Low-grade non-Hodgkin B-cell lymphoma presenting as sensory neuropathy

Low-grade non-Hodgkin B-cell lymphoma was found during the evaluation of 3 aged patients with predominantly sensory neuropathy of mild to moderate severity. Presenting manifestations were sensory ataxia and right ulnar mononeuropathy in a 75-year-old man, and painful dysesthesias of the legs in two 78-year-old women. A neurophysiological study showed mainly axonopathic alterations. M-protein was present in all cases (Ig-kappa in two, triclonal gammopathy IgG(kappa)/IgM(kappa)/IgM-lambda in one). The male patient had IgM antisulfatide antibody in high titer, whereas the other 2 patients had cryoglobulinemia (type II and type III, respectively). Our report emphasizes the occurrence of mild polyneuropathy as presenting manifestation of low-grade non-Hodgkin lymphoma, different from the clinicopathological entity of neurolymphomatosis, in which severe nerve damage occurs in association with manifest lymphoma, related to nerve infiltration by lymphomatous cells. Alternative pathogenetic mechanisms, such as antibody-mediated nerve damage, or vasa nervorum changes caused by cryoglobulin, may be implicated in our cases. Non-Hodgkin lymphoma should be considered in the diagnostic evaluation of polyneuropathy of unknown cause, especially in patients with paraproteinemia and/or cryoglobulinemia.