Monocytoid B cell lymphoma associated with antibodies to myelin-associatedglycoprotein and sulphated glucuronyl paragloboside

Monocytoid B cell lymphoma (MBCL) is an immunologically and morphologically well-defined low-grade lymphoma with a predilection for lymph nodes of the parotid region. We describe an association of MBCL with antimyelin-associa ted glycoprotein (MAG) polyneuropathy in a 53-year-old male. The diagnosis of stage IV MBCL with nodular bone marrow infiltration, Sjogren's syndrome and sensorimotor polyneuropathy was made in October 1996. Serum immunoelect rophoresis demonstrated IgM kappa paraprotein. This was then cross-reacted with epitopes of MAG and sulphated glucuronyl paragloboside (SGPG) on myeli n sheaths, and detected by thin layer chromatography and Western blot. Dire ct immunofluorescence of a sural nerve biopsy showed loss of myelin fibres, segmental demyelinization and IgM deposits on the myelin sheaths. The cere brospinal fluid was normal. After six cycles of chemotherapy (ChIVPP protoc ol), all the patient's haematological parameters normalized accompanied by an improvement in neurological signs. The improvement of the polyneuropathy after chemotherapy indicates that the autoimmune anti-MAG and anti-SGPG an tibodies resulted from the neoplastic lymphoid proliferation. Copyright (C) 2001 S. Karger AG, Basel.