PARKINSON’S DISEASE
P
P a rk in s o n ’s d is e a s e
A neurological disorder that is the most
common cause of
p a r k in s o n is m
.
CAUSES AND INCIDENCE
Parkinson’s disease is caused by degen-
eration of, or damage to, cells in the
b a s a l g a n g lia
of the brain. As a result,
there is a deficiency of the neurotrans-
mitter
d o p a m in e
(which is needed for
the control of movement). The condition
occurs mainly in elderly people and is
more common in men.
For
further
information
on
the
processes leading to Parkinson’s disease,
see the illustrated box, previous page.
SYMPTOMS AND SIGNS
The main symptoms develop gradually,
over several months or even years. The
disease usually begins as a slight tremor
of one hand, arm, or leg, w hich is
worse when the hand or lim b is at rest.
Later, both sides of the body are
affected, causing stiffness, weakness, and
trembling of the muscles. Symptoms
include a stiff, shuffling walk that may
break into uncontrolled, tiny running
steps; constant hand tremors, sometimes
accompanied by shaking of the head; a
permanent rigid stoop; and an unblink-
ing, fixed expression. Everyday activities
such as eating, washing, and dressing
become very difficult.
The intellect is unaffected until late in
the disease, although the affected per-
son’s speech may become slow and
hesitant, and the handwriting usually
becomes very small.
D e p re s s io n
is a
common complication.
TREATMENT
There is no cure, but drug treatment,
p h y s io t h e ra p y
,
and, rarely, surgery can
help to relieve symptoms. In the early
stages of Parkinson’s disease, exercises,
special aids in the home (see
d is a b ilit y
) ,
and support can improve the affected
person’s
morale
and
mobility.
Drug
treatment is used to minimize symp-
toms in later stages. These treatments
cannot halt the degeneration of brain
cells, but can m inimize the symptoms
by
helping
to
correct
the
chemical
imbalances in the brain.
In some cases, an
a n t ic h o lin e rg ic d ru g
such as trihexyphenidyl
(benzhexol)
may initially be given to reduce tremor.
Anticholinergic drugs can be effective
for several years, but may cause side
effects
such as
dry
mouth,
blurred
vision, and difficulty in passing urine.
L e v o d o p a
,
which the body converts
into dopamine, is usually the most effec-
tive drug. It may, however, cause side
effects such as nausea and vomiting;
therefore, the dose is increased gradually,
and the drug may be given in combina-
tion
with
benserazide
or
carbidopa.
Levodopa is usually effective for several
years, but the effects gradually wear off.
Drugs that may be used in conjunction
with it, or as substitutes for it, include
a m a n ta d in e
and
b ro m o c rip tin e
.
Surgical operations on the brain are
occasionally performed, if the affected
person is young and otherwise in good
health. New therapies that are still being
assessed include replacement of dam-
aged tissue with transplanted brain cells,
and deep brain stimulation with electri-
cal impulses to reduce tremor.
OUTLOOK
If left untreated, the disease progresses
over 10 to
15
years, leading to severe
weakness and incapacity. Some sufferers
eventually
develop
d e m e n t ia
.
Modern
drug treatments, however, can provide
considerable relief from the symptoms
and give affected people a much im -
proved quality of life.
p a ro n y c h ia
An infection of the skin fold at the base
or side of the
n a il
.
The affected area
becomes swollen and painful, and there
may be a buildup of pus.
Paronychia may be acute (caused by
bacteria) or chronic (usually caused by
C
a n d i d a a i b i c a n s
). The condition is most
common in women, particularly those
with poor circulation and whose work
involves frequent contact with water. It
also affects people with skin disease
involving the nail fold.
Treatment is with
a n tifu n g a l d ru g s
or
a n t ib io t ic d r u g s
.
If pus has collected in
the area, it may need to be drained sur-
gically. To prevent the occurrence of
paronychia, gloves should be worn for
all tasks that involve putting the hands
in water, and the hands should be dried
thoroughly after washing.
p a ro tid g la n d s
The largest of the three pairs of
s a liv a ry
glands.The parotid glands are situated on
each side of the face, just above the angle
of the jaw and in front of the ear. They
secrete saliva into the mouth through a
duct that opens into the inner cheek,
level with the second molar tooth.
The parotid glands may develop vari-
ous disorders that can affect all of the
salivary glands, such as infections, ab-
scesses (collections of pus), or calculi
(stones). One disorder that specifically
LOCATION OF THE
PAROTID GLANDS
The glands are situated deep in the
angle of the jaw and secrete saliva
into the mouth. Mumps may affect
other salivary and exocrine glands.
affects these glands is
m u m p s
,
w hich
causes inflammation of one or both
glands. Another is a form of noncancer-
ous
tumour,
pleomorphic
adenoma,
w hich is slow-growing and painless but
may rarely become cancerous.
p a ro titis
Inflammation
of the
p a ro t id
g la n d s
,
w hich is often due to infection with the
m u m p s
virus.
p a ro x e tin e
A
s e le c t iv e s e ro t o n in re u p ta k e in h ib it o r
antidepressant drug. Possible side effects
of paroxetine include nausea, indiges-
tion, and appetite loss.
p a ro x y sm
A sudden attack, worsening, or recur-
rence of symptoms or of a disease; a
s p a s m
or
s e iz u r e
.
p a ro x y s m a l n o c tu rn a l d y s p n o e a
Acute breathing difficulty that occurs
suddenly at night, usually waking the
person from sleep. The condition most
commonly
affects
people
suffering
from congestive
h e a rt f a ilu re
with
p u l-
m o n a ry o e d e m a
(a buildup of fluid in the
lungs); in these cases, it is caused by
fluid leaking out of the blood vessels
into the air spaces of the lungs once the
person is lying down. It may also occur
in people with chronic lung diseases.
p a ro x y s m a l ta c h y c a rd ia
A
form
of tachycardia
(abnormally
rapid heartbeat) that usually comes on
abruptly and stops just as suddenly. It
590
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