- This is Lab Medicine Rounds, a curated podcast
for physicians, laboratory professionals and students.
I'm your host, Justin Kreuter,
a transfusion medicine pathologist
and assistant professor of Laboratory Medicine
and Pathology at Mayo Clinic.
Today we're rounding with Dr. Douglas McMahon from the
Allergy and Asthma Center of Minnesota in honor
of May being national, a Asthma and Allergy Awareness month.
Dr. McMahon is a board certified in allergy
and asthma doctor
and is a frequent lecturer at national medical meetings
for food allergies and asthma.
He's also proud to have served as the director
of outpatient allergy at the University of Minnesota
for four years,
and the president of the Minnesota Allergy Society.
He is also the only allergy trained member
of the Twin Cities Children's Asthma Committee,
and he's a member of the Food Allergy
and Anaphylaxis Network, anaphylaxis
and Food Allergy Association of Minnesota,
Minnesota Medical Society,
and the American Academy of Allergy, asthma and Immunology.
So we're definitely joined by an expert to talk
with us now on National Asthma
and Allergy and Awareness Month.
Thanks for joining us, Dr. McMahon.
- Well, thanks for having me. - Well, it,
it's awesome to have you here.
And for our audience, you know,
I think we have a quite a diverse audience
that are listening and chime into this podcast
since it's allergy and asthma awareness month.
Why is it maybe, maybe to take a beat
and say, why is it important for people to, to kind
of recognize asthma and allergy, to bring it front of mind?
- Yeah, so asthma is something that's very important
because unfortunately people die of asthma.
You know, a lot of people kind of think about asthma as, oh,
you know, I have some troubles here or there,
but, you know, people unfortunately die die of asthma.
So it's definitely something to take, take serious
and to make sure you're under good control all the time,
because you never know when the
exacerbation's gonna be severe.
But also, which is more hits home to more people is
that asthma affects everyday quality of life.
So I grew up with severe asthma,
and that's kind of why I went into this field is that,
you know, there just small activities
that people don't even think about.
You know, little kids sleeping over at a friend's house,
going on a camping trip, playing sports.
All these things can be impacted if you do have asthma.
So it's important to be under really good control for that.
And then allergic rhinitis, you know,
a lot allergic rhinitis is something
that affects millions and millions of people.
Probably one of the most common disorders
in the United States.
And you know, a lot of people right now are seeing it,
you know, spring, spring allergens, the tree pollens.
Some of the molds are really affecting people
and it, it just affects your quality of life where they're,
you know, not sleeping well, having trouble, you know,
with sinus infections, having to skip school, skip work,
just uncomfortable.
'cause they're having a runny nose, sneezing,
itchy eyes all the time.
And so it, it's definitely impactful on people.
- Well, I hadn't really considered about,
and I, I appreciate you kind of bringing this front of mind,
highlighting, I mean, both the, you know, profound aspect
that some patients can die from asthma,
but then also impacting kind of the every day
how this can really kind of impact those around me.
You know, I may not have this diagnosed,
but maybe there might be other people around me
that are affected.
Maybe this is a good time for me to ask then, you know,
are there maybe just for awareness, are there simple things
that, that I might be able to do
that makes it a little easier?
Who people from people that may suffer
from asthma allergies around me?
- Yeah. So one of the, the big ones is, you know, smoking,
you know, people that fortunately don't smoke in public
places as much anymore.
So that's a big one. One thing that's interesting
that we are seeing that a lot
of people probably don't think about is, you know,
how pets people are bringing their pets
around a lot more places right now, you know,
and their airlines and you know, the,
the shopping stores and all this.
And, and people, you know, they, they like their pets
or they want emotional support animals,
but they don't really think about the, the patients
that are allergic to these animals.
And some people have asthma that is flared by that.
And so all of a sudden now you're,
you're inducing these responses.
And so that's kind of a, an interesting thing
that probably a lot of people don't even think
about that have them.
- That's a, a great point.
I imagine, you know, it's, it may,
it sounds like it's probably independent of like, you know,
it might be a, an animal that you're, is, is cleaned and,
and you know, healthy,
but still can set off
exacerbations and those around you.
And so I guess that it brings a mind
of maybe just highlighting if you're gonna bring an animal
by to kind of talk
with people first instead of the surprise.
- Yeah, yeah. If, yeah.
Especially if you're gonna be in some close quarters.
Yeah, for sure.
- So transitioning, one of the things I wanted
to ask you about in kind of talking
before this episode is to understand some
of the newer oral immunotherapy options that are coming out.
We thought this would be a great way to kind
of update listeners in our community to something
that seems very relevant to patients for asthma allergy.
What should our audience understand about these neural new
oral immunotherapy options?
- Yeah, so, so there's,
there's two different aspects of this.
One is for environmental allergies, one is
for food allergies.
They both work on the same premise that giving small amounts
of the allergen.
If you start small enough over time, giving more and more
and more, your body can alter the immune response.
So, so basically the, the two response is
what a lot of the people who have an allergic response are
in this two realm.
And the notion is, is can we switch that back to, you know,
either a lower response or possibly one response.
And so a lot of this is, seems
to be actually the younger the patients are,
the better it works because the immune immune system is
probably more malleable at that time.
And so what we're doing right now,
I'll talk about the foods first, is we are doing a lot
of food, oral immunotherapy
where we are taking these patients
with severe food allergies, basically life-threatening to,
you know, peanut for example,
we are giving them about one 50000th of a peanut orally,
slowly increasing that over time.
And it's pretty, pretty amazing.
You can see the immune response pretty quickly like this IgG
four increasing pretty quickly after taking it.
And then you can see the IgE slowly coming
over down over time.
And, and so you'll, you'll notice these levels are changing.
And so this is something that is really on the horizon,
newer, newer therapies that we're doing.
And it works really well, especially the younger they are.
It works in adults too, but definitely better than kids.
And so, and then I can talk about environmental as well,
but do you have some questions
about the food allergies? Yeah,
- I, I just wanted to hop in and maybe ask for our audience,
'cause people maybe a little bit, you know, have a kind
of a broad base of understanding and,
and you know, as you're talking through th one,
th two response, just, I was wondering if we could kind
of paraphrase that for our listeners to kind of pick up,
I guess, do you think it's fair to say that, you know,
the body in some of our patients have learned to respond
with this sort of allergic anaphylaxis response
and with this strategy
of giving small doses over long periods of time
is kind of reprogramming that response,
so it does not respond in that way?
- Yes, yes. Basically, so IgE is,
so you can think of the like th two arm,
we really don't need the th two arm anymore.
And it's, it's a, it's a hyperimmune response, the IgE.
And, but unfortunately some people are,
are starting off at a young age going that route.
I mean, we have theories,
hypothesis why they're going that way.
Some, some genetic, some other exposures possibly.
But if they're starting to veer off that way, can we
decrease that, that allergic response?
And it looks like possibly we are, at least for the foods,
able to kind of revert that strong allergic response back
to a kind of a more normalized response.
And so that's kind of what this oral immunotherapy is.
- Excellent. And is there anything else that needs
to be given to kind of reprogram that response?
Or is it just kind of the, the frequent low dose that seems
to allow the body to have a, a reset
- Yep.
Frequent low dose with increasing, increasing amounts.
So eventually you'll get up to a higher
amount, but yeah, it normal.
I mean, they, there's people that looked at studies,
do you need to add other things?
You know, there was initial some data, some herbal,
herbal supplements maybe helped,
but subsequent studies haven't shown that to be beneficial.
You know, people are looking at other factors with it.
- Wow. So this sounds like something,
and I know we're gonna transition
and talk about environmental antigens in a second,
but this sounds like something that, you know, unlike, a lot
of times we read about new advancements that are being made,
it sounds like, you know, it's like stuff that is very,
very costly access to this is very limited.
Are some of these same challenges true when you're talking
about these kinds of therapies?
- Yeah, so in interestingly, so
the FDA, you know, needs to review things to see, you know,
are these safe and, and everything.
And, and the FDA process is long and it's expensive.
And so companies need to recuperate those costs.
So a company studied peanut flour
through processes
and they, they market it now called Peoria.
And so I, I was actually on the advisory board of them
and myself and some other doctors.
You know, we say, well, why,
why are these patients paying a thousand dollars when this
is just peanut flour?
You know? And some people want
that prepackaged flour, you know,
we can measure it ourselves a small amount,
but some, some institutions only allow FDA approved
products, and so they need that prepackaged dose.
And so some people will, will, you know, go through this
for peanut called palor expensive,
but it's, it works, but,
or you can do, you know what we measure out the doses.
- Hmm. Now if as we transition
to environmental antigens
or allergies, is that, is it very similar story
or is it more problematic
because we maybe have less control over
our environment than, than what we eat?
- Yeah, so, so the, the food allergens, it's pretty, I mean,
you can see clear as day, you know, a patient, you know,
we challenge 'em to, you know, a one liter of milk
and they have anaphylaxis
and we give 'em these small amounts and
after six months they're drinking a glass of milk.
We can see 'em in front of our face, say, Hey,
you, well, you're fine.
You know, you can go eat ice cream,
you can go eat cheese pizza.
You do what you want. You know,
whereas environmental is, you know, it's different.
You know, people have, you know, there's sneeze,
it's your eyes, we, you know, we can't, we can somewhat see,
see it, but it's not, you know, black and white difference.
We can see with that.
So with the environmental, it's,
it's an something called sublingual immunotherapy is
typically what is done with the oral route.
So same concept,
but basically giving small amounts of the, the food,
or sorry, the environmental pollen animal dust
mite under the tongue.
So there's a couple options to do.
Some companies have made them for dust mite,
a tablet called ra, two grass tablets, grass tech
and oral air, and then a ragweed tablet, rag tech.
Or you could go to some special compounding pharmacies like
our facility, or there's other ones that do compound these,
and they, you can get 'em underneath the tongue
and do those at home.
They, they work well.
Normally reduce symptoms by about, you know, depending on
what, what study look at maybe 50% reduction in symptoms.
So it's not, you know, a hundred percent, but,
- And what's the Venn diagram look like?
If we're talking about people that have allergies
to food allergens
and then people that have allergies to environmental, is
that, is that pretty overlapping
or is that, is that kind of more of a separate,
- Seems to be like eczema seems to be possibly like the,
the middle starting point of those, A lot
of kids have eczema and we think,
- So dry, dry skin, - Dry open, rough skin.
We think because it all starts with
that maybe these allergens, food
and environmental are coming through that skin
and citing this th two process
that's starting this allergic pathway is
kind of where we think.
And so that's why we always try to tell this patient
with eczema, try to get a real good skin barrier
early, prevent that.
But there's some patients that have no eczema
and all of a sudden get environmental allergies,
get food allergies, get asthma.
But I mean, my specialty is asthma, environmental allergies,
food allergies, and eczema.
And I see a lot of patients with all of it.
A lot of patients have more than one of 'em, not everybody,
but a lot of 'em have a couple of those conditions together.
- And is, is your treating one is, is it a true saving
to say like, you know, if I'm having,
if I have a milk allergy and you're desensitizing the,
or retraining my th two response,
and I also have other allergies,
like maybe environmental allergies d does that,
is there a crosstalk there where I'm kind
of decreasing my overall th two allergic response?
Or is this something that the body has
to learn like per allergen?
- So it is a good, good question.
Typically for the foods, it's per allergen.
Interesting though, along that line,
so allergy shots have been around for over a hundred years,
and same concept, give injection of a little bit of
what you're allergic to for environmental allergens, not
for foods, but environmental allergens give a little
bit more and more, more.
In the United States, we typically try
to find everything you're allergic to, like Timothy grass,
short, ragweed, birch, and we put that in the shots,
and then you get shots of those.
However, what I hear is in Europe,
they just say, okay, you're allergic to 30 things,
we're gonna put the five major things in
because your overall allergic response is gonna drop.
Hmm. So, so there is, there's definitely some data
that shows yeah, your total overall allergic response is
gonna drop even if you don't target those for environmental.
But foods, we aren't seeing that right now.
- Well, it's interesting to see that separation.
You know, I, I really appreciate you highlighting this
for our, our audience.
And as you know, we have a, a strong number
of audience members that are joining us from the lab
medicine perspective.
And this podcast is really about kind
of creating these bridges
and helping laboratory medicine in the clinical practice,
sort of understand how each other works.
And I was wondering if you might share, you know,
maybe some ways that in your practice you rely upon
or use lab testing to support the, the care
of your patients.
- Yeah, so one big thing is,
is there's a condition called oral allergy syndrome,
otherwise known as food pollen syndrome.
It's very common. I guarantee you
that some people listening here have it, I have it myself.
People probably have it, and they don't even,
didn't even realize it.
But it basically is people who eat
like raw apples or raw carrots, raw celery, raw cherries,
and they eat 'em in their mouth kind of itches,
or they might get a little bit of swelling of their tongue
or, or their, their lips or maybe a few hives.
And the next time they eat it, they don't notice it,
and then next time they do.
And so they're very confused
and they're saying, you know what, what
is going on with this?
And normally what that is, is,
the way I explain it is if people are allergic
to certain pollens, if you looked under a microscope
at those pollens, they have certain molecules in them
in those fruits
and vegetables, they also have the exact same
molecules in them.
And because of that, then your body is saying, Hey,
you just ate some pollen and cause the itchy mouth,
but the molecules are weaker.
And so when the acid and stomach breaks 'em down,
you don't have those full body
reactions and also cooking it.
So somebody might eat like a, a applesauce and they're fine,
but a raw apple, they have problems.
And so in interestingly, the lab is very helpful in,
in telling us it's called component testing.
So we can do IgE component testing, which is very useful in,
in helping us identify whether these reactions would
be severe or not.
The particularly peanut
and tree nut is a big one where patients come in
and they say, you know, I've never had a peanut,
and all of a sudden I had it
and my lip felt funny, my tongue thinks was swelling.
And we say, okay, can, can we tell, can we tell if
that is gonna be a severe reaction or not?
And yes, we can through, through the lab medicine,
and so you can do those tests
- Phenomenal.
So you don't have to actually expose somebody to it again,
you can kind of, I guess,
look in a more safe way, it sounds like.
- Yes, there is.
Speaking of that, I have not done much of this,
but there is a lab test called a a, a
basophil activation test, BAT.
Only certain labs have it,
but basically it's basically supposed to
see if a patient would have a severe reaction to a, a food.
So let's say you did a IgE to egg before
and level was, you know, 0.4 or five
and you say, gosh, I I don't really
wanna challenge this kid.
This kid is, you know, not a very healthy kid.
I don't really wanna challenge him, but I don't wanna
make all these avoidance.
There is a way to do this
where you basically mix the patient's blood with
the food agen
and you can see if these basal fills are activated.
I know only certain places have that test,
but that is, is something that's probably gonna become more,
more useful as, as the studies go on to see how, how,
how beneficial this test is.
- Yeah, it's wonderful to see And,
and to highlight for our, our listeners, I wanna kind
of close out this interview, maybe just asking again,
in recognition of, of this being asthma
and allergy month, like what do you think kind
of what's just over the horizon in your field?
You know, like, in other words, h
how do you think you'll be practicing
differently in 10 years?
- Yes, so the biologics medicine,
all the monoclonal antibodies is really,
really taking over our space, very targeted medicine.
And so, you know, lab medicine will be useful in that,
that aspect in that, you know, we need to find which,
which are the biomarkers that we're targeting.
And so I think that's really gonna be, continue
to be the wave of the future.
- That's awesome to hear. And I mean, yeah, absolutely.
That's something that we're familiar with in,
in laboratory medicine
and how we think about different interferences
or what does that mean for the other tests
that we're looking at and measuring.
So thanks for rounding with us, Dr. McMahon.
- You're welcome. - And thank you
to listeners for joining us today.
We invite you to share your thoughts
and suggestions via email.
Please direct any suggestions to MCLeducation@mayo.edu
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