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Posts Tagged ‘true food allergy’

Accurate Diagnosis

Saturday, May 30th, 2009

The simplest and most certain test for any sensitivity reaction is to expose the person concerned to the substance under suspicion and see what happens. This is known as a

challenge test. With true allergies, challenge tests are powerful tools, but they are also alarmingly close to reality. The risk of provoking a severe reaction requires a very

cautious approach.
By comparison, an indirect test – a roundabout way of seeing how the body responds, such as the skin-prick test (see p. 91) – has the advantage of rarely producing dangerous

reactions. The downside is that indirect tests can be misleading, precisely because they are not like the real-life situation. No indirect test is perfect – there are always

false positives and false negatives (see box on p. 91).
Challenge tests
If you undergo a challenge test with food or an airborne allergen, you will also be given dummy challenges with an innocuous substance which is indistinguishable from the item

being tested. Neither you, nor the tester who is scoring the reaction, should know which is which. This is called a double-blind trial because, to eliminate all possible bias,

both of you are in the dark. (The full name is a ‘double-blind placebo-controlled trial’ – the dummy challenge is also called a ‘placebo challenge’ or ‘control challenge’.)
The double-blind trial is a standard medical procedure and does not imply that the doctors think you are faking symptoms. Psychological forces are powerful things, and just

thinking that you might react to a test can be enough to produce a reaction – the process that generates the symptoms is largely unconscious.
Food challenge
A food challenge – eating the food that is under suspicion – is a key test for food intolerance (see p. 197). It is sometimes used for food allergy and other forms of food

sensitivity too, as a follow-up to skin tests. Some allergists use a food challenge only if the skin test is at odds with actual events reported by the patient. Other allergists

use food challenge more readily, to confirm skin-test results, and to assess the severity of the reaction.
Extreme caution must be exercised with immediate food allergy, because of the considerable risks involved. The test must be done under medical supervision with resuscitation

equipment to hand. A challenge test should never be done for true food allergy without some careful preliminary tests on the face and the lips (see box on p. 23). Even if these

tests produce no reaction, only tiny amounts of the food should be eaten to begin with.
Bronchial challenge
This type of test involves inhalation of an airborne allergen – such as pollen – suspected of causing asthma. Bronchial challenge carries the risk of provoking a severe asthma

attack, and few doctors use it unless there are compelling reasons to do so – such as demonstrating that someone’s asthma is due to an allergen encountered at work.
Skin-prick tests
This is an indirect method of detecting true allergic reactions. It is one of a family of skin tests that use a similar approach. The three different tests in this family are

known as: skin-prick tests or prick tests, puncture tests, and scratch tests.
For the skin-prick test – the technique used in Britain – a small drop of liquid containing an allergen, such as grass pollen, is placed on the arm. The doctor makes a small

prick in the skin, under the drop of liquid, allowing a minuscule amount of the allergen to get into the skin. A positive reaction is recorded if a red bump develops soon

afterwards. For accuracy, the bump must be compared to positive and negative controls (see below).
The puncture method is very similar to the skin-prick test but uses a slightly different technique for breaking the skin. The term prick-puncture test covers both techniques.
With the scratch method, the skin is scratched lightly, and the allergen solution is then applied over the scratch. This method gives less consistent results than prick-puncture

testing.
It is important to include a negative control in the test – a skin-prick test with plain salt water (saline). This should not produce much of a bump – if it does, the skin is

clearly over-reactive and the tests more difficult to assess. The doctor should also include a positive control – a skin-prick test with histamine, the substance that plays a

central role in allergic reactions. This should always produce a bump. If it does not, the skin is decidedly under-reactive, and the tests are invalid.
Taking antihistamines will make the skin under-reactive, and you should stop taking them before the testing, for a period ranging from a day to several weeks – it varies

depending on the particular antihistamine. Ask your doctor for specific instructions about stopping these and other drugs before testing.
Skin tends to be over-reactive to testing in people with dermatographism (see p. 52). Blood tests for specific IgE,
such as RASTs (see p. 92), are needed for anyone who has this condition. Eczema sufferers with a rash over large areas of the body may also require blood tests, if there is too

little clear skin for testing.
Skin-prick tests can produce both false positives and false negatives (see box below). Some allergic diseases will give a lot of false negatives and relatively few false

positives, while for others the reverse is true. The allergen itself influences the rates of misleading reactions: for example, tests for soya allergy are notoriously

unreliable, whereas those for peanut are far more accurate. The age of the person being tested also makes a difference. With all these influences at work, interpreting the test

responses is a real art, and the doctor’s experience counts for a lot.
All sorts of people offer skin-prick tests, including alternative practitioners. Get them done by a qualified doctor, preferably by an allergist, who will know how to make sense

of the reactions.
Note that the purpose of these tests, and of blood tests for specific IgE, is to identify the allergens that are bringing on your symptoms, not to predict how strongly you will

react to those allergens. The tests may give some Indication of the intensity of your reaction, but they cannot be regarded as a good guide to how you will respond to the

allergen in the future.
The safety record of skin-prick tests is very good. Occasionally a systemic reaction (anaphylaxis) occurs with these tests, but there are no records of any deaths. Nevertheless,

if you suffer from severe asthma or have experienced anaphylactic shock in the past, it is advisable for the doctor to have adrenaline and resuscitation equipment available.

Those with strong allergic reactions to latex may also react badly if they are tested with an allergen that cross-reacts with latex (e.g. cypress pollen), not just when tested

with latex itself. Taking beta-Mockers (see box on p. 150) increases the risk of a life-threatening reaction for anyone in these higher-risk categories.
False positives and false negatives
Apart from challenge tests, none of the tests used for allergy works with 100% accuracy. Most give both false positives and false negatives.
A false positive means that there is a positive test but no actual reaction when the allergen is encountered (e.g. eaten or inhaled). A false negative means that there is a

negative test result despite a genuine reaction (as shown by a challenge test, for example).
A test that gives relatively few false positives has good positive predictive value – in other words, if it suggests you are allergic to something, you probably are.
A test that gives relatively few false negatives has good negative predictive value. If it comes up negative, you are probably not allergic to that allergen.
Some tests for allergic reactions show good positive predictive value but poor negative predictive value, while for other tests the reverse is true.

Alternative Ways of Allergy Treatment

Sunday, May 24th, 2009

When Leonard Noon reported his first tentative experiments with immunotherapy for hayfever, in 1911 (see p. 164), he believed that pollen contained a toxin. Most people were

‘immune’ to this toxin, he said, in the same way that people might be immune to measles or diphtheria, but hayfever sufferers lacked this immunity. Noon thought that his

steadily increasing doses of pollen, injected just under the skin, were inducing immunity to the pollen toxin, in the same way that a smallpox vaccine could induce immunity to

smallpox.
Noon’s theory was all wrong, as we now know, but the important thing was that the treatment seemed to work. In fact it transformed the lives of some patients, especially those

who were very severely affected by hayfever. One spoke of a ‘marvellous cure’, another of going for walks to kick my old enemy the hay’.
So doctors kept using Noon’s treatment, and in time — when it became clear that Noon’s theory was flawed — medical researchers began trying to figure out how the injections

really worked.
Surprisingly, they have still not succeeded, even though a great deal is now known about the changes that can occur in people undergoing immunotherapy. Despite a wealth of

detailed knowledge (see p. 166), it remains impossible to say exactly how conventional immunotherapy reduces allergic reactions. Surprising discoveries about the effects of

conventional immunotherapy are being made all the time.
New methods of immunotherapy are still being devised today, and there are three different approaches being taken.
Firstly, there are doctors experimenting with modifications of the technique devised by Noon. For example, instead of injecting the allergen extract, some doctors are giving it

to their patients in capsule form. to be swallowed. Others are giving it as a liquid, to be placed under the tongue and held there for a few minutes, then swallowed (see p.

169). Sound scientific trials show that both these methods work well, at least with some allergens.
There are also experiments with speeded-up immunotherapy
(see p. 166), called ultrarush techniques — at the outset, injections are given at hourly intervals, or even more frequently (in hospital, of course, where severe reactions can

be dealt with immediately). Doctors have found that they can induce a remarkably rapid tolerance of the allergen in this way.
The second approach is to apply modern medical knowledge about allergic reactions and so develop entirely new methods of immunotherapy (see p. 168-9). Such research involves

working out, from first principles, novel ways of modifying the immune response in general, or the reaction to one allergen in particular.
This theory-led approach is certainly successful for classical allergies such as hayfever and perennial allergic rhinitis, where there is a good understanding of the basic

mechanism (i.e. the malfunctions of the immune system that produce the disease). But for those diseases where the underlying mechanism is only partially understood, such as

atopic eczema, this approach is not necessarily the best one. And for diseases such as food intolerance, where the cause of the illness remains largely unknown, it is a complete

non-starter.
The third type of approach is to devise a technique by trial and error, and then puzzle out the ‘how’ question later. This is the same sort of path as Noon originally took, and

some believe that this kind of pragmatic experimental approach — practising a method which seems to be effective, even though it’s a mystery how it works — is as valid now as it

was in 1911. Others disagree.
210 complementary therapies The two most widely used methods that have been developed in this way are Provocation-Neutralisation and Enzyme- Potentiated Desensitisation.

Although these techniques are practised by doctors with a conventional medical training, they remain ‘outside the pale’ as far as orthodox medicine is concerned. The

controversies that surround them are discussed below.
Enzyme- Potentiated Desensitisation (EPD)
This technique has been developed by a British doctor, Dr Len McEwen, who began work on it in the 1960s. It is now practised in many parts of the world, as well as Britain,

including the United States, Germany and Italy.
EPD is used for a far wider range of problems than conventional immunotherapy, being given to people with food intolerance and chemical intolerance, as well as to those with

true allergies. This — along with the fact that it is unclear how it works —contributes to the controversies that surround it, because these conditions do not have the same

basic causes.
Dr McEwen began with the observation that, when immune cells are aroused during inflammation — whether caused by allergy or some other stimulus — they release large amounts of

an enzyme called beta-glucuronidase. This enzyme increases the immune response to the allergen or antigen that provoked the inflammation.
Dr McEwen experimented with injecting beta-glucuronidase into the skin, along with very small amounts of allergen, believing that in such circumstances the enzyme might have the

opposite effect, and reduce the immune reaction to the allergen. Eventually he discovered a combination of enzyme and allergen which seemed to have the desired effect.
EPD has been tested, in a rigorous scientific manner, and the results suggest that it can work for hayfever and asthma, as well as for childhood migraine and hyperactivity in

children when these are triggered by foods.
In one trial with hayfever patients, researchers measured the levels of anti-pollen IgE following EPD treatment, and it did not rise during the pollen season as it normally does

in those with hayfever. This kind of finding is impressive because it is unlikely to be due to placebo effect. Not all studies have produced positive results, however.
In addition, doctors using EPD claim that it is very effective for patients with allergies who have not done well on the standard course of immunotherapy injections (see p.

164). This fits in with other studies suggesting that the immune changes brought about by EPD are fundamentally different from those induced by traditional immunotherapy.
Patients with true food allergy have been given EPD, and while it does not enable them to eat their culprit food, it does
seem to reduce their reaction to accidental exposures.
Doctors in the Netherlands are using EPD as a treatment for people with Chronic Fatigue Syndrome (CFS), and report that it helps about 50% of patients.
One point in favour of EPD is that it uses very small amounts of allergen, and is therefore very safe — anaphylaxis has never occurred with this technique.
Provocation-Neutralisation
‘After following conventional methods [of immunotherapy] for thirteen years, I heard Carleton H. Lee deliver a paper on provocative testing in 1965, at a meeting of the American

College of Allergists in Chicago. I was naturally sceptical, but tried his suggestions when I returned to my office. The results can only be described as astounding. Many

patients with unresolved allergic problems responded markedly and rapidly. Many with resistant asthma or perennial allergic rhinitis improved greatly or cleared completely when

food injection therapy was added to their inhalant injection therapy.’ So wrote Dr Joseph B. Miller — a distinguished allergist and paediatrician, and a Professor of Medicine at

the University of Alabama, in 1972.
The technique which he learned from Carleton H. Lee was controversial then and, although Miller developed it with great care and precision during the years that followed, it

remains controversial now.
There are two elements in provocation - neutralisation: testing and treatment. Both are used for a wide range of problems — not just classical allergic diseases, but also food

intolerance and chemical intolerance. As with EPD (see left), this is one of the controversial aspects of the technique.
Although provocation-neutralisation involves an injection technique that looks, superficially, very much like conventional immunotherapy (see p. 164), there are several

important differences. Firstly, the allergen extract used (in the case of true allergies) is a very dilute extract, so that far less of the allergen is injected than in

conventional immunotherapy. Likewise, in the case of food intolerance and chemical intolerance, the extracts of the offending substance are used in highly dilute form.
Secondly, the idea of the neutralising dose — which is the central plank of provocation-neutralisation — is quite different from anything in conventional immunotherapy. Broadly

speaking, the conventional technique (see pp. 165-6) works by slowly reeducating the immune system with a gradually increasing dose of the allergen. Only after a succession of

injections does the immune system start to behave differently on encountering the allergen. By contrast, in provocation-neutralisation treatment, the neutralising dose is

claimed to have an instantaneous and direct effect on the body, ‘turning off’ symptoms that have already begun. This is the neutralisation aspect of the technique. The doctors

who practise this technique do not claim to know how the neutralising dose might work.
According to the theory of provocation-neutralisation, the strength of the extract that acts as a neutralising dose is specific for a particular allergen and a particular

person. It can only be worked out by a rather slow procedure involving a series of injections. These are intradermal injections – they place the allergen extract in the skin, at

a slightly deeper level than a skin-prick test. (For treatment, rather than testing, subcutaneous injections are used – these go deeper than intradermal injections, placing the

allergen extract just underneath the skin. Neither hurts very much.)
Ideally, the neutralising dose should be decided on by measuring the size of the wheal (a raised area of skin around the injection site), and whether it grows, stays the same

size, or disappears. The doctor or nurse carrying out the procedure can, in theory, work out the neutralising dose just by careful examination of the skin wheals.
However, it is part of the tradition of provocation-neutralisation techniques that verbal feedback from the patient is also taken into account – so if the patient says that an

injection has turned off the symptoms, that reinforces the belief that the neutralising dose has been found.
The problem with this aspect of provocation-neutralisation is that expectations, and the power of suggestion, can become involved. So if the doctor or nurse says ‘you may find

that this next injection makes the symptoms go away’, that is often exactly what happens – because the forces of placebo effect (see p. 233) come into play. Unfortunately,

verbal interactions such as this are a key aspect of the provocation-neutralisation procedure in many clinics.
Just the same hazard besets provocation - neutralisation if it is used to test for the existence of allergy or intolerance, because it is quite common for practitioners to tell

patients which allergen (or other offending substance) is being injected and to ask if any symptoms are provoked by the injection. This is not good practice – if someone expects

to react to a particular substance, they are quite likely to produce symptoms through purely psychological mechanisms (see pp. 232-3).
Quite apart from this, the question of allergy testing with provocation-neutralisation techniques is contentious, because the pioneers of the technique, such as Professor

Miller, never advocated using provocation - neutralisation in this way. Using it as a routine test for sensitivity reactions was a later development, and there are many doctors

today who, while they practise provocation-neutralisation as a treatment, say that it does not work well as a test for sensitivity reactions. While they agree that injecting a

dose
which is either stronger or weaker than the neutralising dose may provoke actual symptoms (this is the provocation aspect of the technique) they don’t think the reaction is

reliable enough to form the basis of a test for allergies. Nor do they think that using skin-wheal measurements alone (i.e. silent testing) turns the technique into an accurate

test for allergies. That is not what the provocation-neutralisation technique was designed for – it is about treatment, not testing.
The evidence from research
Recent research from the Nova Scotia Environmental Health Centre in Canada confirms that testing by provocation injections is not reliable. The subjects in this study were all

suffering fr= multiple chemical intolerance, a condition which – for one reasor or another – makes patients liable to develop symptoms at an,, time. No less than 70% of these

patients experienced symptoms in response to a dummy injection which contained none of the offending substance. Indeed, 15% of patients also produced a skin wheal in response to

some of the dummy injections, confirming that even this reaction may be subject to the power of suggestion (see pp. 232-3).
Looking just at the patients who did not react to the placebo injection (i.e. those least susceptible to suggestion) the test still did not yield any reliable result – a person

might react to one injection with a particular substance, but fail to react to a subsequent injection with the same substance. The authors concluded that their patients were ‘in

a state of heightened sensitivity as the result of the chronic irritation by various environmental components and other external and internal stressors’. In this state of

sensitivity. patients are so close to the brink all the time that the smallest thing can trigger symptoms. So the apparent reactions to the test injections were actually

determined by other factors – some psychological factors (including a psychological response to the prick of the needle) and some external ones, such as exposure to smells or

very small amounts of airborne chemicals.
Another recent research study, carried out by scientists at the University of California, confirmed the finding of the Nova Scotia team as regards testing. Although this study

did not set out to look at the use of the neutralising dose for treatment, some of the patients were given neutralising doses during the testing process and the researchers

observed that ‘in most cases a single neutralising injection relieved the symptoms’. This casual observation clearly needs to be confirmed by more rigorous testing. Oddly

enough, despite this positive observation about the neutralising doses, the overall conclusion of the researchers was to completely dismiss all aspects of

provocation-neutralisation as ‘the result of suggestion and chance’. This conclusion has been widely publicised in the United States as part of a general campaign against

provocation-neutralisation and doctors who practise it.
Other researchers have looked at treatment with neutralising doses, using stringent scientific methods (a double-blind placebo-controlled trial — see p. 90), and found that they

do work. In one such trial, patients with asthma. and allergies to dogs or cats, were treated with injections of the neutralising dose. They showed a reduction in the

sensitivity of their airways, as measured by objective tests. In another experiment, patients with perennial allergic rhinitis and an allergy to house-dust mite were studied,

and the neutralising dose was given as drops of allergen extract placed under the tongue (sublingual drops) – an alternative to injections. The blockage of the nose, as measured

by scientific tests, was reduced by the neutralising dose.
A great many more trials of this kind would be required to convince most doctors that provocation-neutralisation works.
Furthermore, the recent study from California – which observed a number of practitioners of provocation-neutralisation at work with their patients — showed that these

practitioners need to be a lot more rigorous and objective in their approach. However, the fact that provocation-neutralisation is often practised badly does not necessarily

mean that the basic technique is without any value. There are a great many level-headed doctors and patients who, while initially very sceptical about

provocation-neutralisation, have found it surprisingly effective – just as Professor Miller did back in 1965.
Deciding for yourself
So is provocation-neutralisation an option that is worth trying for your condition?
As regards testing, the answer is probably ‘no’. The most reliable tests are skin-prick tests or FAST blood tests for true allergies (see pp. 91-2), an elimination diet for food

intolerance (see p. 194), and avoidance followed by re-exposure (a challenge test) for chemical intolerance.
As regards treatment for true allergies, conventional immunotherapy has been far more thoroughly tested and, if you can get it (not easy in Britain — see p. 164), is probably a

better bet. It is definitely the best treatment for allergy to insect stings.
The major advantage that provocation-neutralisation has over conventional immunotherapy, in the case of true allergies, is that it is far safer. Because such small amounts of

allergen are used, anaphylactic reactions (see p. 58) don’t occur.
When it comes to treatment for food intolerance, complete avoidance of the problem food(s), for a period of a year or two, is usually a very effective treatment (see p. 77).

Other forms of treatment are only needed for people who find that they have
intolerance to a great many different foods (on the basis of an elimination diet, not kinesiology, blood tests and the like — see p. 93) and cannot devise an adequate diet from

the foods they are able to eat. For such people, provocation-neutralisation may be worth a try. Many patients feel that they have gained considerable help from this treatment.

They report suffering fewer symptoms and being able to return to a more nutritionally balanced diet.
In the case of chemical intolerance, the first line of treatment should be to avoid the substances concerned as far as possible, eat a good balanced diet, and take a vitamin and

mineral supplement if nutritional deficiencies are suspected. Treating any underlying hyperventilation (see pp. 226-9) can also help considerably. Only if there are persistent

symptoms, and you are sure these are not due to psychological causes, might provocation-neutralisation be worth a try. Some people with chemical intolerance do find it is

helpful, but whether this is a real effect, or simply placebo, remains uncertain.
If you decide to give provocation-neutralisation a try, find a practitioner who has good medical qualifications, who seems objective and sensible in their approach, and who

doesn’t make implausible claims for the technique. Take note of what other treatments the practitioner offers, and whether these seem rational or not – this is often a good

guide to the care and objectivity with which provocation - neutralisation is carried out.
Ask the doctor how he or she assesses the neutralising dose. and avoid anyone who does not use the traditional method of a series of injections combined with wheal measurement.

When the neutralising dose is being assessed, say that you would like it to be done ’single-blind’ – that is, you don’t want to be told anything about what is being injected.

Reporting how you feel to the doctor or nurse during the assessment is fine, but only mention really significant symptoms, or a very definite clearance of the symptoms, if this

occurs. These precautions will help you to be sure that you are getting something which is of genuine benefit, rather than just a very expensive form of placebo treatment.
I always wanted to be a doctor, and I enjoyed
medical school immensely, but once I became a
ell GP, I no longer felt quite so sure about what I was doing. It seemed clear to me that there were a lot of people coming to my surgery who I couldn’t do much for. And there

were others who, while I could treat their obvious medical problems with some success, remained distressed and were not coping well with life. Once I became a senior partner in

this practice, I experimented with having a counsellor come in for one session a week, and then an osteopath for the bad backs. It was popular with the patients, and I saw some

people improve enormously. Now we have stress-management classes too, and one of my colleagues has trained in acupuncture, which he uses for selected patients. We also use

elimination diets for patients with a lot of long-term problems like migraine. Overall, I think of it in terms of having more tools at our disposal - being able to tackle things

from a different angle when standard medicine isn’t hitting the spot.’
Geoffrey, a GP in the north of England, is typical of the reconciliation that is now beginning to occur between conventional medicine and alternative medicine. But he also has

plenty of criticisms to make of the alternative scene. ‘The idea that alternative medicine is “holistic” while conventional medicine isn’t, really raises my hackles. Most GPs

could be magnificently holistic if they had an hour with each patient as alternative therapists usually do. We have just 15 minutes, on average, and we have to pack a lot into

that - including our basic duty to eliminate the possibility of serious organic disease such as cancer. Time pressure is everything now, and it has squeezed the humanity out of

medicine, to a very large extent. But the potential for a holistic approach is there - most doctors have a tremendous store of wisdom and life
experience at their disposal, which could form the basis of a holistic approach to treatment if only there were more time to spend with each patient.’
It is in search of a more unhurried and all-embracing approach to treatment that many people turn to alternative medicine. Frequently, what they get out of the therapy has less

to do with the actual methods used, and still less with the theories behind those methods, but everything to do with spending a quiet hour with someone supportive and caring who

listens to all the complex concerns that surround any illness, gives reassurance or advice, or just offers a `safe space’ in which to talk about life’s difficulties.
Other people turn to alternative therapies due to a more serious disillusionment with orthodox medicine. When patients with inscrutable medical problems -such as persistent

unexplained diarrhoea, joint pain or chronic urticaria - are given a succession of different diagnoses by different doctors, they often lose faith entirely in modern medicine

and reject orthodox treatment in favour of alternatives. This is a great mistake. Modern medicine isn’t perfect, but that is only to be expected, because it is not a fixed body

of knowledge but a process - a continuing journey of questioning, investigation, discovery and improvement. Scientific medicine has come a tremendously long way from the state

of ignorance that prevailed two centuries ago, and it will undoubtedly go farther.
Conventional medicine has a great deal going for it - ask anyone over 50, with severe life-long asthma, what they think of treatment now compared to treatment in the 1950s or

early 1960s. You will hear a hymn of praise to the improvements in both drugs and drug delivery systems. Asthma is just one example -conventional medicine has a lot to offer for

all the classical allergic diseases. Alternative medicine should always be regarded as an adjunct to conventional treatment, not a replacement. That is why many doctors prefer

the term complementary medicine.
A third reason for using alternative medicine is a more philosophical one, a need to understand illness in some larger sense, often part of a general search for meaning in life.

Some types of alternative treatment attempt to offer metaphysical reasons for allergy -rather than the mundane explanations of antibodies and immune cells that are given in this

book - and this can be attractive to some people. There is no harm in this approach, which can prompt you to make a critical review of your life, look at unresolved emotional

issues, or reassess choices that are making you unhappy.
But not all illness, or worsening symptoms, can be explained by emotional causes, and the rigid belief that every illness must have a meaning can be damaging. It easily

degenerates into the wholesale psychologisation of illness, the kind of blame-the-victim mentality which can attribute hayfever to ‘Emotional congestion; fear of the calendar; a

belief in persecution; guilt’ and asthma in babies to ‘Fear of life; not wanting to be here’. Both these diagnoses are taken from the best-selling You
can Heal your Life by Louise Hay, which is very influential among some alternative therapists. This compulsive psychologisation of illness can be profoundly damaging, and if

your complementary therapist is preoccupied by ideas of this kind, you could find yourself on a very long guilt trip indeed.
Apart from the psychological aspects of alternative medicine, there is the question of whether it actually works in a practical sense - whether it provides more than just

emotional support and placebo effect (the benefit that comes from any treatment which you believe in). This is always the central question for scientific medicine in relation to

its own treatments,
and conventional doctors naturally apply the same criteria to alternative medicine. Most of this chapter is concerned with trying to answer that question.
Unfortunately, there are so many different kinds of alternative therapy available today that it is impossible to cover all of them in this book. To complicate matters further,

many complementary therapists now practise two or more different techniques, mixing them to
produce their own unique cocktail of diagnosis and treatment. This eclectic approach can span a remarkable range - you may find a therapist doing distinctly whacky stuff such as

iridology (looking at the eye to diagnose all illness - it has been tested and definitely doesn’t work), combined with something perfectly rational such as an elimination diet.

(The elimination diet might be presented as a ‘detox diet’, but it is actually being used to detect food intolerances.)
With new forms of therapy springing up all over the place, a healthy scepticism is a distinct asset for the consumer. Be sceptical about any diagnostic test or treatment that is

only being practised by one person in the country, or in the world - when doctors hit on something that works, they want other doctors to try it out. World exclusives in

medicine are usually suspect.
Avoid any practitioner who tells you to stop using your drugs without your doctor’s consent. Likewise, avoid those with a messianic gleam in their eye, an evident disregard for

logic or reasonable discussion, or an amazing cure that fixes everything from acne to AIDS. Very few of those who sell bogus cures and phoney diagnostic tests are complete

rogues. Most are nice people who are quite genuinely convinced that they have indeed found the answer to people’s problems. The powers of placebo effect (see p. 233) can sustain

such a conviction for a very long time.

Allergens in Food

Friday, May 22nd, 2009

Allergens in Food
Anyone with true food allergy or coeliac disease needs to be very careful about avoiding certain foods. The information given here is aimed mainly at such people, rather than those with food intolerance (see p. 74), who can usually tolerate small amounts of their offending foods. However, some of the basic information given here is relevant to those with food intolerance as well.
There are different levels of sensitivity even among those with true food allergy. The ‘exquisitely sensitive’ can react to unbelievably minute traces of the food, and for them life is especially difficult. The same is true of some coelicacs, who can be affected by the tiniest quantity of gluten.
These people are a small minority. The level of vigilance required of such people will not be necessary for most people reading this book, so don’t get things out of proportion. While it is vital to be sensible about avoiding your problem food, it is also important not to become over-anxious.
Buying basic ingredients
Cooking for yourself is the safest way to eat for those with true food allergy and coeliac disease. There are relatively few hazards, but do beware of well-meaning assistants in health-food shops who try to sell you some exotic package of grain or flour – spelt or kamut or triticale, for example – reassuring
you that it is ‘definitely not wheat’. Be well informed about the different forms of your problem food and the names under which it is sold (see pp. 172-5).
Oils made from foods such as corn or peanut sometimes cause concern. Ordinary refined oils have been so thoroughly processed that they actually contain no allergenic proteins, so you can safely use these. Bottles of gourmet walnut oil and almond oil are a different story however, and should be avoided if you have nut allergies. Sesame oil is not purified either and can provoke serious reactions. With any oil, if you are unsure how safe it might be, go by the smell. Oils that smell or taste like the food from which they are made could well contain allergens.
Those with allergy to tuna can usually eat tinned tuna because the processing makes it safe. The allergens in fresh fruit and vegetables are generally inactivated by cooking too, so jams and tinned fruits tend to be safe – but test very cautiously. Cooking does not have much effect on other food allergens, apart from eggs. In rare cases, cooking can create allergens (see box on p. 186).
If you share your kitchen with others, and are highly sensitive, check that all cooking utensils are truly clean before use. Coeliac should watch out for breadcrumbs in the butter dish, jam or toaster. Where small children are allergic to a food, it may be best to keep the culprit out of the house entirely.
Genetic engineering and food allergy
Many people with food allergies are very concerned about the possibility that genetic engineering could introduce allergens from one plant species into another. This concern seems to be shared by government officials and those in the food industry, who are being extremely vigilant and cautious at present. As long as this attitude continues, there should be little danger to food allergy sufferers.
Finding food in funny places
If you are suffering some inexplicable reactions to non-food items, it might, just possibly, be a food reaction. Some latex gloves contain the milk protein casein, for example, added as a manufacturing aid.
Buying packaged foods
There are several different issues here:
• the need to read labels carefully for allergenic ingredients described by unfamiliar names (see p. 172)
• errors in the packaging used (see pp. 174-5)
• contamination by minute traces of a food substance due to processing machinery not being cleaned adequately. Cartons of fruit drink have occasionally been contaminated with traces of milk because the same production lines were used for packaging milk drinks. Tofu desserts made in ice-cream factories can also become contaminated with milk. These tiny traces of a food will only affect the most highly sensitive individuals, but contamination by nuts can involve large pieces and affect anyone with nut allergy (see p. 174).
• foodstuffs which are used as part of the production process
and leave a tiny residue in the finished item (see p. 174).
Be very cautious indeed about ready-made food that is unlabelled, such as that from bakeries and home-made stalls. Egg is frequently used as a glaze on baked products, nuts may lurk within, and milk or wheat can turn up in the most unlikely places.
Restaurants, cafes and takeaways
The majority of fatal and near-fatal incidents involving people with true food allergy are due to restaurants, cafeterias and canteens. Takeaways can also be a problem except in the case of the large chains such as McDonald’s, where ingredients are standardised. It is alarming that highly allergenic foods (e.g. peanut) are sometimes used – yet far from obvious – in recipes and sandwich fillings where they would simply not be expected. Anyone with peanut or shellfish allergy should be ultra-cautious about Chinese, Thai or Malaysian cooking – but those with milk allergy should find a haven here, because milk is not part of these culinary traditions.
The simplest solution is to eat very plainly when you go out –steak and salad, for example. Steer clear of casseroles and thick soups, where you can’t see what’s in it (the occasional chef throws in peanut butter to thicken the mix…). Food wrapped in pastry is best avoided for the same reason. Desserts and cakes are risky for anyone with nut, egg or milk allergy.
You must insist on accurate information about the food before you taste it. If the counter staff, the waiter or the waitress
is unsure of the ingredients, ask them to check with the chef, or with the label on pre-packaged food. Be persistent and never eat anything unless you are sure. Make eye contact with the person concerned, and learn to be a good judge of character. Your life could depend on telling the difference between the waiter who knows the facts about the food and the waiter who is being blandly reassuring for the sake of a quiet life.
It is a great mistake to pick out the pieces of offending food – kiwi fruit from a fruit salad for example – and eat the rest. There is often enough allergen left behind to cause anaphylaxis in the highly allergic individual.
Those who are extremely sensitive to the offending food must also consider the problem of contamination in the kitchen. Grills and fryers in restaurants and canteens can become contaminated with fish allergens or nut allergens (e.g. from nut cutlets) and these can be transferred to fried potatoes or other foods, provoking anaphylaxis in the highly allergic individual. One person with fish allergy died in this way. Sesame seeds can also contaminate equipment, work-surfaces or bakery counters.
Parties and buffets
Milk, egg, shellfish or nut allergies can make it especially hazardous to eat buffet or party food. Regard everything with suspicion. Cocktail snacks with nuts or peanut paste hidden inside are a particular problem.
When fish allergy isn’t fish allergy
Anisakis is a parasitic worm that infests fish and can sometimes survive the
cooking process to infect humans. The worms are easily thrown off by the human immune system, but the body is primed to make IgE antibodies should
it ever encounter Anisakis again. Another meal of parasitised fish – even if the Anisakis worms are all dead this time, and only the allergens remain
will provoke a massive IgE-mediated reaction, leading to anaphylactic shock. This problem is usually misdiagnosed as allergy to fish itself.
Other inconsistent reactions to food can be due to contaminants such as antibiotics, preservatives, other food additives or (especially in the case of shellfish) naturally occuring toxins.

Immune reactions to food

Tuesday, May 19th, 2009

Immune reactions to food
`When I finally found someone who could say what was wrong with me, it was such a relief. I can’t tell you how much ill-health and pain and misery I’d had up to that point. I’m immensely grateful to the doctor who sorted the problem out for me. My life has been transformed.’
Richard has eosinophilic gastroenteritis, one of the rarer immune reactions to food. Like all rare diseases, it can escape diagnosis for a long time. IgE (the allergy antibody – see box on p. 12) is sometimes involved in eosinophilic gastroenteritis, but it is not an essential part of the reaction. Those who, like Richard, do not make IgE antibodies to the problem food will not give positive skin-prick tests. For them, the possibility of food being responsible for their symptoms may well be overlooked*.
Another difficulty for patients such as Richard is that most of the non-IgE immune reactions to food affect babies and children exclusively. A few of them can also occur in adults, but this is very rare, so it’s not something that automatically springs to mind when the doctor is searching for a diagnosis.
Eosinophilic diseases
The key event in these diseases is the arrival of large numbers of immune cells called eosinophils (see p. 19) in the walls of the digestive system. If the eosinophils converge on the tube leading down to the stomach (the oesophagus) the disease is called eosinophilic oesophagitis, and the symptoms include reflux (regurgitation) of food, occasional vomiting, refusing food (in babies), stomach pain and disturbed sleep.
If the stomach is the focus for the eosinophils, this is eosinophilic gastritis, and there is vomiting, pain, poor appetite and therefore poor growth. There can also be obstruction of the stomach outlet which may, in a few babies, produce pyloric stenosis (the main symptom is projectile vomiting).
When eosinophils flock to the intestines as well as to the stomach, the disease is called eosinophilic gastroenteritis. In
terms of symptoms, the picture is not much different from the previous condition, but there can be diarrhoea as an additional symptom, and babies may be irritable and puffy in appearance.
These conditions are most common in babies, but sometimes they continue through childhood. Very occasionally they occur in adults too.
Heiner’s Syndrome
This disease affects babies only, and is very rare. It is a severe form of cow’s milk sensitivity leading to wheezing and haemosiderosis (bleeding into the lungs). The child usually seems sickly, growth is slow, and there may be recurrent bouts of pneumonia. A full diagnosis requires blood tests to check for anaemia, examination of sputum under the microscope, and a biopsy or lavage (see p. 92) from the lung. The only effective treatment is to remove cow’s milk from the diet completely. Needless to say, this must be done under full medical supervision.
Other reactions to food
The cause of these diseases is not fully understood, but the immune system is clearly involved.
Dietary protein entero-colitis syndrome
In babies, the symptoms begin with general irritability and vomiting between one and three hours after a feed. Unless the offending food – usually cow’s milk – is withdrawn promptly, there will be bloating, diarrhoea (usually containing blood), anaemia, and poor growth. Older children have similar symptoms, while adults suffer terrible nausea, plus stomach pains and vomiting.
Nickel in food
Nickel and other metals in food may cause immune reactions for those with sensitivity to such metals (see pp. 55-6). The symptoms are usually in the skin, but there can be a few digestive symptoms too.
Dietary protein enteropathy
The main symptom here is diarrhoea, usually very severe. Often babies vomit their feed as well. Most have little appetite, and if the offending food is not withdrawn they suffer from poor growth, anaemia and other signs of malnutrition. This is because damage to the lining of the gut prevents nutrients from being absorbed properly. Older children show similar symptoms.
Dietary protein proctitis
This is a far less severe problem. The babies with this disorder look healthy, but there is inflammation in the bowel and small amounts of blood are passed with the faeces.
Diagnosis
There are two aspects to diagnosis:
• what kind of disease is it?
• what food or foods are causing the reaction?
Your doctor will probably try to answer the first question by looking inside the digestive tract with special equipment (endoscopy) and by taking a small sample – a biopsy (see p. 92).
A blood sample may also be taken to look for raised levels of immune cells and antibodies. Skin-prick tests or RAST tests (see pp. 91-2) will be tried to rule out the possibility of true food allergy – and because IgE may play a small part in these other forms of food sensitivity (in the eosinophilic diseases, for example).
Often the tests yield no very clear answers, especially in babies, and an exact diagnosis is not possible. But failure to answer the first question does not mean that the second question should be ignored. Pinpointing the culprit food or foods is vital.
Identifying the food is easier the younger the child, simply because the range of foods eaten is so much smaller. Cow’s milk is the most common offender when the disease affects young children – particularly bottle-fed babies, since standard infant formula is made with cow’s milk. Your doctor will prescribe an alternative formula (see box on p. 66) for you to try. For older children and adults, an elimination diet will probably be required to identify the food concerned. Among young children, likely offenders include soya, egg, wheat, rice, chicken or fish. A simple elimination diet, similar to that used for atopic eczema (see p. 198) may be adequate. You must have full medical supervision for this.
In the case of eosinophilic reactions, skin-prick tests may help identify the foods concerned, but are usually of limited value, so an elimination diet is again necessary. Where adults are affected by eosinophilic diseases, sensitivity to several different foods is likely, so identifying the offending foods usually requires the most exacting form of elimination diet, using an elemental diet for the exclusion phase (see box on p. 196). The symptoms are very slow to disappear: it can take up to eight weeks of avoiding the foods before your ailing digestive tract recovers. Don’t give up too soon.
Treatment
Avoidance is the only way here. Special infant formula (see box on p. 66) is required for cow’s milk sensitivity in babies.
In the case of eosinophilic reactions, some doctors may use steroid tablets as an additional treatment, just for a few weeks, to get the inflammation under control. Some new studies show that the anti-leukotriene drugs (see p. 149) are very effective for eosinophilic gastroenteritis.
Controversial topics
According to some doctors, a reaction to food may, on rare occasions, produce vasculitis (inflammation of the blood vessels).
Vasculitis itself is a well-recognised condition. The blood vessels are damaged by inflammation, and become more leaky. Symptoms often begin with a general swelling (angioedema), and an outbreak of small red blotches deep in the skin — especially on the legs — where small amounts of blood have escaped. These blotches later turn purplish, then yellow, before fading. This type of rash is known as purpura. Sometimes there are larger emissions of blood, resulting in spontaneous bruising.
Many different conditions can cause vasculitis, but only a few doctors would agree that food sensitivity is one of them. The inflammation could be caused by circulating immune complexes containing food antigens bound to antibodies (see p. 13). There is evidence, in some patients, of a direct effect on the cells called platelets that cause blood to clot.
Equally controversial is the suggestion that food sensitivity can be the cause of trouble for some children with kidney disorders. Some research groups have found that a few children with certain kinds of kidney disease recover on an elemental diet (see box on p. 196). All those affected have a classical allergic disease such as asthma or atopic eczema as well, and they tend to be sensitive to several different foods, plus pollen or other airborne allergens. Circulating immune complexes might be involved here, but no one is sure.
Some cases of food-related rheumatoid arthritis and palindromic rheumatism (see p. 76) could be due to immune complexes involving food molecules becoming deposited in the joints, but it is not the mechanism in all, or even most, of those affected.

FOOD SENSITIVITY IN ASTHMA, ECZEMA AND OTHER ALLERGIC DISEASES

Monday, May 18th, 2009

FOOD SENSITIVITY IN ASTHMA, ECZEMA AND OTHER ALLERGIC DISEASES
In 1995, medical researchers in North Carolina, USA, asked over a hundred dermatologists how they treated atopic eczema. All used standard treatments such as moisturisers and steroid creams, but only 14% mentioned the possible role of food to the parents of children with eczema.
Between them, the dermatologists in this study treated about 17,000 children with atopic eczema per year. Using the most widely accepted estimates for food sensitivity in atopic eczema –38% of eczematous children are sensitive to food – one can calculate that there were over 5000 children in this study area who might perhaps have benefited from avoiding a problem food, but whose parents were never told about this treatment option.
North Carolina is by no means unique. The situation is much the same in other parts of the world, which adds up to millions of children and parents not even being told about a treatment that is frequently effective.
Other allergic diseases (see right) can also be triggered by food, although the percentage of patients affected is much lower than for atopic eczema. Here too, many doctors are unaware of (or sceptical about) the possible role of food.
These reactions are best described as ‘food sensitivity’. They cannot be called food allergy (see p. 62) if there are no symptoms in the mouth or gut and if skin-prick tests are negative – as is often the case. Negative skin tests suggest that the reaction is not IgEmediated (see box on p. 12).
However, in some children with atopic eczema. the skin-prick tests to culprit foods are positive. When these foods are eaten after a period of avoidance, such children sometimes suffer an
immediate reaction, with symptoms typical of true food allergy. For these individuals, their atopic eczema seems to be a symptom of IgE-mediated food allergy.
How can an atopic eczema reaction in response to food be IgE-mediated in one individual and not in another? Research is finally beginning to answer this question (see pp. 18-19).
The allergic conditions that may sometimes be induced, or simply aggravated, by a non-immediate reaction to food are:
• atopic eczema (atopic dermatitis)
• asthma
• perennial allergic rhinitis (constantly blocked or runny nose)
• chronic sinusitis
• secretory otitis media (’glue ear’).
In all of these conditions, many other causes exist. Except in the case of eczema, the other causes are far more likely than sensitivity to food. This fact will weigh heavily with your doctor, whose instinct, quite sensibly, is to look for likely causes first.
Taking asthma as an example, food sensitivity is relatively unusual as a primary cause, whereas allergy to airborne items. such as pollen or house-dust mite, is very common. Food probably affects only 8-10% of asthmatics overall, but is much more important for those with brittle asthma (the most severe and unstable form), affecting as many as 60% in a recent study.
The pollen connection
People who suffer from both birch-pollen allergy and atopic eczema may have worsening eczema when they eat certain fruits and vegetables, e.g. apples and carrots. These same foods cause Oral Allergy Syndrome (see box on p. 63) in some with birch-pollen hayfever, but they can aggravate eczema without causing Oral Allergy Syndrome.
Diagnosis
Consider other likely allergens first. Look at p. 28 for the airborne allergens that could play a part in perennial allergic rhinitis, chronic sinusitis, secretory otitis media (’glue ear’), and asthma. Only in the case of children with atopic eczema is food a prime suspect (between 38% and 69% of children with atopic eczema are affected by food), but even here there are a lot of other factors to consider (see pp. 43-4).
If you do decide to investigate the role of food, don’t abandon basic treatments in the meantime. By neglecting these. you could make the whole problem a great deal worse.
There are various clues that food is at fault:
• If you have other symptoms that suggest food intolerance (see p. 76). These problems often seem to go together with food-induced asthma or rhinitis.
• If you have noticed that a particular food makes your symptoms worse. Where there is intolerance to one food, there could well be intolerance to another, which you have not noticed.
• If you have exercise-induced asthma (see p. 41) and sometimes respond severely to exercise but sometimes have little or no reaction. Sensitivity to a food or foods may be instrumental in changing the response to exercise.
• If you have brittle asthma – but you must get your doctor’s consent for an elimination diet. Foods must be tested under medical supervision as severe life- threatening asthmatic reactions can occur on testing.
• If there are also digestive problems such as diarrhoea, vomiting or belching. This is a strong clue in the case of children with atopic eczema. Symptoms such as diarrhoea frequently precede atopic eczema, and it seems likely that a reaction to food in the gut increases the leakiness of the gut wall, allowing more food molecules through to the blood.
• If there is pronounced eczema around the mouth in children (but this can also be due to constant licking),
• For adults with atopic eczema, if there is a persistent rash on the hands, or the lips. Where there is a blistering rash on the hands that erupts at regular intervals, food is often the problem – or it may be metal contaminants of food such as nickel (see pp. 55-6). In general, food sensitivity is rarer among adults with atopic eczema than it is among children.
Skin-prick tests (see p. 91) for commonly eaten foods are worth
trying in all the diseases – if they give a positive result, they should
be noted, but if they give a negative one, they should be disre-
garded. The many alternative tests being marketed (see p. 93) are
highly inaccurate and unlikely to help.
Research from Tampere University Hospital in Finland suggests that babies are much more likely to give false-negative skin-prick tests for food than older children and adults with atopic eczema. The Finnish researchers found that 52% of babies with atopic eczema give a negative skin-prick test despite having a genuine reaction when tested by food challenge. In an attempt to tackle this problem, they have devised a patch test, similar to those used for contact dermatitis. The patch test, in which food is applied to intact skin and left there for two days, gives false negatives in only 39% of babies.
The best way to detect food-sensitive eczema, according to Dr Erika Isolauri. who heads the Finnish research team, is to use both tests, and take note of a positive reaction to either. This detects 80-90% of eczema-causing food reactions in infants.
Few other doctors are currently using patch tests for atopic eczema; because so much controversy surrounds this topic, and no standardised method has yet been devised. You may be lucky and find a specialist who does these tests.
To confirm the role of particular foods in atopic eczema, a food challenge test is essential, having first avoided the food carefully for two weeks. Great care is needed in testing (see p. 198).
If you cannot get suitable tests done. a simple elimination diet will be needed (see p. 198).
Treatment
There is a choice here, between avoiding the offending food, or eating normally and controlling the symptoms with drugs.
The difficulty comes when parents have to make this decision on behalf of their children. Unfortunately, there is insufficient evidence as regards the consequences of this decision. Treating food sensitivity can reduce the eczema symptoms substantially in the short term, but it does not necessarily improve the long-term prospects for the child. Orthodox doctors tend to think that eating a normal diet is much better for a child nutritionally and socially, and they have a point.
Doctors with a special interest in food sensitivity generally believe that treating the problem at source, rather than just suppressing the symptoms with drugs, must take the pressure off the child’s immune system, and give the child a better chance of growing out of sensitivity reactions in the long run.
The decision is yours – but it is vital that the diet is not more of an encumbrance than the disease itself, and that the child’s interests come first (see pp. 170-71). Whatever you do, don’t allow a child to become malnourished (see p. 198).