Severe motor-dominant neuropathy with IgM M-protein binding to the NeuAcalpha2-3Galbeta- moiety.
We report the occurrence of a relapsing, severe predominantly motor neuropathy in a 75-year-old man with an IGM-K M-protein binding to gangliosides GM2, GM3, GM4, GD1a, GT1b and LM1. Motor nerve conduction velocities were slowed with conduction block. A superficial peroneal nerve biopsy specimen revealed segmental demyelination and remyelination. The patient improved after repeated plasma exchanges, and the antibody titer decreased in association with clinical recovery. This IgM M-protein has a unique, previously unreported binding specificity for terminal NeuAcalpha2-3Galbeta- moiety in common to all gangliosides bound by the antibody except GM2. M-proteins with this affinity may be involved in the pathogenesis of this and other cases of motor-dominant demyelinating neuropathy.
Oga
T
T
Department of Internal Medicine, Yodogawa Christian Hospital, Osaka, Japan.
Kusunoki
S
S
Fujimura
H
H
Kuboki
T
T
Yoshida
T
T
Takai
T
T
D000368:Aged; D005732:Gangliosides / Q000097:blood*; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood*; D007145:Immunoglobulin kappa-Chains / Q000097:blood*; D008297:Male; D009046:Motor Neurons; D009186:Myelin Sheath / Q000473:pathology; D009431:Neural Conduction; D010265:Paraproteinemias / Q000097:blood* / Q000150:complications / Q000473:pathology; D010266:Paraproteins / Q000378:metabolism*; D010523:Peripheral Nervous System Diseases / Q000097:blood* / Q000150:complications / Q000473:pathology; D010543:Peroneal Nerve / Q000473:pathology; D011485:Protein Binding; D012131:Respiratory Insufficiency / Q000097:blood / Q000209:etiology / Q000473:pathology
D005732:Gangliosides; D007075:Immunoglobulin M; D007145:Immunoglobulin kappa-Chains; D010266:Paraproteins