Page 33 - Handbook of Electronic Assistive Technology

20 HANDBOOK OF ELECTRONIC ASSISTIVE TECHNOLOGY

MULTIPLE SCLEROSIS
In the United Kingdom and similar societies, multiple sclerosis (MS) is the commonest
disabling, neurological problem in young adults with a prevalence of 1.2/1000.
The exact reasons why MS happens are partly still being discovered; there is so much
we still need to learn about the disease. Sticking it in an autoimmune section would
cause huge grief to half the neurology community and just a transient nod from the other
half. Many believe that there is at least partially an autoimmune element in that our own
lymphocytes attack the myelin around nerve axons, disrupting the speed of messages.
Over time axons and neurons deteriorate and a more progressive disease takes hold,
with increasing spasticity and disability. There is also a variety of genetic and environ-
mental factors.
Episodes of subtle signs and symptoms initially resolve but over a longer period the
clinical signs from the deficits may stay and progress. Repeated episodes occur as new
areas of damage occur within the CNS. MRI scans show areas of demyelination of differing
ages and stages.
There are four types dependent on the speed of onset and progression: relapsing–
remitting, secondary and primary progressive and progressive–relapsing. Initial signs are
variable but usually include sensory, visual or motor disturbance. Before the problems
become multiple there is a group of around 30% who do not progress.
A variety of treatment options have been tried and once again this is an area of huge
trial resource internationally, using oral, injected or intrathecal antiinflammatory, immune
modulating or immunosuppressive drugs or more recently using the power of restorative
stem cells.
Support in mobility, communication and ways to maintain independence are key in
any individual management programme.
Other autoimmune disorders of the CNS are found at the brain and spinal cord levels
and once again specific patterns are associated with specific organisms. We have already
mentioned postviral infective encephalitis, but the autoimmune encephalitides are caused
by antibodies attacking proteins within the CNS. Examples include the increasingly recog-
nised N-methyl-d-aspartate receptor antibodies; encephalitis, sparked off by a number of
organisms, including herpes simplex and varicella (chicken pox) viruses; poststreptococ-
cal syndromes such as Sydenham’s chorea; and acute disseminated encephalomyelitis, a
severe autoimmune-inflammatory disease, rare but particularly seen in childhood.
Systemic immune disorders such as sarcoidosis and systemic lupus erythematosus can
also affect the CNS.
PARKINSONISM
• Overall prevalence – 1.5/1000.
• Over age 60 prevalence – 1/100.
• Over age 80 prevalence – 3/100.

At least seven genes have been implicated in the degeneration of the dopamine trans-
mitting neurons of the basal ganglia area of the substantia nigra. This causes a chemical