Scout leech link
g.read at niwa.co.nz
Sat Sep 20 01:08:47 EST 2003
The Scout Report ran a leech link this week in connection with human
ectoparasites as a topic, but this undated BBC story is actually from 1998,
deriving from a medical student's journal article which I tracked to:
Here's the Beeb's version.
Bloodsuckers hit the medical comeback trail
Leeches - the fleshy bloodsucking worms associated with the historic world of
medicine - are making a comeback - even if the yuk factor means they often
have to be hidden from public gaze.
A leech farm in Wales sells 15,000 leeches a year to the NHS, according to
London medical student Robert Weinkove, who has written a history of the worm
for the Student British Medical Journal.
Biopharm, a leech farm in Swansea, exports another 15,000 a year around the
Leeches were widely used up until this century for many medical conditions,
including tonsillitis and piles.
"They went too far, overusing them and using them in the wrong way with little
benefit, " said Mr Weinkove, a fifth-year medical student at the United
Medical and Dental Schools of Guy's and St Thomas' Hospitals in London.
A few doctors were still using leeches in the 1930s and 40s, mainly on stroke
patients, but their use died out until the 1960s when interest in the creature
But it is only in the last 10 to 15 years that they have really caught on and
their use has taken off in the last five years.
Mr Weinkove believes it has taken so long for them to come back because they
have an image problem.
"Doctors have been reluctant to use them because of their image, but now it
has been proven that they can be useful in certain cases," he said.
Leeches are particularly useful in plastic surgery, such as breast
reconstruction and where a part of the body has become severed and had to be
sewn back on.
Sometimes, the patient's veins are too weak to take the blood away from the
body part and the blood builds up, causing "venous congestion".
Attaching leeches to the body can draw the blood away gradually and painlessly
since leech saliva contains an anaesthetic.
This allows the re-attached body part to survive until the veins are strong
enough to work normally. One man who cut off his [use your imagination] had to
have leeches attached to drain the blood.
The leeches suck the blood until they become totally engorged. They can take
in up to 10 times their bodyweight in blood. When they are full they fall off
and can be replaced with another leech.
A patient may need up to 30 leeches to drain blood away.
Mr Weinkove says most patients are willing to have leeches on their bodies if
it is a choice between leeches, more operations or losing a part of the body.
He says children often give them names. But their family and friends are not
so keen to see the creatures at work.
This has led some doctors to hide the leeches, using dressings. Another
consideration is to ensure the leech feeds on the right part of the body.
Doctors in Philidelphia have developed a plastic shield to hide the leech and
keep it in place.
It involves a dinner plate-like object with a hole in it. This is used on
severed fingers. The patient's arm is covered in plaster of paris to keep it
raised in the air so the blood can be drained.
The dinner plate is put on top and the leech is attached and covered in
fabric. One of the doctors involved is called Dr Callegari, conjuring up
images of the famous German film.
Most hospitals in the UK which use leeches do not keep them on site when there
is no specific need for them.
There are a handful of pharmacies up and down the country which have storage
room for them. They can send leeches over to hospitals on request.
Leech saliva also has medicinal uses of its own. It prevents clotting and is
being used in several new drugs, for example, to treat patients who have had a
stroke, often due to blood clots in the brain.
A new one, hirudin, is being used in the US and may have less side effects
than other anti-clotting drugs.
Geoff Read <g.read at niwa.co.nz>
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