Spiders "wrongly" blamed
Thursday July 14th, 2011
Too many spiders are being blamed for unexplained flesh wounds, leading to patients getting wrong treatment, doctors warned today.
In
contrast the handiwork of a common biting spider, the Loxosceles, often
goes unrecognised, according to the analysis in The Lancet.
Doctors from Australia and Brazil say that spiders are often blamed for necrotic lesions - the death of tissue - but are rarely responsible for them.
More likely explanations are problems such as the infection MRSA or Lyme disease, they say.
There are about 41,000 known species of spider and most of them have bites which are harmless to humans.
However Loxosceles spiders cause a condition called loxoscelism. These spiders are found in warm countries around the world, including the Mediterranean, and are called by names such as recluse, fiddle-back and brown spider.
These are the only spiders proved to cause necrotic ulcers, according to Geoffrey Isbister from the University of Newcastle, New South Wales, Australia and Hui Wen Fan from Instituto Butantan, São Paulo, Brazil.
The doctors say antivenom treatments exist for many types of spider, including the Black Widow spider, which can poison humans, causing a condition known as latrodectism.
The doctors write: "Well designed clinical trials to test antivenom therapy in both latrodectism and loxoscelism need to be undertaken urgently.
"Such studies are needed to prevent the unnecessary use of ineffective antivenom, which puts patients at risk of allergic reactions, and to better define the timing and dose of antivenom when it is effective."
Tags: A&E | Australia | General Health | South America | Traveller Health | World Health
Printer friendly page