Examination of Witnesses (Questions 600-619)
28 FEBRUARY 2007
MRS MARGARET
COX, PROFESSOR
DAVID GAWKRODGER,
DR CLIVE
GRATTAN AND
DR SHUAIB
NASSER
Q600 Chairman: If I may follow on
from that, how adequate are the services to enable allergic triggers
to be diagnosed amongst patients? Is there a cohort of patients
there who currently are not accessing the appropriate diagnostic
services to detect an allergic trigger to their skin diseases?
Dr Nasser: The answer is "yes".
There are very few specialist allergy centres in this country
as you will be aware from previous hearings. There are something
like six full-time specialist centres dealing with allergic disorders
and perhaps only 30 full-time equivalent allergists compared to
a couple of thousand in, say, Germany. In terms of being able
to access an allergic diagnosis for your eczema, you are actually
very unlikely to be able to achieve that and eczema is a very
common disorder as are all the other allergic diseases. Food allergy
is increasingly common as is hay fever and asthma. It is not just
the milder forms, but in fact the more severe forms of these disorders
that are seen increasingly. So, it depends where you live whether
you can access these services. There are some dermatologists who
are interested in both aspects and Clive Grattan is an example.
So, there is a considerable overlap but there are many dermatologists
who are not able to access allergy services at all.
Q601 Chairman: Mrs Cox, would you
like to answer that from the patient perspective.
Mrs Cox: I would agree wholeheartedly
that, from the patient perspective, where you live makes a huge
difference and that many patients are not able to access an allergy
related service for their eczema. I would also add that, in consequence,
what is tending to happen, particularly with parents of children
with eczema, is that they are guessing around allergy, they are
frequently guessing that it is diet and they are tending to embark
upon do-it-yourself diet avoidance which in many cases is probably
not going to impact upon the eczema but might well impact on the
overall well being of the child and meanwhile the eczema itself
remains untreated.
Q602 Lord Haskel: May we move on
to the environment and ask you what environmental factors contribute
to the development and exacerbation of diseases like atopic dermatitis,
eczema and urticaria and whether there are any environmental measures
that we can take to prevent these disorders developing.
Professor Gawkrodger: That is really
quite a complex question. When it comes to the environment, there
are a number of interactions between the skin and the environment
because the skin is really the first barrier of the body and the
immune system, so the skin is actually there to protect you from
the environment but it is there to be damaged by the environment
as well. If you have any sort of skin disease, then there are
certain environmental factors that may make it worse. The exact
factors that might worsen almost any sort of skin disease might
be different. If you think about atopic eczema and you just consider
what external environmental factors might be playing a part, then
you have things that are non-specific irritants such as wet work,
wind, cold, heat, dryness and other environmental things like
that, and you have frictional things which may be rubbing of the
skin or rubbing of frictional materials against the skin, and
you also have chemical allergy as well, chemicals that come into
contact with the skin either applied by the person themselves
or which they have contact with at work may actually induce either
an allergy or produce an irritant which has a type of toxic effect
that is not allergen mediated. Whether you develop a contact dermatitis
or not depends on a whole number of different factors. It can
depend on the actual chemical structure that comes into contact
with your skin. For example, they tend to be small sized molecules
which tend to be more allergenic than large ones but not always,
it depends of the concentration, the solubility of the chemical
in water or liquid and it depends on your personal predisposition
to become sensitised which varies between different people. I
think probably I will stop there having said a fair bit and let
somebody else have a go.
Dr Nasser: We have heard about the non-specific
triggers and, certainly if you have eczema, then non-specific
triggers will aggravate the eczema and a classic example is swimming
in chlorinated water which will often aggravate patients' eczema.
There are some specific triggers and specific allergenic triggers
for example latex, and wearing latex gloves can aggravate patients'
pre-existing eczema. I saw a first-year veterinary student yesterday
who had to leave her lesson because contact with a horse within
minutes aggravated her eczema, so much so that she was unable
to stay, and it had happened to her on a number of other occasions.
There are many factors that can aggravate eczema. In a proportion
of patients inhaled allergens, for example animals and house dustmite,
are important allergens. Also, in the environment, I suppose you
could add infection. Certainly infection will aggravate eczema
and that is something that is often not appreciated especially
in primary care.
Dr Grattan: I think it would be worth
at this stage making clear that atopic dermatitis and allergic
contact dermatitis are completely separate conditions and the
replies you have had to some extent merged those two illnesses
together. Atopic dermatitis may have a genetic component that
allows people to develop it in addition to asthma and hay fever
and there may be environmental triggers and factors as we have
heard. Allergic contact dermatitis on the other hand can happen
to anybody. I do not believe that there is an underlying genetic
predisposition. Also, it depends on the concentration and prolongation
of exposure to the chemical allergen whether or not sensitisation
and an allergic skin disease develops. I think it is important
to separate those two and discuss them separately.
Professor Gawkrodger: I do not entirely
agree with you there in that an awful lot of people who will be
developing an allergic contact dermatitis actually have an atopic
background. I think that you have to look at the patient in the
round and, when I conduct my contact dermatitis clinic, I want
to know the atopic status of the people I am seeing. In addition,
I think that there is a genetic predisposition towards being sensitised
to chemicals in terms of allergic contact dermatitis. I think
that some people become sensitised and some people do not. There
are genetic factors which I would say we do not fully understand
that are playing a part.
Q603 Lord Haskel: What measures can
we take to prevent these disorders developing? We can just simply
avoid food allergens or possibly house dustmites, but there are
a number of things which we cannot avoid in the environment such
as fragrances, cleaning fluids and this sort of thing. Is there
anything we can do to prevent this such as the pre-testing of
products and that sort of thing?
Professor Gawkrodger: There is European
legislation on this matter and I would refer you to the European
legislation on chromate in cement which is particularly important
for hand dermatitis in construction workers. The chromate sensitises
people and they develop a chronic hand dermatitis, and there is
some evidence that reducing the amount of available chromate in
cement by adding ferrous sulphate has actually reduced the incidence
of that. There is European legislation on the amount of nickel
in jewellery and there is some evidence that that has reduced
the evidence of nickel allergy which may be associated with certain
types of dermatitis. In addition, European legislation on the
labelling of fragrances or labelling of the ingredients in cosmetics
has come into play and that has been very useful because we can
advise patients whom we diagnose as being allergic to certain
things to avoid these things. I would share your concern about
our wider exposure to things like fragrances and it is particularly
worrying in children's products where children are being exposed
now to a lot of fragrances and we do not know what is going to
happen in, say, 10 years time. Another area of concern is hair
dye. That is a chemical called paraphenylene diamine which is
virtually the only chemical which will actually dye hair. It is
present in up to six per cent concentration in hair dye and, with
the increased frequency of hair dyeing—up to 70 per cent
of women and up to 20 per cent of men actually dye their hair—and
with younger and younger age groups of people dyeing their hair
for fashionable reasons, allergy to hair dye is quite a concern
and I think probably warrants further inspection as to whether
there are alternatives and whether it is actually safe. On a European-wide
basis, certain preservatives which may produce a contact allergy
have been banned because they have caused too many problems. I
think that legislation can be helpful in limiting contact with
problem chemicals.
Q604 Lord Taverne: With the very
widespread fashion for hair dyeing, has there been an equivalent
increase in the number of allergens?
Professor Gawkrodger: It appears that
there have been. I cannot quote you the publication off the top
of my head. The problem with paraphenylene diamine is that you
can get very severe reactions. You can get severe swelling of
your face and neck requiring you to have treatment with systemic
prednisolone to get it down. I believe that there has been an
increase. I cannot quote you the exact paper but one of the problems
is the severity of the reaction.
Q605 Lord Haskel: What about non-clinical
things like air conditioning which we are all subjected to? You
mentioned that infections were a cause. Can we do anything about
the quality of the air or something like that?
Professor Gawkrodger: When it comes to
the area of air conditioning, it is difficult to say whether it
causes problems with their skin. I do ask people about that and
I think that sometimes, if you have a tendency to get dry skin,
excessive air conditioning may actually make your skin worse,
but it has not actually, as far as I am aware, been very well
researched.
Dr Grattan: May I expand a little on
the hair dye sensitivity prevalence. There is some information
on that and it is contained within a document which I believe
has been submitted to this Committee and is therefore before you.
I can read it if you wish.
Q606 Chairman: Are you referring
to the BMJ editorial with all the references in it?
Dr Grattan: Yes and there is a further
document which has been produced by my colleagues I believe at
St John's Institute of Dermatology which contains that information.
Q607 Chairman: Yes, thank you.
Dr Grattan: There is one other area of
avoidance which has been a success story and that is powdered
latex gloves for healthcare workers. It was recognised some years
ago that having powder within latex gloves appeared to be linked
with the increasing incidence of latex allergy and, since powder
has been banned, at least in Germany and I think thoroughly discouraged
in the UK, the incidence of latex allergy is falling. The investigation
into latex allergy does also illustrate the overlap between allergic
contact dermatitis and urticaria which Professor Gawkrodger was
talking about and I separated them out for simplicity only but,
as an example, someone who reacts to a rubber glove may react
to the natural latex protein with an allergic mechanism which
is Type I and relates to eczema, asthma and hay fever, or to the
chemicals used to cure the rubber and then that would be the Type
IV mechanism which would be diagnosed by patch testing, so there
is an overlap of dynamics for the treatment of patients and their
condition.
Q608 Chairman: Mrs Cox, would you
like to come in at this point?
Mrs Cox: Looking at this in an overarching
way, I suggest that there is a tendency for us to hugely underestimate
the importance of our skin as our barrier to the outside world
and a need for people to have a better understanding of the need
to protect their skin and, to the extent possible, not to go into
total avoidance of everything but to be sensible about what they
put on their skin and perhaps, more importantly, their children's
skin and not to be tempted into thinking that everything which
is promoted as being "good for your skin" and "good
for your baby" is actually good for either.
Q609 Lord Colwyn: Some of us went
to Germany to take some evidence—unfortunately I had to
miss the trip—and there we saw the dermatologists do what
is described as an allergy work-up for atopic dermatitis and urticaria.
Can you tell us whether all dermatologists do this in the UK and,
if they do not, why do they not?
Professor Gawkrodger: I am not sure what
the work-up was. Are you able to say what it was?
Q610 Chairman: We heard from the
allergy clinic there that they go through an exclusion process
actively looking for allergens.
Professor Gawkrodger: I think that is
probably not common practice in the UK. Certainly in my department
and with my colleagues, I think when it comes to somebody with,
say, atopic dermatitis, we will take a history and I think that
the history is the key thing. We will ask whether there are any
triggering factors and I ask people if they think that there are
any foods involved. It depends a little on the severity of the
eczema. If it is somebody with mild eczema that can be easily
controlled, I think that we will not probe too deeply. If it is
somebody with more severe eczema, we will certainly look for whether
there may be a contact dermatitis complicating the picture, in
which case patch testing would be part of the work-up and, in
my department, we do actually patch test people with atopic eczema
to aeroallergens. I certainly would take blood investigations
for immunoglobulin E and I might actually look for some food allergies
if the patient had given a very strong history of food allergy.
I think I might be going beyond what the average dermatologist
would do there because I have a particular interest in allergy
and the skin. As to why British dermatologists do not do such
a major work-up—and I would agree that they do not in most
cases—I think that perhaps part of the answer is pressure
of work with there being only 500 dermatologists and another aspect
is also availability to undertake allergic investigations particularly
for prick-testing which is quite a time consuming investigation—that
is where you prick in the allergens into the arm—but maybe
also that there is a trend for British dermatologists not to regard
an allergic input into the dermatitis in the same way as people
do in perhaps Germany in most cases.
Q611 Lord Colwyn: How is it in Norwich?
Dr Grattan: I also have an interest in
skin allergy and I think that one of the limiting factors that
I experience and many of my colleagues experience is offering
patients sufficient time. Certainly, a full consultation may take
at least 30 minutes and for more sophisticated allergy problems
45 minutes. The structure of clinics often precludes allowing
that amount of time, and from history flows the investigations
and I would direct at problems that I identify from the history
as opposed to giving a battery of tests to everyone.
Mrs Cox: Could I add that what we are
hearing here is experience in relation to secondary care and in
fact hugely the majority of patients with atopic eczema will be
seen in primary care and, in that environment, very few, if any,
will have any allergy issues investigated at all and fairly obviously
time is a huge factor.
Chairman: We have spent quite a lot of
time on this first bit of questioning and we now need to speed
up. I will now move to Lord Taverne and ask you to keep your answers
concise and we will be able to move through all the other questions
that we have.
Q612 Lord Taverne: How many people
in the United Kingdom currently suffer from atopic dermatitis,
atopic eczema and urticaria and how has the incidence of these
diseases changed over recent years?
Professor Gawkrodger: With regard to
atopic dermatitis, at the present time, about 20 per cent of the
children have atopic eczema and that is an increase compared to
about 50 years ago we suspect, although really good studies previously
were not actually done. Of those children, I would say that approximately
50 per cent will grow out of it in their teens which leaves you
with 10 per cent of adults who will have atopic eczema to a greater
or lesser extent, and it may be very mild in terms of just some
dryness of the skin or it may be very severe, it varies. I will
let someone else answer about urticaria.
Dr Nasser: Dealing with atopic eczema,
there are some studies that show a threefold increase in the last
20 years or so and there is a Welsh study which in 1973 showed
a five per cent incidence of atopic eczema amongst 12-year olds
and by 1988 that had gone up to 16 per cent. There are other international
studies and there is a very good study, the ISAAC, the International
Study of Allergy and Asthma in Childhood, which looked at both
cohorts, and they found a 22 per cent prevalence of atopic eczema.
So, we know that these diseases have increased enormously in the
last 15 to 20 years and I would certainly go along with the fact
that many of these patients do not have resolution or they do
not grow out of their symptoms into adulthood although the severity
of the condition may have improved.
Dr Grattan: The prevalence of urticaria
is effectively unknown because there are no good studies that
looked at this. Estimates range from as high as 30 per cent of
the population of a country being affected by one form of urticaria
or another over their lifetime to as low as one per cent, and
good data are needed. I cannot tell you if the incidence has gone
up. It may have but I do not know.
Q613 Lord Taverne: Who records the
number of people suffering from these diseases?
Professor Gawkrodger: Nobody records
them officially. Any sort of study is a research investigation.
Q614 Lord Taverne: The Department
of Health said that there are currently problems regarding the
data collection of allergic diseases and they hoped that the introduction
of a new nomenclature system, which they elegantly describe with
an acronym called SNOMED, would enable allergy to be classified
more specifically when clinicians enter data on to patient records.
Do you think SNOMED will enable the prevalence of allergic skin
diseases to be more accurately recorded?
Dr Nasser: Maybe I can talk a little
about that. I have certainly come across SNOMED but it is at an
embryonic stage so it is not yet being used. The principle is
that every allergy patient has a diagnosis recorded, but it is
important that the correct diagnoses are placed into the system
in the first place which can only happen if the doctor is appropriately
trained in allergy.
Q615 Lord Colwyn: May we move on
to some of the treatments now. Can you give any common treatments
such as antihistamines and corticosteroids that are used and say
whether you think these actually cure anybody.
Professor Gawkrodger: With regard to
atopic dermatitis, the treatment will depend on the severity of
the condition and also where you are seen. If you are seen in
general practice with mild eczema, I think that first of all you
would be offered moisturiser emollient which is a cream which
can help to treat the dryness of the skin which is one of the
primary symptoms along with itching and also emollient for the
bath or for showering with. If it were more than just mild eczema
and non-responsive to an emollient, then the plan would be to
move on to a topical steroid of which there are different strengths
from mild to moderately potent to highly potent and it is usual
to start with a mild one such as hydrocortisone and move on to
a stronger one if necessary. Any infection that is present, which
is not an uncommon thing, should be treated as well. If the patient
does not respond at that stage, the usual thing is to refer on
to secondary care and there they may try a stronger topical steroid
for a longer period of time, perhaps considering other things
that might be involved and that is where considering other allergic
problems might come in. There are other topical treatments apart
from topical steroids and these are called calcineurin inhibitors,
and they do not have the same side effects as topical steroids,
things like tacrolimus. If people do not respond at that stage,
probably another thing that happens is that the team will look
at the compliance of the patient, so is the patient applying his/her
cream properly, and it is very important to look at that. This
is a common reason why patients do not get better and it is where
nurse practitioners are useful at improving patient care. If these
topical treatments do not work, then it is on to systemic therapy
which is quite a big step because you are on to quite potent immunosuppressive
drugs which can have quite serious side effects but which can
be very helpful for people with the very most severe types of
eczema.
Mrs Cox: Clearly, I would not disagree
with that but again I would like to remind everyone that in fact
most eczema patients are seen in primary care. Certainly in my
experience referral out of primary care into secondary care can
be very hard to achieve. I do agree that compliance with topical
treatments is not always too good but there are several reasons
for that, one of which may well be, particularly in the primary
care environment, that nobody has really had the time or possibly
the expertise to show the patient or the parent how to apply them
in the first place.
Q616 Lord Colwyn: Are there many
patients who do not respond to these treatments? Are you able
to give a rough percentage? I know that it is difficult because
there are varying degrees of the illness.
Professor Gawkrodger: I could not give
you a figure but I would say that, in all of our clinics as consultant
dermatologists, one of the most regular things we see is people
on systemic treatment for their eczema, so there is a quite a
lot of them, but I cannot say exactly what proportion of people
with eczema as a whole have to have systemic treatment. It is
certainly a minority.
Q617 Lord Colwyn: Can you say something
about allergen immunotherapy.
Professor Gawkrodger: I cannot myself.
Q618 Lord Colwyn: Can it be used
to treat atopic dermatitis or urticaria?
Dr Nasser: That brings us on to curing
the condition and that is really what your question is aimed at.
We have heard about lots of pharmacotherapy and the question that
arises is, are there any allergens first of all that you can avoid
which may improve symptoms and other than irritants, are there
any chemicals that you can avoid as this aspect of the management
is also very, very important? One of the things that patients
eventually come to realise is that, when the eczema is severe,
it is very difficult to improve, but, when it is good, it is easy
to maintain its status. So, it is important that patients understand
that. One of the things that we try to do as allergists is to
identify underlying causes in the proportion of patients who have
an allergic cause, and these may be aeroallergens or food. Certainly
that can lead to a reduction in the pharmacotherapy, some of which
have very severe side effects. You asked a question earlier about
the difference in management in different countries and the simple
answer to that question is that there is no education in English
or British medical schools on allergy, so there is no curriculum
on allergy and that is why our general practitioners have very
little understanding of the subject, and I think this is a very
important point. Immunotherapy is not effective in eczema on the
whole. I know that people have tried immunotherapy for eczema
but, as far as I am aware, the results have not been terribly
good, unlike for rhinitis or for some studies in asthma.
Q619 Baroness Platt of Writtle: What
you said just now about no curriculum position for training doctors
was very interesting, but is that perhaps one of the most important
things that ought to happen?
Dr Nasser: The most important thing.
I am glad you picked it up. It is probably the most important
thing that should come out of the Committee's findings.
| 
