The American brown recluse spider, seen here, is cousin to the pesky Mediterranean recluse. The Mediterranean recluse looks very similar but has distinctive genitalia and eyes.
One woman's Italian vacation took a turn for the worse when she woke up with pain in her ear one night. She had no way of knowing then that she'd just been bitten by a Mediterranean recluse spider, and that a chunk of her ear would soon be liquefied by the spider's venom. But that's exactly what happened, according to a recent report of her case.
The 22-year-old woman soon sought treatment for her pain in an Italian hospital, where doctors prescribed an antihistamine. But the swelling in her face and pain in her ear didn't get any better. Once she was back home in the Netherlands, the ear got worse, and portions of it turned black — a clear sign that the skin and cartilage cells were dead.
The dead tissue made it clear to doctors that the woman had been bitten by a Mediterranean recluse, a spider whose bite is known to destroy skin and underlying fat, causing "sunken-in" scars or "a disfigured ear, if you are very unlucky," said Dr. Marieke van Wijk, a plastic surgeon in the Netherlands involved in the woman's treatment.
This is the ear after the dead tissue was removed.
The case is the first evidence that recluse-spider venom can also destroy ear cartilage, said van Wijk, a co-author of the case report, published last month in the Journal of Plastic, Reconstructive & Aesthetic Surgery.
Venom from recluse spiders, including the American brown recluse and its Mediterranean cousin, kills skin and fat with a mixture of chemicals, including substances that break down proteins. The complex nature of the venom makes the bites hard to treat, van Wijk said. A drug called Dapsone has been used, but there is no proof that it works to treat these bites, she added.
Therefore, the recommended treatments for these spider bites are icepacks and painkillers, van Wijk told LiveScience.
In this case, van Wijk and her colleagues removed the dead tissue, and recreated it using cartilage from the woman's ribs.
Recluse spiders rarely bite people, and when they do, the bites don't usually inflict serious damage or large scars. Most bites occur when people roll over onto a spider while asleep, or when they put their foot into a shoe in which a recluse is found. It's difficult to diagnose a brown-recluse-spider bite, and many suspected bites actually come from stinging insects, or are caused by other things, such as bacterial infections.
The spiders are "not that dangerous," van Wijk said. "I wouldn't take precautions, but if one develops a mysterious red-white-and-blue and swollen lesion in summer, in an endemic region, keep the brown recluse in mind," she added.
In a small minority of cases of recluse bites, the venom can cause a severe immune reaction that destroys blood cells. A recent study found that a drug used to treat unrelated rare blood disorders, eculizumab, may be able to reduce the destruction of blood cells in these patients by 80 percent.
First published November 18 2013, 9:16 AM