The Allergist
Welcome to your allergy lifeline..."The Allergist." A show that separates myth from medicine.
Every episode of The Allergist is designed for YOU – the medical professional aiming to stay on the cutting edge of allergy care. We'll clarify, correct, and, most importantly, contextualize the latest evidence.
The Allergist
Highlights from the 2025 allergy literature
Use Left/Right to seek, Home/End to jump to start or end. Hold shift to jump forward or backward.
Keeping up with the allergy literature can feel like a second job layered onto an already full clinic day. Between evolving guidelines, expanding biologic options, and long-held assumptions quietly being challenged, it’s hard to know which papers are worth slowing down for. This episode takes a deliberately selective approach. Dr. David Khan — chair of the American College of Allergy, Asthma, and Immunology literature review — walks through five papers from 2025 that stood out not because they were flashy, but because they asked practical questions allergists actually wrestle with in clinic.
Timing of repeat epinephrine to inform pediatric anaphylaxis observation periods: a retrospective cohort study
For most children treated with epinephrine, prolonged emergency department observation may be unnecessary, with two hours appearing sufficient unless cardiovascular features are involved.
Two-year data of tapered dupilumab shows high effectiveness in chronic rhinosinusitis with nasal polyps with NSAID-exacerbated respiratory disease
In real-world practice, most patients with CRSwNP maintained excellent control while spacing dupilumab doses far beyond every two weeks, challenging long-term fixed dosing assumptions.
Remibrutinib and chronic spontaneous urticaria
This trial marks a major shift for CSU, introducing an oral, targeted option that delivers rapid symptom control and meaningful rates of complete remission.
A randomized trial comparing direct challenges to penicillin skin testing for outpatient low-risk penicillin allergy evaluations in pregnancy
For pregnant patients with low-risk penicillin allergy histories, direct oral challenge proved safe, efficient, and more streamlined than traditional skin testing.
Age differences in inducible laryngeal obstruction in adult populations
Inducible laryngeal obstruction appears common in older adults, often presents more subtly, and frequently masquerades as asthma or anaphylaxis.
Taken together, these papers reflect a broader shift in allergy care: less reflexive caution, more precision, and a growing willingness to question long-standing habits when better data emerge. Whether it’s shortening observation times, tapering biologics, simplifying drug allergy evaluations, or recognizing long-ignored mimics of allergic disease, the 2025 literature nudges allergists toward care that is more precise, less reflexive, and still clinically vigilant.
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, and this is The Allergist, a show that separates myth from medicine, deciphering allergies and understanding the immune system. In 2025, the guidelines for chronic urticaria were updated, a DEL5 for EOE was published, we looked at how far we've come for food allergy prevention, and perspectives on everything from asthma, anaphylaxis, to HAE, you basically name it, there was a publication about it. It's a lot, and for anyone in practice, rather overwhelming to deal with. There's a volume to daily practice, and then add for it this evidence that continues to change, the guidance that continues to change. So did you know that in 2013, the Oxford Word of the Year was FOMO, Fear of Missing Out? It was actually coined by Patrick McGinnis in 2004 in an article for the Harvard Business School student newspaper. The concept of missing out is actually ancient, but it gained significant traction and widespread use through the rise of social media, and a particular platform that actually was coincidentally started on that same year, in 2013, really launched this word into fame. Now it turns out that the 2025 Word of the Year, if you haven't heard about it yet, is actually rage-baiting, defined as content that is frustrating, offensive, or provocative to trigger strong emotional responses online, drive traffic and comments. And I'll clarify right now that the purpose of today's episode is to help address concerns of the former rather than drive the latter. And with that, I actually am super excited to introduce today's guest. He's the chair of the American College of Allergy, Asthma, and Immunology Lit Review for the last 10 years. If you haven't had the chance to attend this day, it's a glorious day, but he gives the annual lecture covering the best articles. So I thought he'd be actually the best person to get to do today's episode. It's my pleasure to introduce Dr. David Kahn. He's a professor of medicine and pediatrics at the University of Texas Southwestern Medical Center in Dallas. He's been the program director of the fellowship program at Southwestern for over 27 years. He's the past president of the American Academy of Asthma, Allergy, and Immunology, and is the past recipient of numerous awards, including the Distinguished Clinician, the Distinguished Fellow, and Educational Council Awards. He's an associate editor of the Journal of Allergy and Clinical Immunology in Practice, so he gets insights into coming up publications all the time. But Dr. Kahn himself is an author and a contributing author on more than 300 publications, abstracts, and book chapters. His research interests have focused on drug allergy, refractory chronic urticaria, and asthma, with comorbid mood disorders. Thank you, Dr. Kahn, for joining us for today's episode on highlights of 2025. It's a lot, and you said yes. So welcome to the podcast.
Dr. David Khan:Well, thank you so much. It's a pleasure to be here, and I'm glad we're not talking about online rage.
Dr. Mariam Hanna:I just thought it was an interesting comparison, though, as to where we are. I didn't include what the runners-up in terms of word of the year were, but for those listeners that are interested, do look it up because those are interesting terms as well. This episode is a slightly different format in that I reached out to you earlier and said, give me your top five articles and let's go through them. And as I'm looking through your bio and things that you're interested in, I'm also interested in your choices for these top five articles. So we're going to cover one at a time. It's a lot of content. So for our listeners that really want to dig into the particular articles, they're all linked with today's episode so they can read them in depth if they haven't already. But let's start with your first article choice, if you can give me the title of that and why it was your first choice.
Dr. David Khan:Yeah, sure. So the first article I selected was entitled Timing of Repeat Epinephrine to Inform Pediatric Anaphylaxis Observation Periods, a Retrospective Cohort Study. This is by Tim Dribben and colleagues. So I chose this article because it deals with an important clinical question. That is, how long should children need to be observed in the emergency department after treatment with epinephrine?
Dr. Mariam Hanna:Yeah. And what did this study show in particular?
Dr. David Khan:Yeah, so I think this kind of deals with this issue of biphasic anaphylaxis. We know the rates are pretty variable and there's not a lot of great clinical data on children. So this study really aimed to determine what's the incidence rate and timing for repeat doses of epinephrine. So this is a retrospective study involving kids 6 to 17 years. They went to one of 30 ED departments in the U.S. and one that was in Canada, and they were eligible if they presented to an ED after an acute allergic reaction that was treated with epinephrine. And the primary outcome was the time between administration of the first and the last dose of epinephrine. So it was a pretty big study they had in 5,641 kids. About 4,000 of those had respiratory envelopment without cardiovascular. They had a more severe group that had about 500 that had cardiovascular involvement. Food was the main trigger. Over 80 percent of the kids had food as a trigger for their reaction. And when they looked back to see how many actually met criteria for anaphylaxis, about 88 percent. The rate of biphasic anaphylaxis in this cohort was 1.5 percent. Now, again, their main outcome was looking to see when they got that last dose of epinephrine. And answering the question, how long do you really need to stay in the ED? And it turned out that 95 percent of these kids could have been safely discharged at two hours. If you went to four hours, you got to 98 percent. Now, they did look to see, was there a subgroup that was more likely to have repeat doses? And those patients who had cardiovascular involvement had a higher rate of repeat epinephrine after two hours, suggesting that they might need a longer observation period. So the kind of key take-homes for this is that kids treated with epinephrine either before or in the ED for an allergic reaction, a two-hour waiting period seems to be sufficient for most of them. If they have cardiovascular involvement, a four-hour observation period is better.
Dr. Mariam Hanna:Okay. Fair enough. And this biphasic anaphylaxis rate shown in this trial, how does this compare to other rates of biphasic anaphylaxis that typically are coded in the literature?
Dr. David Khan:Yeah. So there's a wide range of biphasic rates, up to about 20 percent, a little higher when you look at kind of prospective studies. It also determines, like, what do you call a biphasic reaction? Because they actually looked at that, and there were definitely higher rates of biphasic allergic reactions, but when they went to those that had anaphylaxis, it was a lower percentage. And so it gets into the semantics that you might treat someone who has, like, a recurrence of their hives with epinephrine, but, you know, is that anaphylaxis? Not necessarily. So I think it is kind of in keeping with more recent literature that's bringing that number a little lower than it used to be.
Dr. Mariam Hanna:No, absolutely. And how does this kind of impact day-to-day management? So when we specifically, like you mentioned, looked at amount of observation in hospital, two hours versus four hours, could this be applied to in-office management or, as we've started talking about, home management of anaphylaxis?
Dr. David Khan:Yeah, I think in the office, there was a study from Ann Alice that looked at those patients that had gotten treated very quickly and responded very robustly with epinephrine, and it was very rare for those patients to have biphasic reactions. And I think, like, in the allergist office, we're on top of our patients so quickly with epinephrine that we tend not to see as much of these biphasic reactions as maybe out in the wild, so to speak. So I think this is a reasonable observation in the office as well. For home administration, I think this is becoming, again, we're suggesting to patients to use their epinephrine earlier, not waiting for them to have full-blown anaphylaxis. And so I think this is something that can also be considered in terms of how long do they really need to wait before they need to go to the ED, because we don't, that's the message that we're trying to break, is that just because you use epinephrine, you don't need to go to the ED because that oftentimes prevents people from ever using epinephrine in the first place. So I think there are some lessons that can be adapted, and if we look at what the guidance was in the 2020 practice parameters, they suggested that after an hour of being asymptomatic, there was really very little payout waiting beyond that, unless you had severe anaphylaxis, required multiple doses, et cetera.
Dr. Mariam Hanna:Absolutely, absolutely. And then to extrapolate a little bit more, what about the adult population? This was a pediatric study. Would you foresee the same kind of data could be shown in adult patients?
Dr. David Khan:Yeah, I think there's actually probably a little bit more robust data that kind of informed the practice parameters. There was more, I would say there was more adults in that systematic review and meta-analysis. So I think this, and it's very much in line with that two hours versus one hour, you're kind of in that same range. So I think we can be confident for most patients with anaphylaxis that they don't need to be observed for four or six hours overnight, et cetera. If they respond quickly, they don't have cardiovascular involvement, don't require multiple doses, all those kind of factors.
Dr. Mariam Hanna:Awesome. And an exciting like turn or continuing increase in evidence on anaphylaxis management as we get into more usage of epinephrine and encouraging safety of just treating anaphylaxis. OK, we'll leave anaphylaxis alone for a moment and move on to the next article. Your next choice, Dr. Kahn.
Dr. David Khan:Yeah, so the next article is entitled Two-Year Data of Tapered Depilumab Shows High Effectiveness in Chronic Rhinosinusitis with Nasal Polyps with Nonsteroidal Anti-Inflammatory Drug Exacerbated Respiratory Disease. Quite a mouthful there.
Dr. Mariam Hanna:Mouthful, yeah.
Dr. David Khan:So I chose this article because I have a number of patients on depilumab for nasal polyps like many of us do, and they've done very well. And the question is, how long do they need to stay on this every two week dosing? And can we extend it? And how far can we extend these intervals? So I thought this is a very clinically relevant study.
Dr. Mariam Hanna:Absolutely, and like also the cost difference of being able to taper these patients off. So I thought it was a really intriguing article to look at as well. What was shown in this study? If you can walk us through that, please.
Dr. David Khan:Yeah, of course. So there's not a lot of data looking at little long term use, but also tapering this population. So this was a real world prospective observational study that looked at the possibility of dose tapering and clinical effectiveness of depilumab in CRS with nasal polyposis with or without the NSAID exacerbated respiratory disease or AERD, you know, whatever terminology you want to use. They used a database from the Netherlands and they had baseline data at week zero, 24 and all the way out to 96 week data for some participants. So the study involved almost 300 patients. About a third of them had the NSAID exacerbated respiratory disease. Those patients, as you might imagine, tended to have longer disease duration. But in general, we're talking 10 to 15 years of disease in both of these cohorts. The AERD patients had a little bit more asthma, but asthma was pretty prominent in both. So what they found, the outcomes in terms of they did look at several different outcomes. They looked at the SNOT-22 scores. They looked at asthma in terms of ACT scores. They actually had a scratch and sniff score. And they did nasal polyps scores by endoscopy. Everything got better. And, you know, these are, we know this, the drug works, right? What I thought was interesting was at two years, the nasal polyps score was actually better than it was at 24 weeks, which is interesting because we think that all that effect happens very quickly, but maybe things get even better long term. Now, again, the tapering is what caught my eye about this and how they did this was after 24 weeks of dupilumab therapy at the every two-week dosing, if they had a moderate to excellent control or responses, then they extended that interval. And every 24 weeks, if they were doing well, they'd extended it a little further. So they first went from two to four weeks, then six weeks, then eight weeks and all the way up to 12 weeks. They never stopped anybody, but they went as far as 12 weeks if they could. And I thought this was astounding. 91 to 95 percent of the patients were able to be tapered beyond that every two-week dosing. So that's the vast majority of participants, right?
Dr. Mariam Hanna:Huge number.
Dr. David Khan:About 40 percent got to every four to six weeks and about 50 percent got to about eight to 12 weeks. Now, if we look at those that got to that 12-week mark, it was much higher if you didn't have AERD. So those patients may not be able to be as successful as tapering out long term. But yeah, so this is, I thought, a remarkable observational study really suggesting that tapering is oftentimes quite successful.
Dr. Mariam Hanna:Yeah, tapering to some degree in almost all patients with the more severe phenotype maybe not being able to taper as far out. Did these patients relapse? Did they mention that at all in some of these? Did they have to go back up for any of these that were tapered?
Dr. David Khan:You know, they didn't really comment about those patients that weren't able to or had to go back. It was just like how many kind of could stretch out. But that's a good question. How many had went to eight or whatever? I assume there's going to be, and we see this in clinical practice, right, that you stretch out so far and, oh, I'm starting to have a little problem. But I think, again, the message is that every two-week dosing may not be necessary for most of the participants.
Dr. Mariam Hanna:Yeah, absolutely. And next steps in terms of biologics in general in the nasal polyps space, could we like extrapolate and say that potentially remission or decrease need for frequent administration could be considered with other biologics? Or is this unique to how this drug works, dupilumab specifically?
Dr. David Khan:I think this is a great question for the whole biologic space, no matter what the disease is, right?
Dr. Mariam Hanna:Right.
Dr. David Khan:And I'm sure it's not unique to dupilumab. I think it'll be interesting to see what happens. I think with tezapilumab now being approved for nasal polyps, and that appears to be a little bit more effective than some of the other biologics, and it'll be not necessarily more effective than dupilumab, but that same high degree of efficacy. So I think that'd be really interesting to see what the long-term data is with that. And I think we need to look at this for other disease states for sure.
Dr. Mariam Hanna:Yeah, I now feel like it's not just about discussing biologics and how well they work. It's how can you taper or what's the least frequent dosing schedule that we can get patients on. So it's an exciting part of this discussion around biologics. OK, speaking about biologics, we're going to go into CSU therapy, and this leads us into your next article choice. And I recognize that you also like research around chronic urticaria, but you included one article here. Please tell me this next article choice that you've selected.
Dr. David Khan:Yeah, sure. This one, fortunately, has a much shorter title. Remy Brutonib and Chronic Spontaneous Urticaria by Metz and colleagues. So I chose this article because it covers a novel therapy for CSU. And then the timing turned out to be perfect because it was FDA approved a week before the meeting was, so there was a lot of excitement about this paper for sure.
Dr. Mariam Hanna:So lots of hype about Remy. What did this study particularly show in the chronic urticaria space? And as a sidebar, people are either incredibly passionate about chronic urticaria or are like, what's the big deal? It's just a bunch of hypes. But yes, go ahead. Tell me some more.
Dr. David Khan:Yeah, I'm in the passionate category. But I think as we have more therapeutic agents available, I think there will be more people who will be excited about managing CSU. That's clearly been the case that we've even with omelizumab where before everyone hated seeing urticaria patients. And now it's, oh, I've got a lot of things up my sleeve, so it's not quite as bad. But getting back to the study, this is a large group of studies, two parallel studies called REMIX-1 and REMIX-2 involving 925 adults. And two thirds of them got remibrutinib, which is an oral BTK inhibitor, 25 milligrams twice a day, and a third got placebo. And the primary outcome was the change in their urticaria activity score at seven at 12 weeks. And it clearly met that outcome. If we look at those who had well-controlled CSU, remibrutinib versus placebo, you clearly saw differences throughout the study. The main adverse effect was petechiae. And this is now in the labeling about that they talk about bleeding risk. And this is mainly mucocutaneous and mainly petechiae. And in this trial, it was a little under 4 percent versus placebo. If we dig into, well, well-controlled, but what about complete control? And here they found about a third of participants at that 12-week mark were at complete control. And interestingly, just last month in Jackie, in PRESS, they released the 52-week data. And here what they did was they crossed over those that were in placebo to remibrutinib. And at 52 weeks, there was about 42 to 45 percent of participants that had complete control, which is I think that's pretty impressive data.
Dr. Mariam Hanna:Yeah, for urticaria, absolutely. That's very impressive. How does Remi, a BTK inhibitor, differ in terms of pathway versus our traditional omalizumab or dupilumab pathways that are being used here?
Dr. David Khan:Yeah, so very different. So as allergists, we're very familiar with with BTK when we think about immunodeficiency. And if you don't have BTK when you're born, you lack B cells and you have agammaglobulinemia. So we're like, why would you want to knock out BTK? But, you know, once you have a little bit of it, then it's not it. You're not knocking out B cells completely. And BTK inhibitors have been around to treat cancer. But many of these early ones were not very selective and had a lot of off-target effects and off-target serious adverse effects. Remibrutinib and some of the other newer ones that are being looked at for CSU are very selective BTK inhibitors. And so they have less of these off-target effects. But why BTK is important for urticaria is that in addition to being in B cells, it's also in mast cells and basophils. And it plays an important role in downstream signaling from the high-affinity IgE receptor. So it will help inhibit that mast cell activation release of all these mediators. And that's a theory. And if you like the different type 1 or type 2B autoimmune, whichever theory you like, BTK would be involved with both of those. So it does seem to play an important role in the pathogenesis of urticaria. So it makes sense that this would be effective.
Dr. Mariam Hanna:It makes sense. Now, walk me through the treatment algorithm now that we have for chronic urticaria. You mentioned multiple things up our sleeve. Where is Remi going to fit into these guidelines?
Dr. David Khan:Yeah, it depends like what guidelines we look at. If we look at the international guidelines, they put omalizumab, dopilimab and remibrutinib, basically any of the things that are FDA or I guess EU approved, whatever, all on a level playing field. Our practice parameters workgroup, we had our kind of almost next to final meeting very recently. And so it'll be a little bit different than I would say the international guidelines. And you will all be seeing these probably in a few months because it goes out for public comment. But I think part of the decision making, we look at, of course, effectiveness, but also safety. And here, compared to, say, omalizumab, which has been around for decades, we don't have a long term safety profile with remibrutinib. So I think that was the thing that maybe made it, pushed it back. But I think we still clearly have several things that we have recommended, some with stronger recommendations than others.
Dr. Mariam Hanna:Yeah, I like foreshadowing about things to come, exciting things to come.
Dr. David Khan:All right.
Dr. Mariam Hanna:I won't push you too much. I guess one of the things that someone like me looks at with Remi and how its mode of action is different from the other biologics that we have is why wouldn't we consider combining in different types or like a reducing frequency of dosing of one to get efficacy like these dual action or the best of both worlds? Can I look towards that in the future without revealing what's happening in this practice?
Dr. David Khan:Yeah, I think, yeah, this this concept of combining agents is very interesting. And whether that will be ever practically possible, it's hard to say. I can tell you, we remarkably had a patient who was on omalizumab and was kind of like a partial responder who got approved for remibrutinib. And so this person is on dual therapy. We'll see if they seem to have responded. But it is interesting. And I think from a theoretical standpoint, it does make some sense. But whether that's going to be practical, I think it's going to be a harder sell for sure.
Dr. Mariam Hanna:Right, right. Theory and practicality. OK, yes, yes. Very good point, Dr. Kahn. All right. We're going to move on to our fourth article choice covering a special population. Your next article choice, please, Dr. Kahn.
Dr. David Khan:Yeah, so as mentioned, I like drug allergy as one of my other interests. And so this next article is entitled A Randomized Trial Comparing Direct Challenges to Penicillin Skin Testing for Outpatient Low-Risk Penicillin Allergy Evaluations in Pregnancy by Patralo et al. And so I chose this article, I like drug allergy, I like penicillin allergy delabeling specifically, but also because it's a randomized controlled trial in pregnant women with drug allergy. I mean, you can't find a more rare study than this. So I think it's credit for these investigators for doing this study for sure. So I'll walk you through this. As we know that penicillin is a first-line therapy for neonatal group B strep infection. And if you have this penicillin allergy label, moms receive longer antibiotic therapy, there's higher risk of C-section, baby stays in the hospital longer. So there's lots of reasons to consider delabeling. So this study basically compared direct oral challenge versus the reference standard skin testing and challenge during pregnancy. So who was low risk? They had their own low-risk definition. They said it had to be more than five years ago, cutaneous only or unknown. If they had angioedema, anaphylaxis scars, they were excluded. And so the direct challenge was 40 milligrams of amox and 30 minutes later, 400 milligrams and then 30-minute observation. So you're done in 60 minutes. With the skin test, it was pre-PENG-G. And then if that was negative, they gave them 400 milligrams of amox with a 30-minute observation. And what did they find? All 70 of the women who got direct challenges passed it, 100 percent. The skin testing group, there was 93 percent pass. So statistically, it was the same, but clearly there was a trend towards a little bit more effective delabeling with direct challenge. Direct challenge was faster and it was less expensive than skin testing and challenge. So again, I think this really does suggest in this randomized controlled trial, similar if not perhaps better efficacy and safety of direct challenge when we're doing delabeling in pregnant women.
Dr. Mariam Hanna:And were these women undergoing challenges at the time of labor and delivery or were they GBS positive? And that's why we were doing their direct challenge then? I've heard others of other camps that say, well, if they're not GBS positive, we can postpone this until postpartum.
Dr. David Khan:Yeah, so this they were not like necessarily all GBS positive or anything like that. And they were challenged at any trimester. Some were done in the first, some were done in the second, some were done in the third trimester. So and now the American College of Gynecology does recommend penicillin allergy evaluations in pregnant women. So this is something that I think we need to get on board with for sure.
Dr. Mariam Hanna:OK, now, low risk penicillin allergy, is there outside of pregnancy or any like, is there ever an indication to do a penicillin skin test nowadays, like for these low risk stories?
Dr. David Khan:Yeah, I would say no. And I think what happens when you do skin testing in the low risk individuals is where you end up with false positive skin tests. So I think it impedes your delabeling process. I think the only time we really do it are those patients who are just so worried and they're like, oh, gosh, I know I'm going to have something horrible happen to me and I'm so worried. And then doing the skin testing can sometimes reassure patients. So that's about the only time that we end up doing skin testing is for reassurance purposes. But most of the time, it's not necessary, certainly not for kids at all. And I think the evidence is pretty strong that we don't need to do it for adults either.
Dr. Mariam Hanna:Fair enough. And then you're doing it and really hoping for a negative for reassurance purposes.
Dr. David Khan:Absolutely.
Dr. Mariam Hanna:Moving on to our last and very interesting article choice, Dr. Kahn, what's your final article choice for this year?
Dr. David Khan:So this article is entitled Age Differences in Inducible Laryngeal Obstruction in Adult Populations. And I chose this article because I see a lot of older adults with inducible laryngeal obstruction and there's not as much literature on these older adults.
Dr. Mariam Hanna:OK, but first, what is inducible laryngeal obstruction?
Dr. David Khan:Yeah. So ILO, that's the new term for what we all know as VCD or vocal cord dysfunction.
Dr. Mariam Hanna:See, I knew it. It was a new acronym.
Dr. David Khan:I'm like, what is this new disease?
Dr. Mariam Hanna:All right.
Dr. David Khan:The reason is that you can have laryngeal obstruction when it's not involving the vocal cords like the retinoids and things like that. So something that's not new, it's just another term. And this terminology is changing all the time. But ILO is the term of the year for now.
Dr. Mariam Hanna:And a more appropriate physiologic description of what is happening. OK, so how is this diagnosed?
Dr. David Khan:So I would say most of the time we diagnose patients clinically. But obviously, if you can, laryngoscopy is the definitive way. And this can sometimes be done, well, if they're symptomatic, if you catch them when they're symptomatic or you're trying to provoke them, that's how we confirm the diagnosis. But I would say in clinical practice, majority of patients, we get the history, this sounds like it, we're going to manage you as if.
Dr. Mariam Hanna:OK, and what did this particular article show, now that I'm all up to speed on ILO?
Dr. David Khan:Yeah, so this is from the University of Nebraska, and they actually have a registry of patients that they've evaluated for ILO. And they confirmed this through laryngoscopy with methacholine or exercise provocation. And so they looked at these patients and they stratified them by age. And what they found, they had about 67 subjects. The median age actually turned out to be 50. 82 percent were women. And then they looked at those under 50 and over 50, and there were about 31 in the under 50, 36 in the over 50. So if you look at the younger participants, these are the ones that we classically think about VCD-ILO. They had lots of different symptoms, more anxiety. Interesting, just walking or going up the stairs was a triggering factor for them. They had lots of triggers. On the other end of the spectrum, the older participants didn't report as many symptoms, didn't have as many triggers, et cetera. All of them were predominantly women. They tended to be higher BMI. What was also striking, and I think this is something that we see as well, is the intubation history. 61 percent of these people had been intubated previously. So that's always a red flag. And I think in my personal opinion, those have had, anybody who's had multiple intubations for quote unquote anaphylaxis, you really need to be thinking about this disease. Now, one thing that we've all been taught is that if you do inspiratory loops, you'll see this flattening of the inspiratory loop, but only a third of them have that, so you can't really rely on spirometry to diagnose ILO. When you looked at the anxiety, again, that was a little higher in the younger population, but the classic symptoms, throat tightness, difficulty getting air in, we saw that across the spectrum.
Dr. Mariam Hanna:And in this study, they were also talking about patients with a positive methicoline also still having ILO. I find that particularly challenging population when you're dealing with their asthma and ILO. Is that fair to say?
Dr. David Khan:Yes, so the methicoline was not necessarily a positive challenge per se, but it provoked them to have the ILO. Now, you can definitely see patients, and this is what like a lot of the older studies looking at as ILO as a manifestation of asthma, and there are patients who have legit asthma and have ILO and trying to differentiate the two of them. And most patients can tell you, oh, I've got this type of asthma, and then I've got this other kind of sudden asthma, and then it's, oh, well, that isn't really asthma, and you can work through it. But the things that we now recognize is that ILO also is in the differential diagnosis for non-asthma things. So, we see a lot of patients who think they're having allergic reactions to drugs, and in fact, it's this. We see patients who think they're having allergic reactions to foods, and it's this. So, in the context of anaphylaxis, this is a common mimic of anaphylaxis, much more common than I think is really appreciated, especially in the older population.
Dr. Mariam Hanna:Absolutely. So, this information, you've already mentioned how it can be implemented into practice, particularly for our older patient population. It's a very interesting study and an awesome way to wrap up your 2025 article picks, Dr. Kahn. Thank you so much for doing this. All right. We're at the moment where now I'm going to ask you to wrap up all of 2025 and all of today's messages into three key messages to impart to patients and physicians on today's topic, the 2025 top articles by Dr. Kahn. Over to you. Yeah. So, my top three first. Most patients with CRS with nasal polyposis can taper to pilumab with continued good control, even out to every 8 to 12 weeks. Number two, remibrutinib, a selective BTK inhibitor, is the first oral targeted therapy for antihistaminofactory CSU, has a rapid onset of action and another alternative for our patients. And number three, direct challenges for pregnant women with a low-risk penicillin allergy history is likely the preferred option for delabeling and should be scheduled well in advance of their due date. Wonderful. Thank you, Dr. Kahn, for joining us on today's episode of The Allergist.
Dr. David Khan:Thank you so much.
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