Pure neurological manifestations. Immunofluorescence study].

Analysis of 105 peripheral and central nervous system complications in 1062 monoclonal gammapathies draws attention to two types of phenomena. The possibility of pure neurological manifestations of IgM monoclonal gammapathies with macroglobulinorachia leads to discussion of their nosological position in relation to Waldenström's disease, Burkitt's lymphoma and Marek's disease. It is suggested that these cases should be reclassified under the heading "secreting neurolymphomatosis". Immunofluorescence and electron microscopy of 10 biopsies of the peripheral nerve showed deposits of monoclonal immunoglobulin whose function in determining peripheral neuropathies is discussed. The simultaneous presence of lymphoid infiltration, amyloid deposits and the monoclonal immunoglobulin (M component) suggests that this immunoglobulin could be the link between the cellular infiltrate secreting it and amyloid infiltration which would be the visible manifestation of it.