Letter from Professor Chris Corrigan,
Professor of Asthma, Allergy & Respiratory Science and Consultant
Physician, Guys Hospital
I am pleased to submit written evidence for
this Committee in my capacity as Consultant Allergist and Researcher
at Guy's Hospital, London, which is one of the biggest NHS centres
for treatment of allergic disease in the UK, as Educational Supervisor
to two allergy SpR trainees, as Secretary of the Joint Committee
on Higher Medical Training Specialist Advisory Committee on Allergy
and as counsel member of the British Society for Allergy and Clinical
Immunology, the professional body for clinical and non-clinical
doctors and allied health and other scientific professionals working
in the field of allergy.
DEFINING THE
PROBLEM
Allergic diseases represent a particular class
of immunological "hypersensitivity" reactions ("hypersensitivity"
reactions are immunological responses produced in certain persons
which, instead of being advantageous to the person, such as in
fighting off infections, are actually harmful by causing tissue
damage, disruption of vital organ function and even death). Allergic
hypersensitivity reactions occur because certain individuals have
a propensity to produce an allergic antibody called IgE, which
recognises external foreign proteins which find their way to the
mucosal surfaces of the skin, airways or bowels of predisposed
patients. The particular proteins which set off these responses
are collectively called "allergens". It is not known
why some individuals make IgE antibodies to allergens whereas
others do not, even though everyone is exposed to a broadly similar
range of allergens by breathing them in or swallowing them. Once
the allergic IgE antibodies are formed, they coat the surfaces
of special inflammatory cells in the tissues or circulating in
the blood called mast cells and basophils respectively. Further
exposure to allergen then causes these cells to degranulate or
burst, releasing a number of toxic inflammatory substances including
histamine, leukotrienes and prostaglandins. Allergic reactions
are characterised by their immediacy: that is, exposure to allergen
causes mast cells and basophils to release their toxic inflammatory
substances within seconds of exposure. This is why allergic reactions
belong to the class of hypersensitivity reactions called "immediate
hypersensitivity". Histamine, prostaglandins and leukotrienes
induce generalised effects on the body, particularly lowering
of the blood pressure which can lead to fainting, collapse and
cardiac arrest, constriction of the bronchi or breathing tubes,
causing shortness of breath and wheeze which may be particularly
severe in asthmatics, and the swelling of the tissues, which may
cause a rash on the skin but also swelling of critical organs
such as the larynx which may block the airway and is another potential
cause of death in severe allergic reactions.
As allergists we recognise quite clearly which
diseases are caused by, or made worse by allergic "hypersensitivity"
reactions. These include asthma, allergic rhinitis (including
hay fever), eczema, anaphylactic reactions to bee and wasp stings,
reactions to latex proteins and some, but not all reactions to
foodstuffs and drugs. In contrast the general public and many
medical and allied health professionals, because they have had
little training in allergy, tend to classify a much wider range
of reactions to external agents as "allergic" inappropriately.
This is typified by the situation with food allergy and intolerance.
Food allergic reactions are immediate, reproducible and evolve
with a very typical pattern in allergic individuals. It is possible
to tell whether or not patients have true food allergy with a
brief history and relevant simple tests. On the other hand, many
patients (and often their doctors) attribute a range of non-specific
symptoms to foods which occur much later after they have been
eaten and very widely in their clinical manifestations. There
is little or no evidence that such late reactions are caused by
reactions to foods, and the term "allergy" is in this
case not appropriate. If late reactions to foods do occur (and
there is no definite evidence that they do except in rare patients
with very well defined inborn areas of metabolism which cause
biochemical abnormalities after eating certain foods, and with
the exception of coeliac disease, a rare non-allergic hypersensitivity
reaction to gluten found in various grains), their mechanisms
are uncharacterised and consequently there are no suitable diagnostic
tests.
Allergic disease is characterised by the so-called
"allergic march" in which infants predisposed to allergy
typically developed severe eczema soon after birth. This is followed
by manifestations of food allergies, typically to cow's milk,
egg, grains, nuts and fish which develop about the time these
foods are introduced into the infant's diet, and later allergic
rhinitis and asthma. In such patients, allergic reactions to foods
and airborne allergens such as pollens and animal danders can
be demonstrated by simple tests such as skin prick tests. One
of the major mysteries in allergy, however, is the fact that many
of these diseases tend to remit clinically as the child gets older,
yet this is not usually accompanied by produced production of
allergic IgE antibodies. Having an allergic reaction is not, therefore,
simply a question of whether or not the body makes IgE antibodies.
Clearly, there are whole layers of understanding to be uncovered
about what governs the presence and severity of clinical allergic
reactions in patients and how this varies with time. It seems
very likely that environmental factors, as well as possible genetic
predisposition of certain individuals govern these processes,
but little or nothing is known about their nature.
Although there is unequivocal evidence that
the prevalence of allergic diseases is rising with epidemic proportions,
it is also very clear that the burden of disease is grossly underestimated
for all types of allergy. There are several factors operating
here. First, because allergy has only recently existed as a separate
medical speciality in the UK, specific allergy training never
has been, and still is not included in undergraduate and postgraduate
medical training curricula, much of it goes unnoticed. For example,
many patients with chronic allergic rhinitis are characterised
as having a "permanent bad cold" and suffer needlessly
for years on end when they could be helped by appropriate allergy
diagnosis, identification of causal allergens, appropriate allergen
avoidance advice and ancillary medical treatment. Many cases of
acute "asthma" presenting to casualty departments are
in fact acute anaphylactic reactions (a severe, generalised allergic
reaction which may be fatal) caused by oedema of the larynx referred
to above, and not asthma at all. Even experienced accident and
emergency and general internal medical consultants have had little
training in the recognition and subsequent management of allergic
diseases. Food allergy reactions in infants often go unnoticed,
since the symptoms of anaphylaxis are less dramatic (but still
potentially lethal) in infants as compared with adults. Yet food
allergy can cause untold suffering in children, with exacerbation
of coexisting eczema, asthma and rhinitis. A further gap in recognising
the burden of disease is that, because there is not NHS infrastructure
for the management of allergic problems, many patients elect to
treat themselves, often very unsatisfactorily, and never present
to a medical practitioner. In many areas of the UK, there exist
no allergy specialists to see these patients even if they do decide
to seek help. A clear solution to all of these problems is to
establish a network for allergy treatment across the UK, a course
of action which was recommended recently by the House of Commons
Health Committee but sadly ignored by the Department of Health.
The socio-economic impact of allergic disease
is tremendous and largely unrecognised. Untreated allergic rhinitis,
for example, is in the top five causes of lack of sleep in the
general population. It is also in the top five causes of loss
of time from paid employment. Asthma rates slightly higher in
the league table of causes of loss of days at work or school,
with enormous socio-economic implications. For example, over 12.7
million working days are lost to asthma each year. Asthma costs
the NHS an average of £889 million annually. One child in
every year of every school in the UK now has peanut allergy, and
in some children this is potentially fatal. Away from impressive
statistics, bad hay fever in the summer ruins the social lives,
morale and examination performance of millions of young adults
every summer.
TREATMENT AND
MANAGEMENT
Until recently no known treatment was proven
to alter the natural history of allergic disease. There are recent
exciting suggestions that certain forms of immunotherapy, particularly
with modified allergens, may do so. While pharmacological and
non-pharmacological therapies (not least sensible and authoritative
allergen avoidance advice) have had a major impact on the burden
of allergic symptoms, the key to cracking allergy is prevention.
At present the level of research aimed at understanding
the natural history of allergy, the role and scope of primary
prevention and altering the natural history of the disease for
the better is grossly inadequate. We have been lucky enough to
set up, in collaboration with King's and Imperial Colleges, Asthma
UK (the country's leading asthma charity) and the Medical Research
Council the first MRC Centre for allergic mechanisms of asthma.
Apart from this, allergy research is performed in isolated centres
of excellence by a small handful of interested individuals. The
lack of an organised and structured NHS allergy service has greatly
hampered this process, resulting in few young doctor trainees
who are interested in doing it, and lack of nationwide access
to patients to participate in research projects.
The most promising areas of research into preventing
or treating allergy at present might be summarised as follows:
(1) Strategies for prevention: attention
to maternal and foetal nutrition, and other early interventions,
such as allergen vaccination, which may alter the evolution of
allergic disease.
(2) Measuring and assessing life-time allergen
load and exposure.
(3) Drug allergy: organised clinical and
epidemiological research, with assessment of outcomes of management
by allergists.
(4) Further development of allergen immunotherapy
(the practise of exposing allergic individuals to progressively
large quantities of the allergen at a distinct mucosal surface,
such as by injection or under the tongue) is of proven therapeutic
benefit. For example, patients with anaphylactic reactions caused
by allergy to bee or wasp stings can now be cured of this problem
with immunotherapy. With hayfever, immunotherapy can vastly reduce
symptoms and transforms sufferers' lives. There is also evidence
that immunotherapy reduces the need for conventional medical therapy
in asthma. Most interesting of all, however is the evidence that
early immunotherapy may reduce the incidence of new allergic sensitisations
and the emergence of clinical allergic disease in infants and
children. Advances in the formulation and practice of immunotherapy
are being made all the time. For example, sublingual immunotherapy
for grass pollen allergy has recently become available in the
UK. New modifications to allergens to increase their ability to
turn off the allergic immunological hypersensitivity response,
through better understanding of the immune system and how responses
to allergens are regulated, are emerging all the time. There is
abundant scope for a nationwide initiative to investigate the
efficacy and long-term effects of these interventions. This is
likely to save the health service millions of pounds in the medium
to long term, not to mention the socio-economic impact of reduced
loss of time at work and school.
(5) Investigation of what factors determine
an individual's susceptibility to allergic disease. As mentioned
above, this is not simply a question of whether or not they make
allergic IgE antibodies to a particular allergen. Virtually nothing
is known about this field, yet it promises such scope for understanding
the role of heritable and environmental factors in turning clinical
allergic reactions on and off.
(6) The impact of early intervention in food
allergy, in terms of manipulation of maternal diet and the introduction
of possible ancillary substances which will head off the development
of an allergic response. Despite increasing interest in the role
of a foetal and maternal environment in governing the evolution
of allergic disease in susceptible patients, few concrete recommendations
have so far been possible, and this reflects lack of appropriate
and directed research.
GOVERNMENT POLICIES
To my knowledge, apart from the publication
of pollen counts which are generally measured by private organisations,
no government policy has directly addressed the epidemic of allergic
disease or produced sufficient public information to aid sufferers
with self treatment or by providing the impetus to seek specialist
allergist advice. Housing policy and regulations pay little or
no attention to allergy, even though the environment likely plays
a major role in the epidemic rise in allergic disease. Factors
such as nitrogen dioxide emissions from gas burners, the emission
of volatile organic compounds from mass produced furniture and
the growth of moulds and other allergens in damp or ill ventilated
homes may all play a very important role in the epidemic of allergy.
Simple design of homes to minimise the accumulation of allergens
such as dust mites, or more research into effective means of ventilation
and control of humidity might revolutionise suffering from allergic
disease. Food policy and labelling regulations have gone some
way to help food allergy sufferers, but on the other hand, largely
to protect themselves from legislation, many companies have overstated
the likelihood of their products containing particular allergens
(a typical example is the label that a food "may contain
nuts"). Such practices are not helpful to the sufferer who
may die from anaphylaxis from accidental nut exposure, and the
situation may require expert dietetic input which is really only
available at dedicated allergy centres.
PATIENT AND
CONSUMER ISSUES
Even notwithstanding the impact of allergies
on the quality of life of sufferers and their families, the figures,
only a few of which I have quoted above, really speak for themselves.
It is absolutely inconceivable to allergists how these issues
are ignored when allergic disease is one of the leading causes
of morbidity, suffering, NHS expenditure and socio-economic loss
in the UK. It is widely perceived that this outrageous anomaly
arises simply because allergic diseases are not political "hot
potatoes" like cancer and heart disease. Certainly, government
spending, health priorities and public education are certainly
not the slightest bit attuned to the prevalence and impact of
allergic disease.
Finally, may I say a final word about "over
the counter" allergy tests. Many so called "allergy"
tests performed, for example, in health food stores or alternative
medicine emporia are of no diagnostic value whatsoever. Furthermore,
they are misleading in the sense that the patients are often given
a completely erroneous and ad hoc list of foods or other
substances they should apparently avoid, which not only does not
treat the allergic disease but also leads to inappropriate dietary
restriction, sometimes to the point of starvation, particularly
in children with anxious parents. Even "over the counter"
tests of accredited diagnostic worth, such as RAST (a blood test
for allergic IgE antibodies), are effectively useless unless interpreted
in the light of the patient's history, which can only be done
by an experienced allergist. It is a constant source of dismay
to allergists that practitioners offering so called "allergy
tests" of no diagnostic value are allowed to set up shop
and dupe the public in such an outrageous manner, seemingly with
no legislative control at all. The fact that these services are
used so widely is on the other hand no doubt a reflection of the
desperation of allergy sufferers in obtaining access to any form
of help at all.
In conclusion, allergy could effectively be
managed in the long term if the Department of Health was to allocate
adequate resources and "kick start" the service across
the country. This would lead not only to a structured system of
management of patients with allergic diseases across the UK, but
would also form an invaluable platform for research.
At present, after rising from the ashes about
six years ago, the speciality of allergy is once again struggling
at the brink of death in the UK. Despite recognition of the speciality
and a clear, full and exciting training programme, there are currently
just eight young trainees in allergy across the entire UK. They
are increasingly disillusioned about their future careers and
see no growth of specialist centres where they can practise their
art. The situation is something of a vicious circle since there
are correspondingly few centres at which allergists can be fully
trained. A career in allergy is exciting and offers a real opportunity
significantly to improve the lives of a vast range of people,
young and old. It is imperative that the Department of Health
facilitates a career pathway for these young people by undertaking
the clear recommendations of The Royal College of Physicians and
of the House of Commons Select Committee. I therefore implore
the honourable members of the Committee to consider this dilemma
gravely and beg them to take the appropriate action.
6 October 2006
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