Angioneurotic oedema is a form of allergy,
mostly affecting young adults, that causes
severe local swelling of the skin, the lining
of the nose, the mouth, the throat or the
digestive tract. It is triggered by an insect
sting or by contact with certain foodstuffs,
plants, drugs or pollens. The swelling is
caused by a considerable accumulation of
fluid in the tissues and may persist for
hours or even days. The condition is also
known as angio-oedema, hives or giant urticaria.
The main danger arises
when angioneurotic oedema affects the voice
box (larynx). In this case the swelling
can rapidly lead to complete closure of
the airway, that can be life threatening.
Symptoms
A few minutes after
contact, the affected person becomes agitated
and flushed, and suffers palpitation, tingling
and itching of the skin, throbbing in the
ears, coughing and sneezing. Large weals
develop on the skin, and sometimes it is
hard to breathe because of swelling (Oedema)
of the lining of the larynx or tightening
of the air tubes in the lungs. If the main
effect is on the intestine, there will be
nausea, vomiting, abdominal pain and diarrhoea.
Causes
Some forms of the
disorder run in families and are due to
a gene defect. This mutation interferes
with the normal functioning of the immune
system so that a highly irritant substance
is produced. This acts on small blood vessels
in various parts of the body, causing them
to become leaky.
Treatment
Treatment is usually with
large doses of corticosteroid drugs or with
adrenaline. In cases in which a blockage
is threatening to close the airway and the
condition is not reversed by injection,
the only hope of saving life may be a tracheotomy.
This is a bold cut through the skin and
into the windpipe (trachea) just below the
Adam's apple, so as to make a new opening
to allow the affected person to breathe.
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Angioneurotic Oedema
