BACKGROUND: An association between motor neuron disease and Waldenstrom dis
ease is rarely reported in the literature. The association with peripheral
neuropathy and IgM monoclonal gammapathy is well known. CASE
REPORT: In our patient the malignant monoclonal gammapathy had an unusual a
ntigen pattern. This patient was MAC (myelin-associated glycoprotein) negat
ive but showed a very positive serology for CM 1 ganglioside and SCPC (3-su
lfated glycuronly paragloboside).
DISCUSSION: This is the fifth such case to be reported associated a maligna
nt dyglobulinemia with an MAG-negative IgM gammapathy. it is the first case
with positive serology for both the GM 1 ganglioside and SGPG. (C) 2000, M
asson, Paris.