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A Broad
Introduction to Concept of Allergic Diseases
The introduction
describes how any body system can be affected, and how
the most important clues to the cause or causes of any
problem usually found in the patient’s story. The skill
of the investigator lies in recognising important
statements, and following them up to form a pattern.
Specialisation has resulted in barriers between clinics
for chest, ear nose and throat, skin, and so on, so that
some unfortunate patients attend several clinics when
there should be one allergy clinic for all allergic
problems.
Both public and doctors have become obsessed with”
tests”, often believing that sending away blood, hair,
or faeces will result in a diagnosis by return. For
allergies this is often a fallacy, because a positive
result means little unless the doctor can make sense of
the result, and a negative test result does not exclude
intolerance because there are no tests for intolerance
to foods, except avoidance to see what happens. It is
much quicker to get blood taken than to take a history,
especially as it is unusual for a doctor to know the
right questions to ask or to recognise significant
answers, because doctors are so seldom taught anything
about allergy in Medical School.
Food Intolerance differs because there are no reliable
tests, leading to difficulties in diagnosis.
Manipulating the diet is necessary for diagnosis and
treatment, and several foods may be involved.
A Global
Diagram is presented to show how different organs of the
body can be affected, and that an allergy specialist
must consider the human body as a whole, not just each
of the parts in isolation. |
Introduction
This website is dedicated to the millions of British allergy
sufferers who have great difficulty in obtaining expert advice
regarding their problems. One reason is that the subject has been so
rarely taught in British medical schools that most doctors know very
little about allergies.
Paradoxically, Scientific Allergy Research
in this country is renowned world-wide, but is mainly targeted at
finding out what happens in an allergic reaction, and discovering
how to stop or control it. Generous support is given by the
pharmaceutical industry, hoping to find a way to completely suppress
all allergic reactions without side-effects or any need to find the
cause of the problem. “Breakthroughs” in research often hit the
headlines, but it is not sufficiently realised that even if such a
discovery were to be announced tomorrow there would still be many,
many years of clinical trials before the remedy could come into
general use. Hopes that a potential panacea to cure all has been
discovered are often dashed, but the disappointing news seldom gets
the publicity which was given to its discovery.
Meanwhile, Clinical Allergy, which involves the investigation and
management of a wide range of allergic diseases and reactions, has
been so seriously neglected that there is now only one allergy
specialist for every three million people in the UK, and large parts of the country
have none at all. There are only eight centres of excellence for
allergy in Britain, so we could be said to have the most inadequate
allergy service in Europe.
Allergic reactions can affect any part of the body, therefore a
clinical allergist should have very wide interests extending to all
body systems. This generalised feature of allergic diseases is often
not appreciated by other specialists, especially in recent years
since the boundaries between specialties have become more and more
strictly defined and developed. For example, very few British
paediatricians are knowledgeable about allergy, yet their wards are
crowded with asthmatic children who seldom have their allergies
properly investigated, and most British skin specialists do not
appear to accept the importance of allergy as a cause of eczema.
The Allergy Epidemic
Two hundred years ago allergies were very uncommon, but have become
more and more prevalent in developed countries, especially in the
last fifty years. In 1997 a European White Paper was published, which
declared Allergic Diseases to be a Public Health Problem in Europe
which is so large that it should be called the First Epidemic of the
21st Century, but Britain took little or no notice. It is
undoubtedly true that Allergies of all kinds have increased to the
extent that over a quarter of the population in all developed
nations is now predisposed to develop allergic problems. This
increase in allergies has coincided with global changes, such as the
industrial revolution, increased pollution of air and water, and
huge changes in the diet and environment with the adoption of
western life-styles.
For example, since pasteurisation and refrigeration made possible
the production of huge amounts of milk, almost everybody has some
milk products every day of their lives. More recently central
heating, double glazing, and fitted carpets have provided the ideal
habitat for the dust mites, the major environmental cause of asthma
and rhinitis. Our environment has also been contaminated with
myriads of new chemicals, food colourings, preservatives,
pesticides, and drugs to which man has never been exposed before.
Furthermore, over recent years there has been a serious and
progressive decline in the quantities of trace minerals in the soil
which are essential for the health of all plants. In their turn,
these trace minerals are essential for the health of both man and
beast, who eat the meat and vegetables. This decline in essential
minerals has been so drastic that it may be a factor in the increase
in allergic diseases.
It seems reasonable to suggest that these enormous environmental and
dietary changes must have strained the human capacity for adaptation
to the limit. In consequence more and more of us fail to adapt to
these changes in food and environment which, in an evolutionary
sense, have occurred comparatively rapidly. As a result, a minority
have reacted against these changes in an abnormal, excessive, and
self-destructive manner by developing allergies, which might better
referred to as Diseases of Defective Adaptation to the Environment.
These considerations also apply to coronary disease, hypertension,
and diabetes, because all these diseases have increased rapidly
within a few decades, whenever Western life-styles and diets have
been adopted by developing third world countries. It is undoubtedly
true that many people dig their graves with their teeth!
Heredity is also very important because if neither parent has an
allergy the chance of a child being allergic is only 5-15%, and if
one parent is allergic about 25%. But if both parents are allergic
50-70% of the children are likely to have allergies. People from
allergic families often have positive skin reactions and sometimes
positive blood tests to environmental allergens as well, yet they
have no allergic symptoms. To be sensitised without symptoms is
called “atopy”, and these people are called “atopic” because they
have a strong tendency to develop allergic diseases if they are
over-exposed to allergens, as when renovating an old house and being
exposed to lots of dust. They resemble a loaded gun, which will not
go off unless the trigger is pulled.
Why I have used the “Anecdotal” Approach in this Website
This website is exceptional, because the infinitely variable
presentations of allergic disease are illustrated by case-histories
and photographs from my files, which are undoubtedly more memorable
and interesting than purely scientific reports. These date back many
years during which I have sometimes had the privilege of observing
children with allergic problems grow up, get married, and raise
families who also have allergies. Some readers might even identify
with an unusual story which might suggest a possible answer to their
problems in a way that cold statistics could never achieve. I have
also tried to express my personal opinions regarding clinical
allergy as clearly as possible, and I leave it to the reader,
whether medically qualified or not, to decide if these concepts and
experiences are significant or otherwise.
It is fashionable in medical circles today to disparage and dismiss
interesting observations and individual case-reports as being
‘anecdotal’, and therefore of little or no significance. This is to
ignore the fact that the recognition of many diseases began by
studying individual patients, relying entirely on case-history,
clinical findings, and accurate observation, confirmed many years
later by the development of scientific tests. Acceptance of a new
pattern of illness, or “syndrome”, can be seriously hindered by the
lack of a diagnostic laboratory test. The interactive and
time-consuming taking of a case-history is becoming a neglected art
today, yet our patients all have meaningful stories to tell if
anyone will listen and try to interpret them. To rely purely on
laboratory diagnosis is to regard patients as being like animals and
unable to communicate.
Allergic patients are a very individualised group of people, who
complain of a wide variety of symptoms caused by an infinite range
of possibilities, so that they are very difficult to sort into tidy
groups. It is often said that 'there’s now’t so queer as folk', but
allergic folk can be the queerest of all!!!!! These individual
case-histories refer to one individual’s problems and their
solution, and will not mean much unless the reader has some
knowledge of the broad principles underlying the causation of
allergic disease. For this reason it is suggested that the
introductory section with the Global Diagram be read carefully
before looking at the individual sections.
The World Wide Web gives me the opportunity to share my experiences
with colleagues interested in Clinical Allergy, which is truly the
Cinderella of all the Medical Specialities. Large sections refer to
hitherto unpublished researches which might interest colleagues as
well as those plagued with allergies. Many individual case-histories
are detailed which led to successful advice or treatment when
allergy or intolerance had not been suspected, but these stories can
only be regarded as pointers suggesting a possible cause.
Statistically significant data, evidence based medicine, and
‘meta-analyses’ of published research papers are rightly the current
gold standards of conventional medicine, but allergic diseases are
so infinitely variable and individualised that they often do not fit
into any rigid classification. For example ’Meta-analysis’ is a
statistical ‘audit’ of all published papers or clinical trials on a
specific subject. First of all the papers to be reviewed are
selected using rigid criteria which always exclude all trials which
were not double blind and placebo controlled,. This selection
process can seriously affect the result and reach a totally wrong
conclusion. A good example is a meta-analysis which found no
evidence of benefit from any method of controlling dust mites, which
was published in the British Medical Journal in spite of the fact
that this conclusion is obvious nonsense.
Current methods used in clinical trials are ill-suited to allergic
disease, where each patient is very much an individual with specific
personal problems. For example the effects of treating a patient, or
of treating their environment with an agent to kill the mites, can
be effectively assessed In clinical practice by comparing their
disease state before and after the intervention, using all available
objective methods such as peak flow rates in asthma, measuring
precisely the amount of dust mite in house dust, and subjective
symptom diaries. In short, by using the patient as his or her own
control the results will soon indicate whether a treatment is
effective or otherwise. Unfortunately nowadays this time-honoured
method of assessment of a therapy has become quite unacceptable and,
at the present time (2010), clinical trials have become beset by distrust
and often strangled with red tape.
There are already many websites which give helpful information and
advice about allergies, so I have not attempted to be comprehensive.
To write a website about allergy has been a daunting task which I
felt unable to undertake until I was fortunate enough to initially
obtain expert help in Web design from Alex and Alastair Campbell of
Surescreen Ltd. Derby, followed by a complete website redesign in
2011 by Graeme Storey, of Force 10 in Scotland.
Please note that this website is for information and interest only,
and is not intended as medical advice or advice on treatment. I
cannot be held responsible for any actions that anyone might take as
a result of reading the information in this web-site. I am
particularly concerned that nobody should adhere to a restrictive
diet for more than about three weeks, and that medical advice should
be obtained before dietary manipulation.
The
'Global' Concept of Allergic Disease
To illustrate how allergy can cause such a wide range of problems I
have constructed a diagram to demonstrate how the whole body, or
only parts of it, will react to the ‘allergen’, the name for the
cause of an allergy. When the ’allergen’ is inhaled, ingested, or
contacted, a reaction will occur only in the part of the body which
has become sensitised. For example ingesting a food to which the
subject is allergic may cause a reaction in the gut itself causing
rejection by diarrhoea or vomiting, or be absorbed into the blood to
reach other sensitised parts. The result depends on how sensitive
the allergic part of the body may be, how much allergen has entered
the blood, and whether the reaction is fast or slow. For example,
when the whole body is very sensitive, life-threatening anaphylaxis
occurs on exposure to the allergen because everything reacts
at the same time.
The symptoms depend on which part of the body is sensitised to the
allergen. An allergen inhaled with the air we must breathe, such as
pollen in summer or dust mites all year round, will produce hay
fever if the nose is the sensitised area, asthma if the bronchial
tubes are sensitised, or both simultaneously. This reaction happens
rapidly on contact with the lining of the respiratory system, but
sometimes the respiratory system does not become sensitised, and the
allergen gets into the blood to reach the sensitised skin, causing
eczema. Direct contact from outside the body may also cause eczema
by entering the skin through invisible cracks.
The Global Diagram - The Key to Understanding Allergic Disease
The Difference between Food Allergy and Food Intolerance
Food allergy is when eating a tiny amount of a specific food causes
an obvious reaction anywhere in the body. When a reaction takes
place all over the body at the same time, this is acute anaphylaxis,
the most dangerous manifestation of allergy. What has happened is
that an antibody called IgE has been developed towards a specific
food and is circulating in the blood. Its presence can be detected
in the blood by the RAST test, an immunological test carried out in
a laboratory.
This IgE antibody sticks to the surface of special
allergy cells called ‘mast’ cells, which are to be found in the
lining of the blood vessels, the bronchi, the nose, the eyes, and
all over the body in the skin. The mast cells in the skin are
responsible for producing specific reactions to skin testing which
indicate the causative allergens.
When tiny amounts of food are
absorbed from the gut into the blood, as shown in the Global
Diagram, they finally reach the IgE antibody on the surface of these
primed mast cells. This triggers them to disintegrate and set free a
variety of nasty chemicals into the body fluids, one of which is
histamine. It is these chemicals, usually referred to as ‘mediators’,
that cause the allergic reaction to take place. Various drugs, such
as antihistamines, block or suppress these reactions to a varying
extent.
A skin prick test is performed by pushing a testing needle through a
drop of testing extract on the skin. The point of the needle carries
a very tiny trace of the allergen into the skin where it comes into
contact with mast cells which are already primed with specific IgE
for all the allergens to which the patient has become sensitised. If
the testing extract contains an allergen which reacts with specific
IgE on the surface of the mast cell, that cell will disintegrate
releasing ‘mediators’ which cause itching and secretion of fluid,
producing a wheal and itching within fifteen minutes if the skin
test is positive. The specific allergen can be compared to a key,
which only turns on the patient’s reaction if it fits the specific
IgE antibody on the mast cells which then liberate the mediators.
Typical examples are hay fever due to pollen, asthma due to dust
mites, and anaphylaxis due to peanuts.
Food Intolerance
Problems investigated by allergists usually include anaphylaxis,
acute food allergies, asthma, hay fever, perennial rhinitis,
allergic conjunctivitis, urticaria and sometimes eczema. Some
allergy specialists have a major interest in the immunological
aspects of allergy, and are less likely be interested in food
intolerance where diagnostic tests have not yet been developed so
that the only way to establish a diagnosis is by manipulating the
diet. Sometimes, after reading an article in a magazine, patients
with chronic problems may ask their doctors if the cause of their
troubles could be in their food. Unfortunately this suggestion is
often rejected because the British medical profession are usually
unaware that a very wide range of disease can sometimes be caused by
allergy or intolerance to foods.
We will never know how often food is a causative factor in many
illnesses until large trials of elimination diets in a wide variety
of chronic conditions are carried out. This is unlikely to happen
because of the current tendency to suppress symptoms with
medication, and the fact that what most people want is a pill for
every ill, and a quick fix. The introduction of an elimination diet
for two or three weeks could exclude the possibility of food
intolerance being part of the problem. There is nothing to lose but
a few pounds!
Intolerance to foods presents much less clear cut problems than food
allergy. The main reason is that the association between eating a normal amount of the food and its adverse effects is usually
delayed by some hours, often the next day, or may even build up over
several days. These slow reactions make it difficult to obtain
clear-cut cause and effect evidence to prove if a specific food is
causing the problem or not.
Skin and RAST blood tests are negative in Intolerance because IgE
antibodies are not involved in intolerance reactions to foods, and
how and why reactions takes place has yet to be discovered. At the
present time the only method which can be relied on to identify the
food or foods causing a problem is dietary manipulation. This is a
procedure which requires dedication and strict compliance by the
patient, but when carried out properly the identification of the
causative food can revolutionise the lives of some patients.
Uncontrolled or desultory dietary manipulation and experimentation
can result in diets which are actually harmful, so it is very
important to establish beyond doubt that the patient is truly
intolerant of a specific food. To be certain it is essential to
demonstrate that the consumption of the same normal amount of the
suspected food will produce the same effects after about the same
time interval on two, but preferably three occasions. This can be
difficult.
Many tests promise quick answers, such as Kiniesiology, Vega
testing, bio-energetics, and many other tests available in health
food shops or from unqualified practitioners. Very expensive blood
tests are advertised direct to the public which claim to find IgG
type antibodies against specific foods in a drop of your blood, but
these tests which have never been subjected to acceptable clinical
trials.
For example a recent patient who had been avoiding wheat and milk
for two years because she suspected them as the cause of her
migraine and Irritable Bowel Syndrome had sent a drop of blood for
testing, and was surprised that antibodies to wheat and milk were
not found by the laboratory. When she questioned this result she was
informed that the reason IgG antibodies to wheat and milk were
absent was that she was avoiding these foods! As specific IgG
antibodies are produced in normal people, this suggests that the
significance of IgG antibodies is very doubtful indeed.
Foods which are eaten daily or several times a week may not be
suspected as a possible hidden cause of a chronic problem such as
asthma or eczema which is being controlled more or less effectively
with drugs, hence without trying an elimination diet for a trial
period these hidden factors will never be found. Foods should be
considered as a possible hidden cause of so–called ‘brittle’ asthma,
a term applied to many middle aged patients with severe asthma. This
term is simply a label which means unstable and difficult to
control, and these patients are often completely dependent on oral
steroids.
To make things even more complicated, the sensitised organ of the
body sometimes changes over the years. For example a daily food,
particularly milk, can cease to cause gut problems, and instead
cause chronic eczema or asthma, as shown in the Holistic Diagram in
the Introduction. Over a period of twenty years or more I have seen
a few patients who began with irritable bowel or mild colitis, get
better with a milk free regime, then get careless about diet and
develop arthritis, followed years later by asthma due to a different
food this time. These remarkable patients often observe the
connection themselves, but unfortunately have their ideas rubbished
by family doctors and even by consultants in the various special
departments they get referred to. Case-histories elsewhere
illustrate these unusual cases. Food Intolerance is a very
ill-defined condition, and there are no reliable blood or any other
tests which will tell you what not to eat to get better.
Allergies can be Multiple, and Intolerance can co-exist with Allergy
Sometimes several body systems are involved. For example many
asthmatics also have nasal allergies which are often overlooked, and
sometimes eczema as well. Sometimes the part of the body affected
will change over the years, and patients may attend several special
clinics instead of only one general allergy clinic. Unfortunately
special departments may be unaware of the possibility that allergy
could be the cause of a problem they are treating.
Over-specialisation can create unnecessary boundaries between
specialities and ignore the fact that the various organs and organ
systems function as a team, so that the human body functions as a
whole, not as separate systems. As illustrated by the global
diagram, allergy can affect any part or several parts of the body,
so that the doctor or his patient may have difficulty in deciding if
the problem is due to an allergic reaction or not. Allergies can
mimic many other medical problems, especially when related to
digestion.
Other Abdominal Complaints
Everyone knows that vomiting and diarrhoea can be caused by an
infection, such as salmonella, or because the food contained some
toxic or poisonous substance which is being rejected by vomiting or
diarrhoea. Sometimes people develop a psychological aversion to a
food which will make them sick if they eat it For example, when an
orthodox Jewish lady was told that the meat she had just eaten and
enjoyed was pork she promptly vomited.
Chronic bowel disorders have many causes as well as allergy or
intolerance, so it is premature and unwise to jump to conclusions
that a complaint is caused by an allergy, or that specific foods are
causing it. For example there may be insufficient enzymes essential
for digestion of milk, such as lactase, the absence of which causes
diarrhoea. Gluten from wheat may damage the lining of the gut
causing coeliac disease, additives such as sulphites, flavouring
agents, MSG,, preservatives, and dyes sometimes cause problems, but
less often than usually thought to be the case..
An attack of diarrhoea on holiday may damage the lining of the gut
so that, after recovery from the acute phase, chronic problems
persist. Several cases have been seen whose “irritable bowel”
cleared up after avoiding milk and milk products. Reintroduction of
milk a few months later caused no relapse, suggesting that the
infection had damaged the lining of the gut producing a temporary
intolerance of milk, and a deficiency of enzymes, which had recovered
with temporary avoidance of milk.
Abdominal symptoms can have many causes, so it is essential to
consult the doctor who will, if it is considered necessary, arrange
for an investigation by a gastroenterologist to exclude serious
possibilities before jumping to the conclusion that the problem is
related to food.
Coeliac disease is caused by a different sort of reaction where
gluten, mostly derived from wheat, destroys the lining of the
intestine and prevents the normal absorption of nutrients,
especially fats, resulting in pale stools, diarrhoea, malnutrition, and many
other problems. This disease is very important to discover because
with total avoidance of gluten the wall of the gut heals and
regenerates, and a complete cure is to be expected, but gluten has
to be avoided permanently. Coeliac disease is not usually classified
as an allergic disease, as the antibodies are not the IgE type, and
it usually falls within the specialty of gastro-enterology, but
diagnostic blood tests are available to any GP if it is suspected.
In recent years tests for Coeliac disease have been improved and
made more sensitive, and as a result milder forms of this disease
have been found to be much commoner than was previously thought.
Non-allergic Respiratory problems
Farmers lung, bird fanciers lung, and similar problems are caused
by the inhalation of organic dusts at work or in the home
environment from keeping birds, and are usually dealt with by
Respiratory Disease physicians These serious problems are to be
found in farmers, bird breeders, pigeon fanciers, and anyone
inhaling any kind of organic dust. The cause is a reaction of the
immune system to these inhaled dusts, with the development of a
precipitating antibody response to these dusts which is not IgE
mediated, and will cause irreversible damage to the lungs unless
diagnosed early. These problems are not related to asbestosis or
silicosis caused by inhaling inorganic asbestos or silica dusts,
usually at work.
Blood tests for bird fanciers and farmers lung are available to any
GP in the NHS, and have been greatly improved in recent years, but
the diagnosis will never be made until irreversible damage to the
lungs has occurred unless the doctor is aware that even one budgie
is enough to cause this disease. An asthma nurse specialist in
charge of a Chest Clinic was always warning her husband, who was a
keen pigeon fancier with a loft full of pigeons, to be very careful
about the danger posed by dust from the loft and bloom on the
pigeon's feathers.
Unfortunately, she did not realise that her
insidiously increasing breathlessness was due to bird fanciers lung
caused by a single budgerigar she had had for five years, in her
kitchen, until she
was quite seriously ill, and the diagnosis was made.
Early diagnosis and removal of the bird will prevent these
unfortunate patients from becoming steroid dependent chronic
invalids. I will never forget being asked to see a patient at home
and found her lying on a couch right underneath the budgie’s cage! I
would have been stupid not to realise the diagnostic significance of
this scenario.
Coeliac disease, and lung diseases caused by inhaling organic dusts
now have the great advantage that there are blood tests available
which can lead to a definite diagnosis, but the possibility has to
be suspected before these tests will be done.
Today it is much less
likely that a family doctor will be aware that a patient with chest
problems is a pigeon fancier or keeps birds, because home visits are
seldom carried out, there is little time for taking a full history,
and patients do not always see the same doctor so that continuity of
care may not be possible. |