[at-l] New Tick bite concern

Carla & Dave Hicks carla_dave_hicks at verizon.net
Sat Jul 17 06:58:05 CDT 2010


http://www.roanoke.com/news/roanoke/wb/253939

>>>
The mystery of the tick and the allergy
Bedford's Emily Masters developed a sudden allergy to meat. So have many 
adults throughout the Southeast. Doctors set out to find the reason.
By Sarah Bruyn Jones | sarah.jones at roanoke.com | 981-3264


During the past two years more than 200 people at a regional allergy practice 
have been diagnosed with a newly identified red meat allergy that is related 
to tick bites.

This allergy may be responsible for up to half of recurrent anaphylaxis cases 
without known causes, researchers say.

In many ways the allergy doesn't behave like traditional food allergies, but 
it is causing people to feel sick to their stomachs, break out in hives and in 
some cases go into anaphylactic shock.

For Emily Masters of Bedford, the allergy seemed to come on without warning.

"I'm curious why all of a sudden this happened," Masters said. "I'm 28, so why 
have I been OK eating meat for so many years and then this happened?"

Masters was diagnosed after she had a severe reaction following last year's 
July Fourth cookout at her father's house.

During the party she ate some couscous, potato salad, hummus, a hamburger and 
a sausage. With a known wheat allergy, she said she was careful to avoid 
wheat, eating the burger without a bun for instance.

Several hours later her stomach started to hurt.

"I thought I must have eaten wheat that was hidden in something," she said.

But the reaction began to get worse than any reaction she had ever had to 
wheat.

Soon her arm began to itch just inside her elbow. She asked her husband to run 
to a nearby gas station to pick up some Benadryl.

He suggested she come along so she could take the medicine faster. By the time 
they were leaving she had hives on her legs. In the car, she began to swell 
and it became hard for her to breathe.

They called 911.

"By the time I got to the ambulance, I was a red lobster and looked like a 
blimp," she said.

Masters spent the night at Bedford Memorial Hospital being treated for 
anaphylaxis.

After she was discharged, she made up her mind to find out what caused the 
reaction. She asked her friends for the list of ingredients in the foods she 
ate. And she made an appointment at the Asthma and Allergy Center in Roanoke, 
where she had previously been treated for her wheat allergy.

"I freaked out and I'm assuming its some mystery food and I've never had this 
before," she said. "The last thing I imagined was it was beef."

While being examined, Dr. Luis Matos was brought in to consult. Matos has been 
among the chief specialists diagnosing patients with this new allergy. Matos 
and his partners in Roanoke and Lynchburg have diagnosed more than 200 cases 
since a researcher at the University of Virginia first discovered the allergy. 
In many cases, the patients don't have any other allergies, Matos said.

"It's so new that we don't know exactly the full story of how people develop 
this reaction and the history of the allergy," Matos said.

But as Matos has learned the symptoms of the allergy, he has quickly been able 
to identify patients.

"Just because we are looking for it, it is giving us an option that we didn't 
have before," Matos said. "It's similar to other new allergies -- once you 
know it is there, you find it."

The Asthma and Allergy Center also has identified patients who have had milder 
symptoms, such as chronic itching or vague intestinal problems, who test 
positive for the allergy. In some instances patients had gone decades without 
knowing the cause of their discomfort.

"They thought they were crazy," Matos said. "In some cases, they were told 
they were crazy."

Dr. Scott Commins of UVa is credited with discovering the allergy.

"In the world of food allergy, the notion that an adult could have a new onset 
food allergy is unheard of," Commins said during a recent interview.

Last week he was in Roanoke presenting his research to physicians at Carilion 
Roanoke Memorial Hospital. The hope is to alert more doctors to the research 
and the new diagnosis and how patients can be helped.

"I think you are seeing these patients and you may not know it," he told the 
doctors gathered for the presentation.

Since publishing his research in 2009, Commins said he has heard from patients 
and allergists throughout the Southeast. He gets multiple e-mails a day from 
patients looking for help.

Making the discovery

The home economics queen Martha Stewart has a small role in this story.

Researchers discovered some patients had a bad reaction after taking Erbritux, 
the anti-cancer drug at the center of the insider trading allegations against 
Stewart. Some of these patients would have anaphylaxis.

Researchers, who included Commins' boss Dr. Thomas Platts-Mills, ultimately 
showed the negative reactions to the drug were associated with an allergic 
reaction to a sugar called galactose-alpha-1,3-galactose, or alpha-gal for 
short.

A study about it was published in 2008 in the New England Journal of Medicine. 
Ultimately the drug manufacture changed the way Erbritux was made to stop the 
problem.

But because nearly all common allergies are reactions to proteins, not sugars, 
Commins said he was extremely interested in the discovery.

Areas in the Southeast appeared to be unusually hard-hit by the severe 
reactions to Erbritux, so Commins decided to investigate how common the 
alpha-gal reaction was among anaphylaxis patients where the cause was unknown. 
About 20 percent of anaphylaxis patients don't know the cause.

Alpha-gal is a sugar that is found in all mammals, such as pigs, deer and 
cows. Those who have an allergy to alpha-gal produce an antibody that binds to 
the alpha-gal sugar causing the body to produce hives or go into anaphylaxis, 
Commins explained.

A simple blood test will show if a person produces the antibody to alpha-gal.

Masters' blood test, which Matos sent to be tested by Commins, came back 
positive.

The connection to ticks

Figuring out why patients had suddenly developed a severe allergy to meats in 
which alpha-gal was present was the next step.

Commins quickly realized that the geographic range of the Lone Star tick 
matched the geographic location of people who had developed this allergy. Both 
were in the Southeast.

"It just fits perfectly," he said.

Commins started asking his patients about their exposure to tick bites and 
chiggers.

"A lot of science can be serendipity," he said. "My boss [Platts-Mills] goes 
out in the woods a lot. He got chigger bites or seed ticks. He developed this 
allergy. So we started to make the connection."

Masters too has had a lot of tick bites and chigger bites. Last year, prior to 
her July 4, 2009, reaction, she said she was bitten by about a dozen ticks and 
hundreds of chiggers.

Commins said outdoor enthusiasts, including hunters and hikers, are often the 
type of people diagnosed with the allergy. He strongly believes it is related 
to the seed tick bites that people get by the hundreds. These are the bites 
from the newly hatched tick larva, as opposed to a mature adult tick. Often, 
he said, people in this area call these tiny ticks chiggers.

It's unclear what in the seed ticks is causing people to develop the allergy.

"My honest gut feeling is it is something in the saliva," Commins said.

He said that unlike Lyme disease and Rocky Mountain spotted fever, he doesn't 
think it is an infectious disease carried by the seed tick. Instead he thinks 
something in the saliva triggers the antigens in the alpha-gal sugar.

He is developing new research to focus on the relationship to the insect.

Finding a cure

Masters said she misses eating a hamburger on occasion. Others, especially 
hunters, are more adamant about their desire to eat meat again, Commins said.

But for now, the only solution to treating the allergy is avoiding meat 
products. For Masters and many others, this includes avoiding foods made with 
beef broth.

"It's the hidden stuff that I worry about," Masters said.

Commins is planning a study to try to create a tolerance in patients. He's 
waiting on approval from an institutional review board that monitors studies 
involving people.

"Even though I don't really miss a big steak, a cure would be great, that way 
I wouldn't have to always worry when I get a twinge in my stomach or a little 
itch," Masters said. "I am always on edge wondering, 'What if it had beef or 
pork in it?' "

She always carries an epi-pen -- containing a dose of epinephrine to counter 
anaphylaxis -- just in case.

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