The clinical value of therapeutic plasma exchange in multifocal motor neuropathy.
OBJECTIVE
Although there is evidence for a pathogenic role of humoral factors in multifocal motor neuropathy (MMN), plasma exchange (PE) is assumed to be an ineffective treatment. We set out to elucidate possible reasons for this apparent contradiction.


METHODS
A retrospective analysis of seven patients with MMN, who underwent 4 to 18 sessions of PE. Clinical response, electrophysiological parameter and anti-ganglioside antibody titers were reviewed.


RESULTS
Two patients, who had anti-ganglioside antibodies, exhibited transient clinical responses to PE, manifested by improved neurological function. Whereas electrophysiological parameters continued to worsen in all patients, anti-ganglioside antibody titers declined during PE, but increased after PE.


CONCLUSIONS
PE is of limited therapeutic value in patients with MMN, who do not respond to established treatment options. It may only be useful as an adjunctive treatment in a subset of patients. The transient decrease of anti-ganglioside-antibodies titers suggests that pathogenic humoral factors in MMN are only temporarily reduced. Further, PE treatment alone is insufficient to prevent axons from continuing degeneration, which may explain the failure of PE to substantially influence the disease course of patients with MMN.
Lehmann
Helmar C
HC
Department of Neurology, Heinrich-Heine-University of Düsseldorf, Germany. helmar.lehmann@uni-duesseldorf.de
Hoffmann
Felix R
FR
Fusshoeller
Andreas
A
Meyer zu Hörste
Gerd
G
Hetzel
Rüdiger
R
Hartung
Hans-Peter
HP
Schroeter
Michael
M
Kieseier
Bernd C
BC
D000328:Adult; D000368:Aged; D000906:Antibodies / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D005732:Gangliosides / Q000276:immunology; D006801:Humans; D008297:Male; D008875:Middle Aged; D016472:Motor Neuron Disease / Q000097:blood / Q000276:immunology / Q000503:physiopathology / Q000628:therapy*; D009431:Neural Conduction / Q000502:physiology; D010951:Plasma Exchange / Q000379:methods*; D012189:Retrospective Studies; D016896:Treatment Outcome
D000906:Antibodies; D005732:Gangliosides