NASHVILLE — An increase in spider-bite patients at Vanderbilt University Medical Center here has created some concern — but not about an influx of brown recluse spiders in garages, attics or bathroom cabinets.
The problem is people using home remedies to try to reduce the swelling and the pain, said Dr. Donna Seger, medical director of the Tennessee Poison Center and a Vanderbilt professor.
Ointments don't work; neither does a coffee-ground poultice, she said. Just keep the lesion clean and dry, and put ice on any welt to help curb the pain because pain pills won't work.
"The ones that have problems are the ones that get infected," Seger said. "I've seen these pictures on the Internet that aren't representative of what really is out there."
The notion of poisonous spiders that live in people's houses creates a hysteria even in places that aren't brown-recluse habitat. Brown recluse spiders are found in much of Alabama, Arkansas, Kansas, Kentucky, Louisiana, Mississippi, Missouri, Oklahoma and Tennessee as well as parts of Florida, Georgia, Illinois, Indiana, Iowa, Ohio and Texas, according to Mike Potter an extension entomologist at the University of Kentucky College of Agriculture.
People say they have seen them far outside their usual territory, he wrote. But while the spiders can hitch a ride in belongings in a moving van, they generally don't establish new colonies.
Seger has been seeing two to four bite patients referred to her Middle Tennessee center each week vs. one every couple of weeks last year, a number that varies each year like snake bites.
"This shouldn't be this, 'Oh, my God, the spiders are coming,' " she said. "The difference between two and four is not like going from 200 to 400."
While brown recluse spiders are numerous, they also are, well, reclusive.
If they wander indoors from woodpiles, piles or rocks or leaves, they'll probably retreat to a dark closet or perhaps a shoe, according to the Centers for Disease Control and Prevention. They don't spin webs like other poisonous spiders including black widows and hobos, and if you see them walking about at night, they are looking for insects for a meal.
These spiders — sometimes called violin or fiddleback spiders because of their markings — can't bite humans without somehow being trapped, even inadvertently, against the skin, according to the CDC, which doesn't keep statistics on the number of brown recluse bites each year.
People can avoid the potential for bites by moving beds away from curtains or walls, according to a University of Tennessee Extension Service fact sheet. Another good idea: Shake clothing or shoes before putting them on.
Most of the bites create a blister or red area that will heal on its own from the inside out if you keep the area clean and dry, Seger said. Those are cutaneous bites that can take a long time to heal, painful but not a big problem.
Less frequently, brown recluse spider bites can create a systemic problem — a fever, rash and general discomfort that a doctor should check out. If those symptoms are accompanied by blood in the urine, a symptom of a red-blood-cell breakdown called hemolysis, the spider's toxin can be life threatening and a transfusion is necessary, she said.
Seger said she sees that more often in children than adults.
"If you have a child with a rash, fever and dark urine, you need to get him to an emergency room," she said. "If you have a child with a bite that's hurting, you don't need to do anything" but monitor the situation, keep the wound clean and put ice on the area to tamp down the pain.
Doctors don't have a test that can diagnose whether a particular welt is a brown recluse spider bite, she said. Physicians will refer patients to her because they're not sure, and she's seen enough of them to know what the bites look like.
"This isn't like pneumonia that doctors see all the time," Seger said. "This is relatively rare."