http://link.springer.de/link/service/journals/10072/bibs/1022002/10220151.htm
Neurological Sciences
Abstract Volume 22 Issue 2 (2001)
pp 151-154
O. Gout
Federation of Neurology, Hôpital
de la Salpêtrière, and Neurology Service Foundation A. de
Rothschild, Paris, France
Abstract.
Two problems must be considered in
regard to the relationship between vaccinations and MS:
In most instances, the role of the
vaccine is based on a temporal link between the injection and the onset
of neurological disease, and more rarely to a positive reintroduction.
Acute disseminated encephalomyelitis
(ADEM), a monophasic and multifocal illness of the white and grey matter,
has been observed following various viral or bacterial infections as well
as vaccine injections for diseases such as pertussis, tetanus and yellow
fever.
The similarities between ADEM and
experimental allergic encephalitis (EAE) are suggestive of an immunological
process.
In addition to the dramatic presentation
of ADEM, more limited white matter involvement, such as optic neuritis
or myelitis, has bee reported following vaccine injections, and has occasionally
been counted as the first attack of MS.
In France, 25 million inhabitants,
almost half of the population, were vaccinated against hepatitis B (HB)
between 1991 and 1999.
Several hundred cases of an acute
central demyelinating event following HB vaccination were reported to the
pharmacovigilance unit, leading to a modification of vaccination policy
in the schools and the initiation of several studies designed to examine
the possible relationship between the vaccine and the central demyelinating
events.
The results of these studies failed
to establish the causality of the HB vaccine.
Nevertheless, molecular mimicry between
HB antigen(s) and one or more myelin proteins, or a non-specific activation
or autoreactive lymphocytes, could constitute possible pathogenetic mechanisms
for these adverse neurological events.
© Springer-Verlag Italia 2001
Answers to these questions are difficult
due to the paucity of reported cases, or ignorance of the precise frequency
of neurological adverse events in vaccines based on prospective studies,
and finally by the lack of a well established pathophysiology.