HEMIBALLISMUS
HEPATITIS, ACUTE
H
young people is usually caused by
migraine.
In older people, it occurs in
transient ischaemic attacks.
Permanent
homonymous hemianopia is usually
caused by a
stroke,
but it may result
from brain damage by a tumour, injury,
or infection. Hemianopia may also be
caused by pressure on the optic nerve
from a
pituitary tumour.
hemiballismus
Irregular
and
uncon-
trollable flinging movements of the arm
and leg on
1
side of the body, caused by
disease of the
basal ganglia.
(See also
athetosis; chorea.)
hemicolectomy
The surgical removal
of half, or a major portion, of the
colon.
(See also
colectomy.)
hemiparesis
Muscular weakness or par-
tial
paralysis
affecting only
1
side of the
body (see
hemiplegia
).
hemiplegia
Paralysis
or weakness on 1
side of the body, caused by damage or
disease affecting the motor nerve tracts
in the opposite side of the brain. A com-
mon cause is a
stroke.
Others include
head injury, brain tumour, brain haemor-
rhage, encephalitis, multiple sclerosis,
complications of
meningitis
, or a
con-
version disorder.
Treatment is for the
underlying cause, and is carried out in
conjunction with
physiotherapy
.
Henoch-Schonlein purpura
Inflam-
mation of small blood vessels, causing
leakage of blood into the skin, joints,
kidneys, and intestine. The disease is
most common in young children, and
may occur after an infection such as a
sore throat. The condition may also be
due to an abnormal allergic reaction.
The main symptom is a raised purplish
rash on the buttocks and backs of the
limbs. The joints are swollen and often
painful, and colicky abdominal pain may
occur. In some cases, there is intestinal
bleeding, leading to blood in the faeces.
The kidneys may become inflamed, resul-
ting in blood and protein in the urine.
The only treatment usually required is
bed rest and
analgesic drugs.
Complica-
tions may arise if kidney inflammation
persists. In severe cases,
corticosteroid
drugs
may be given.
heparin
An
anticoagulant drug
used to
prevent and treat abnormal
blood clot-
ting.
Heparin is given by injection and is
used as an immediate treatment for
deep vein thrombosis
or for
pulmonary
embolism.
Newly developed “low molec-
ular
weight
heparins”,
for
example
tinzaparin,
which need to be injected
once a day, are now widely used and
can be self-administered at home.
Adverse effects of heparin include rash,
aching bones, and abnormal bleeding
in different parts of the body. Long-term
use may cause
osteoporosis
.
hepatectomy, partial
Surgical removal
of part of the
liver
. Surgery may be need-
ed to remove a damaged area of liver
following injury, or to treat noncancer-
ous liver tumours and
hydatid disease
.
Rarely,
liver cancer
is treated in this way.
hepatectomy, total
Surgical removal of
the
liver
. Hepatectomy is the 1st stage
in a
liver transplant
operation.
hepatic
Relating to the
liver.
hepatitis
Inflammation of the
liver
, with
accompanying damage to liver cells. The
condition may be acute (see
hepatitis,
acute
) or chronic (see
hepatitis, chronic
)
and have various causes. (See also
hep-
atitis
A;
hepatitis B; hepatitis C; hepatitis
D; hepatitis E; hepatitis, viral.)
hepatitis A
Also known as epidemic
hepatitis
, this disorder is caused by the
hepatitis A virus, which is transmitted
to people in contaminated food or drink.
The incubation period lasts for 15-40
days, after which nausea, fever and
jaun-
dice
develop. Recovery usually occurs
within 3 weeks. Serious complications
are rare. Active
immunization
provides
the best protection against hepatitis A,
and an attack can confer immunity.
hepatitis, acute
Short-term inflamma-
tion of the
liver
, which usually recovers
in 1-2 months. In some cases, acute
hepatitis may progress to chronic hep-
atitis (see
hepatitis, chronic
)
,
but it
rarely leads to acute
liver failure.
Acute hepatitis is fairly common. The
most frequent cause is infection with one
of the hepatitis viruses (see
hepatitis,
viral
), but it can arise as a result of other
infections such as
cytomegalovirus
infec-
tion or
Legionnaires' disease.
It may also
occur as a result of overdose of
halothane
or
paracetamol
or exposure to toxic
chemicals including alcohol (see
liver
disease, alcoholic
). Symptoms range from
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