[Neuropathy in Waldenstrom's macroglobulinemia]

The association of a neuropathy and a paraproteinaemia such as Waldenström's macroglobulinaemia is frequent and not fortuitous. This paper reports a slowly progressive, predominantly sensory neuropathy, occurring in a 69-year-old man, as the first sign of a Waldenström's macroglobulinaemia. A saphenous [correction of sural] nerve biopsy revealed a mixed process of primary demyelination and axonal degeneration. Accumulations of immunoglobulin M were observed in the myelin sheets and the perineurium by immunocytochemistry. Infiltrations of inflammatory blood cells and accumulations of amyloid material were absent in the peripheral nerve. The axonal loss was most prominent in central areas of the nerve fascicles. This find supports the hypothesis of an ischemic mechanism for the axonal degeneration plus secondary demyelination, associated to a direct immunological attack against myelin. The various types of peripheral nerve involvement in Waldenström's macroglobulinaemia, as well as the admitted mechanisms of nerve lesion and the therapeutic approaches to this still unclear neuropathy are briefly reviewed.