Archive for March 25th, 2009


Wednesday, March 25th, 2009

Doctors have at their disposal a variety of ways to test for allergy. But trying to get a consensus of opinion on which allergy tests are the best is like trying to find out which car is the ‘best’. Everybody has their own preference. For instance, some doctors say that the RAST test (a type of blood test) is the ‘best’ way to test for food allergy and that skin tests are the worst. Others say just the opposite. But whatever test your doctor uses, it’s important to realize that all allergy tests have shortcomings and that no matter what the results, you still must pay close attention to your diet and environment to help your doctor diagnose allergy correctly.

Traditionally, skin tests have been the techniques of allergy diagnosis. Here are several methods of skin testing.

1. Placing a drop of allergen extract (a diluted amount of the suspected substance) on the skin and scratching the surface of the skin (scratch test).

2. Pushing the test substance into the skin with a needlelike probe (prick or puncture test).

3. Injecting the test substance between layers of skin (intradermal or intracutaneous test).

When the allergen makes contact with the skin, mast cells release histamine and other allergy-inducing substances, which usually produce a ‘weal-and-flare’ reaction within ten to fifteen minutes if the test is positive. (If the test is negative nothing happens.) The raised weal, or welt, may vary in size from that of a mosquito bite to that of a large thumbnail; flare is simply another word for redness. To distinguish between irritation at being stuck with a sharp metal object and a genuinely allergic reaction, a separate test dose of plain salt water is applied also.

The scratch test is the least sensitive but the safest of the three skin tests, since the material can be wiped off if a severe reaction is unexpectedly triggered. And the scratch test is the least painful, although no one looks forward to any kind of skin test. (Children, especially, tend to fuss at encounters with needles.) Injected material, on the other hand, cannot be removed, but it most accurately reflects the allergic tendency, picking up levels of sensitivity so low that they often do not produce any symptoms.

The puncture test is basically a version of the intradermal test; once the fluid has been placed in the puncture hole, it essentially has been injected. And the puncture test is only slightly less sensitive than an intradermal test, without the added risk and discomfort. So unless your doctor can give you a good reason for choosing a scratch or intradermal test, the puncture test is the most preferable of the three skin tests.

None of these skin tests, however, is 100 per cent foolproof. In fact, the irony of skin tests is that they’re more accurate for people who suffer immediate, severe reactions – people who probably already know what they’re allergic to. They’re not as useful for diagnosing the cause of hives or eczema as they are for diagnosing the cause of asthma, hay fever or other classic allergy symptoms.

What’s more, skin tests can only be used to test for allergy to certain things. Except for penicillin, skin tests are not useful for diagnosing drug allergy. And even when skin tests for penicillin allergy are used, the only people to get tested are those who have a known allergy to penicillin but must take the drug for a serious infection. The only other use for a drug skin test is to establish the safety of egg-derived vaccine in children who have a history of egg, chicken or feather sensitivity.

As for detecting allergy to stinging insects, skin tests are notoriously poor. They’re also fairly unreliable when it comes to food allergy. For instance, a person may have a ‘positive’ skin test for egg, but if he can eat eggs with no problem the test is meaningless; for all intents and purposes, no allergy to egg exists. (A ‘positive’ test means a person has the allergy; a ‘negative’ test means there’s no allergy.)

In the case of pollen or dust, skin tests are not 100 per cent accurate. So the real proof is in the breathing.



Wednesday, March 25th, 2009

Many different medical disorders can cause aching or swelling in your muscles, including bone problems, too much exercise without proper conditioning or too little exercise, says Dr William G. Crook, an allergist in Jackson, Tennessee. ‘But still another cause of musculoskeletal discomfort is allergy.’

‘Almost all patients with extensive food allergy complain of muscular aching,’ says Frederic Speer, a professor of pediatrics at both the University of Kansas and the University of Missouri, and director of the Speer Allergy Clinic in Shawnee Mission, Kansas. ‘The most commonly affected muscles are in the neck, upper back and [arms and legs].’

In fact, food allergy is a common but often overlooked explanation for ‘growing pains’ in children. An allergic youngster may complain that his legs ache even though his posture is good and he doesn’t have flat feet,’ says Dr Crook.

One of Dr Crook’s patients was an eleven-year-old girl with sore neck and shoulder muscles, who also had frequent bouts of wry neck (muscle contractions along the portion of the spine that runs through the neck). Various doctors had incorrectly diagnosed her problem as everything from arthritis to rheumatic fever. Eventually, her muscle aches disappeared completely when she simply eliminated corn from her diet.

Allergy-related muscle aches can also accompany hay fever, eczema, headaches, stomach problems or other forms of allergy. You may not associate your soreness with allergy at all. Yet when allergies are brought under control, the muscle aches may disappear.

For instance, an allergy doctor reports the case of a thirty-four-year-old man who had muscular pain in his neck and shoulders for fifteen years. He also had other symptoms typical of allergy, such as post-nasal drip. Tests showed that he was allergic to several foods. After he stayed away from milk, wheat, fruit, artificial flavorings and condiments for two months, his pain went away completely.

Dust, pollen, chemicals or other airborne allergens can also cause muscle aches. If you always wake up achy in the morning, you could be allergic to mattress dust, in which case using a mattress cover and thoroughly vacuuming the mattress will help. If you feel achy after a night of partying, alcohol or cigarette smoke could be at fault. And if your muscle aches are at their worst during spring, summer and fall, pollen allergy could be to blame.

Such was the case reported by an allergy doctor of a twenty-five-year-old woman whose arms, shoulders, neck, upper back and chest were sore. She suffered all year, but ached more than ever in spring, summer and autumn. Skin tests showed that she was allergic to several grass and tree pollens. Allergy injections for pollen wiped out all her symptoms.

In people with generalized muscular aches, allergy control relieves not only muscle soreness – it relieves the worry that they’re neurotic or hypochondriacs, imagining soreness that has no real cause. Relief gives them peace of body and peace of mind.



Wednesday, March 25th, 2009

To a great extent, relief also depends on how well you can avoid airborne allergens. In fact, the first thing most allergy doctors usually tell their hay fever patients is: ‘Avoid whatever bothers you.’ But that advice is only useful if you’re also told exactly how to avoid the problem. You can install an air filter in your bedroom, however. Giving yourself eight solid hours of breathable air every night goes a long way towards round-the-clock relief. For some people, flicking on an air filter has been known to relieve hay fever misery in as little as ten minutes.

Another way to ‘filter’ pollen is to rinse your hair and change your clothes and shoes the minute you come in from working or playing outdoors. This helps to shed pollen grains that would tend to stir up symptoms if allowed to stay on your clothes.

Reducing your exposure to other common hay fever triggers – such as dust and moulds – can be just as simple. For instance, switching from a conventional bag-type vacuum cleaner to a more efficient and thorough water-trap vacuum cleaner will help you to get all the dust out of a room. And hooking up a dehumidifier (the kind you can buy in any department store) in the basement or bathroom cuts down on growth of moulds and mildew.

The odours of aerosol air fresheners and other household cleaning products can also aggravate your hay fever. Substituting simple, less noxious cleaning agents for complex chemical products cuts down on indoor air pollution and can leave you breathing more freely after just a day or two. You can follow as few or as many recommendations as you see fit, depending on what sets off your hay fever. Most people, however, notice a big improvement after making just a few of the basic changes we suggest.

One last suggestion: if you smoke, try to quit. Smoking irritates the respiratory tract and will only aggravate your already beleaguered nose and airways. In fact, Stuart Freyer, an ear-nose-and-throat specialist in Bennington, Vermont, told us, ‘Smoking is madness for anyone who suffers from hay fever.’



Wednesday, March 25th, 2009

A bruise is a purple splotch on the skin caused by broken and bleeding blood vessels underneath the surface. Bruises usually result from unexpected clashes with sharp corners or from other forceful encounters.

Some people bruise at a loving tap, though. Or they frequently wake up with unexplained bruises. Their bruises seem to appear for no reason. Spontaneous bruises are no serious threat to health, yet they’re embarrassing – and puzzling.

Could a bruise be a blood vessel’s way of reacting to an allergen? Very possibly, says Dr William J. Rea, a cardiovascular surgeon in Dallas, Texas. For one thing, blood vessels are fifteen times more sensitive to certain environmental chemicals such as formaldehyde and pesticides than are other tissues of the body. And in the course of treating several people for phlebitis (inflammation of the blood vessels, usually in the leg), Dr Rea noticed two things. All of the people with phlebitis were spontaneous bruisers, and when they were admitted to a chemical-free ‘environmental control unit’ of his hospital, their phlebitis cleared up and they no longer bruised as easily (Annals of Allergy). So Dr Rea proposes that in some people, bruising is part of a reaction to chemicals coursing through their blood vessels.

‘I’ve seen at least a hundred bruises that were caused by environmental allergy,’ Dr Rea told us.



Wednesday, March 25th, 2009

Even if you take supplements, a sound diet of wisely selected, nutritious food is critical to successful allergy control. First of all, if your diet is in any way limited because of food allergies, there’s simply no room remaining for nutrient-poor foods. Secondly, snacks and other processed or convenience foods are more likely to quarter hidden offenders than straightforward, wholesome fare. More broadly, however, allergies of any kind demand all the goodness and nutrition you can muster from your diet so that you bolster total health. It’s much like proper car maintenance: the best tune-up in the world won’t make your car run well if you’re still pumping low-grade petrol.

Dr Robert W. Boxer, an allergist in Chicago, told us, ‘I give everyone who walks into this office a list of foods to avoid – coffee (including decaffeinated), soft drinks, beverages with chemical additives and preservatives, chocolate, sweets, biscuits, cake, pastries, refined sugar (beet or cane), bleached white flour and some brands of ice cream. I tell them, “I don’t think these foods are good for you. They have no nutritional value – or very little – and they may hurt you. So, in my opinion, you should stay away from them. Your allergies will bother you less. You’ll have more resistance to toxins in your environment.”

‘I tell that to every patient, and I’ve been doing it for many years,’ says Dr Boxer. ‘I don’t expect them to stay off junk food totally, because they won’t be able to. But to the extent that they can, they should.’

One way to cut down on nutritionally poor food is to stop eating snacks or desserts that you don’t really want. Casual and almost constant nibbling – reaching for a food just for the sake of something to do – does more harm than an occasional full-scale binge.

You may find that cutting down on junk foods comes easily and naturally. For people who are serious about controlling their allergies, good nutrition appears to be one more solid stepping stone to total relief.