Peripheral neuropathy in monoclonal gammapathy with cryoglobulinemia and arteritis.

We report a patient with IgM gammapathy, cryoglobulinemia, Raynaud's phenomena, purpura hyperglobulinemica of the legs and polyneuropathy. Endoneural vasculitis with infiltrations of eosinophilic and neutrophilic granulocytes and an extensive loss or Wallerian degeneration of myelinated nerve fibers were seen on histopathologic examination of a sural nerve biopsy specimen. The microscopic picture differed somewhat from that observed previously in cryoglobulinemic vasculitis. Although vasculitis is most often believed to represent an immunologically mediated lesion, we propose an alternate explanation, namely, that the disease manifestations in the present case were secondary to cold-induced effects of the cryoglobulin on the microcirculation.