Neha Pathak, MD, FACP, DipABLM: For most of us, fatigue and joint pain are easy to dismiss: a rough week, getting older, stress. But for Candice, those symptoms were the beginning of a years-long search for answers.

Candice Pauley: Around 2019, I started to notice some increased fatigue. I'd lived with joint pain since I was in high school, but it would be intermittent, and this was constant, and I couldn't make it go away.

Pathak: But from there, symptoms escalated.

Pauley: And then the real issue became my GI symptoms, extreme pain after eating. So I finally went to the doctor, and I was like, "I don't know that it's normal to be laying on the floor crying because my stomach hurts so much."

Pathak: Her doctor began ruling out the usual suspects: lupus, MS, thyroid disease.

What turned up instead was something far less familiar. A CT scan flagged severe changes in her hips, and then, not in a phone call from her doctor, but in an app notification, came a word Candice had never seen before.

Pauley: And there was this word, systemic mastocytosis, that I had never heard of. And so when you get that, of course, your first reaction is to Google things, and the first thing that pops up is survival rate, and it was five to seven years.

Of course, I was panicked. That was a really terrifying thing to see.

Pathak: Indolent systemic mastocytosis, or ISM, is a rare immune disorder in which abnormal mast cells, the body's own frontline defenders, multiply out of control and accumulate in organs like the skin, bone marrow, and gut. It can look like dozens of other conditions, which is part of why it often goes undiagnosed.

Pauley: It's missed for years and sometimes decades because we're looking at these tiny little pieces of the body instead of the person as a whole.

Pathak: For Candice, building the right medical team took months. Eventually, she found a hematologist who not only recognized the disease but knew about a newly approved targeted therapy she qualified for.

Slowly, a clearer picture emerged.

Pauley: In general, I describe it as an allergic disease, but it's also a chronic cancer. But the thing that I really focus on is that I can live with the disease, and it is unlikely I will die from it.

Pathak: That distinction between living with and dying from turns out to be one of the most important things a patient with ISM can learn.

But getting there requires something most patients don't have at the start: a diagnosis, a team, and a community that understands what they're going through.

Pauley: Being able to go somewhere where I'm fully understood is like a big weight lifted off your shoulders.

Pathak: But for every Candice who finds her way to answers, how many are still out there, dismissed, misdiagnosed, searching symptoms online at midnight?

How does a disease this systemic hide in plain sight for so long? And what does treatment actually look like when the condition touches so many organs throughout the body? I'm Dr Neha Pathak. The answers when Health Discovered returns from a short break.

To learn more about ISM, I sat down with Dr Aaron Gerds. He's an associate professor of medicine in hematology and oncology at the Cleveland Clinic Cancer Institute and a principal investigator in clinical trials that led to developing novel therapies for patients. For Dr Gerds, research isn't a last resort.

It is the standard of care, and in a disease this rare, that mindset might be exactly what patients need. Welcome to the WebMD Health Discovered podcast, Dr Gerds.

Aaron Gerds, MD: Thanks so much for having me. It's a pleasure to be with all of you today.

Pathak: Well, I am so thankful to you for your expertise in our topic for today.

But before we begin exploring that, I'd love to ask about your own health discovery in your research or your work with patients. What questions led you to the work that you're doing today?

Gerds: Yeah. In cancer medicine, particularly rarer diseases like mastocytosis and MPNs, it's almost a necessity to take care of these patients.

It's not like treating hypertension. Not that there shouldn't be research in hypertension, but hypertension is so prevalent, and there are a lot of medications to treat it. But in these rare diseases, there are very few medications available to treat these patients. And so we need to have more options for our patients, and we need to keep getting better options.

So to me, in what I do, I really see clinical trials as the standard of care, not just something we do after standard of care. I believe it is, in fact, the standard of care. And so really, it's natural that we extend into these trials to make patients' lives better. And by doing so, I mean, even in my relatively short career, I've seen so many things come along, improving everyday lives of patients.

It's just been a remarkable experience.

Pathak: That's really powerful. So let's start by taking a step back and explaining what indolent systemic mastocytosis is.

Gerds: Yeah. So mast cells, they're these white blood cells. They're of the myeloid lineage relative to the lymphoid lineage, and they're full of these granules.

They're kinda... You know those really popular gummy Nerds nowadays? They look like that, if you will, under a microscope. And those granules are filled with all these immune factors and kind of allergic factors, right? Like things like histamine and tryptase and stuff. And so these mast cells, due to a mutation, can increase in number and grow out of proportion for what your body normally needs.

And so you picture this load of mast cells, and many of the manifestations we see in the disease, systemic mastocytosis that is, are a result of these mast cells degranulating and causing the symptoms. And they kind of got a hair trigger. They'll degranulate at the drop of a hat or for no good reason at all sometimes.

There's a classic kind of story that you read about in textbooks. Quite frankly, I haven't seen it in real life, but it definitely can happen where, you know, a patient has anaphylaxis to a bug bite, particularly a bee or a wasp, and that can ultimately lead to a diagnosis of systemic mastocytosis.

Not that every bee or wasp sting resulting in anaphylaxis is systemic mastocytosis, but it just kind of gives you a sense that there's a thing that happens that all these mast cells all of a sudden get excited and release all their granules. It can become a kind of forward-feeding circle, too, where mast cells degranulate, which cause other mast cells to degranulate.

It's almost like those dominoes going forward, and that's something called mast cell activation syndrome. So mast cell activation can be a noncancerous condition or benign condition. I don't wanna call it benign because it's serious for some people who have it, but a non-clonal process or not a cancer, but have all the kind of manifestations that we do see in systemic mastocytosis, the clonal process, the chronic blood cancer.

And so on that range of disease, there are some patients who have disease that isn't very aggressive in terms of the numbers of mast cells and the way it grows over time, and we call that indolent. And then there are a set of patients who have systemic mastocytosis where there are so many mast cells and they're starting to get end-organ complications, or the number of mast cells are really increasing, and it's turning into a mast cell leukemia, in fact.

And so that's the separate two bins of patients that we see with systemic mastocytosis.

Pathak: Okay, that's really helpful, and I think a really helpful description of what's happening inside the body. So for, you know, most of us, when we think of our mast cells, those are the cells that cause some of the allergic reactions that we might recognize very commonly. But I'd love it if you can—you really did a great job showing us and helping us imagine what's inside our body and what's happening. Can you help us understand what a typical patient's experience in life is like with this type of condition? Particularly, let's start with the indolent form

Gerds: Yeah, for the indolent form, and I would say for the aggressive form as well, it really depends on where the mast cells are. One of the most common presenting symptoms is cutaneous mastocytosis, or mast cells in the skin. And you can see these kind of small red spots, if you will, on the skin. They're typically not raised.

They can be itchy. They kind of appear and then regress over the course of a few days. That makes it really hard to get a snippet of these if you want to try to biopsy cutaneous mastocytosis, 'cause they'll appear, and then by the time you get ready, get a patient in, get a biopsy, they're gone. So that can be one of the symptoms that a patient experiences in the skin.

Some patients can even, in the skin, have this thing called Darier's sign. You press on the skin, and you can get these reactions in the skin. Again, the idea is if you kind of smush the skin, all these mast cells then reactivate. Really, probably what I see, at least in my clinic, the most is GI involvement or involvement of the gut.

Pathak: Hmm ...

Gerds: Or chronic nausea even sometimes that goes unexplained. The typical story there is a patient with chronic diarrhea. You know, they've tried antacids, they've tried antibiotics, they've gone to the gastroenterologist, who says, "I don't know what to do. Let's do a colonoscopy." And they look in there with a colonoscopy, take some biopsies of some areas that look a little red, and we see the mast cells in there. And they're abnormal-looking mast cells, too. They're spindle-shaped. They have different proteins on their surface you may not normally see on a mast cell, and they might actually be able to get enough of those cells to do the mutation testing for KIT D816V, which is the main mutation that causes this disease in those cells.

So GI involvement can happen. It can lead to osteoporosis and osteopenia. It can lead to, in rarer cases, cardiac involvement, and so patients can have cardiac symptoms like heart failure. And it can lead to the spleen getting bigger, an organ that's on the left side of your abdomen that's kind of like a gigantic, overgrown lymph node that helps filter the blood, or liver involvement as well, where the liver can get big and cause problems.

So it really depends on where those mast cells are collecting that relate to the symptoms.

Pathak: That's really interesting. So it's almost like each patient who may have this condition is like a snowflake, experiencing very individual, unique-type symptoms.

Gerds: Yeah.

Pathak: So help us understand then, does this shift over time for an individual patient?

So if I... depending on where the mast cells are in me as an individual, could I have these differing symptoms over the course of my journey, or is it more like your predominant experience is based on where the mast cells are, and that's not gonna shift over time for you?

Gerds: Yeah. For most patients, wherever they have the mast cells at the time of diagnosis is where the mast cells are for the duration of their disease.

Mm. So if a person has predominantly GI symptoms because of the mast cell involvement there, we're likely battling with those GI symptoms for the duration of their care. Other areas can pop up, so that's why we do monitor for things like increasing spleen size or liver size, osteoporosis and osteopenia, and doing that kind of careful work there to make sure other things don't pop up as we're focused on this one organ system or two organ systems that's affecting that patient.

The truth of the matter is, though, the treatments that we have really try to address, in large part, the whole body. So it's very fortunate that we do have agents now that are systemic and can treat disease in different places, which I think is really important and can positively affect the course for patients.

Pathak: Hmm. And can you help us understand how common it is? Is there a difference between genders? Is there an age predominance?

Gerds: Yeah, there's two different flavors, if I will. You know, in children, we do see mastocytosis. It's typically cutaneous mastocytosis, so just limited to the skin. And it's often self-limited. You know, this mastocytosis can regress over time and very rarely turns into systemic mastocytosis, the whole-body form.

Mm. Systemic mastocytosis is generally diagnosed in adults. It's, again, a pretty rare disease. Mastocytosis in all of its forms has a prevalence of around one in 10,000 people, which is pretty, pretty rare. And most adults who are diagnosed are in their 50s to 60s.

It's pretty uncommon in younger folks. But as people age, we do see it more often.

Pathak: And it sounds like, from the way you've described it, because it can show up in different ways for different people, that there may be a common pathway of misdiagnosis that a lot of people experience. Can you talk a little bit about other things that people might have been diagnosed with or the pathways they may have gone down before they finally are able to be diagnosed?

Gerds: That's really important that we talk about this because it's really the intersection of a disease that has many presentations and many potential symptoms, and the kind of old adage, "If you hear hoofbeats, think horses, not zebras," 'cause this is certainly a zebra.

And so, again, I rely on GI symptoms, the gastrointestinal symptoms, because they're so common, but it also illustrates a good point. A patient will say, "Man, I got this chronic diarrhea. I'm going all the time. It's very impactful on my quality of life and potentially my nutrition and all these other things."

And they'll get this workup. Well, maybe this is IBS, and they get treatment for IBS. Well, maybe it's some other thing. Maybe it's a chronic infection. Let's try some antibiotics.

And a patient may go two, three, four, five years before they get that diagnosis, which can be really challenging. And a lot of testing can be done that may not get you there. You may find a lot of red herrings, meaning that, well, we think it might be this, and then you do a test like an MRI or a CT of the abdomen, and you might find some other thing that may not be the cause, but you kind of chase it down, if you will, and it can be a distractor and lengthen that time horizon to be diagnosed.

So it is a challenge. I would say the vast majority of patients I see in my clinic have had alternative explanations for this proposed to them by doctors trying to get to the bottom of things year after year, month after month. And then ultimately we find the mast cells, we do the mutation testing, and okay, this is clearly what it is.

Now we can kind of put it together.

Pathak: Yeah, no, absolutely. And thinking about this as a primary care doctor, imagining we always want to be thinking sometimes about zebras, but you're right, we are very much focused on the more common things being common. And that's usually generally the path we'll go down.

So walk us through what you were just talking about. So if someone finally gets to your office, step by step, help us understand what are the things that you're going to do to make the definitive diagnosis and to help you understand what the treatment and management pathway needs to be for each individual patient.

Gerds: It's a great question. I think there are three critical pieces of information that kind of get you on the right path that you need to find. One are the mast cells themselves. You really want to get that biopsy from an involved organ and look at it and see those spindled mast cells that have abnormal expression of protein on their surface, that are kind of clustered together.

That's a key piece, is finding those mast cells. It's really impossible to make the diagnosis without that. Mm. So if it means colonoscopies to try to find them or upper endoscopies, if it means skin biopsies, if it... Some patients, we do bone marrow biopsies because there can be mast cells, clusters of mast cells hiding in the bone marrow, too.

So getting that primary proof that those mast cells are there and they're abnormal. The second piece of information is finding the mutation inside those cells. And that is that KIT mutation I mentioned before. The vast majority of systemic mastocytosis, we will find that KIT mutation. And it's important for a couple of reasons.

One, it helps confirm the diagnosis, which is very important. Two, it's important in treatment. The advent of KIT inhibitors have revolutionized the care of not only aggressive systemic mastocytosis, but indolent mastocytosis as well. And it's really important to find that KIT mutation because, if the KIT mutation is present, then that means that these KIT inhibitors can work.

If there truly is no KIT mutation, we think about other drugs like imatinib that might help patients that don't really work at all when that KIT mutation is present. The third thing that is important in the part of the workup is a blood test called tryptase, and tryptase can be a clue to making the diagnosis, and it's one of our diagnostic criteria, admittedly.

But it's kind of this weird thing, 'cause there are inherited syndromes that can just lead to natural elevations in tryptase, such as hereditary alpha-tryptasemia. Allergic reactions can make tryptase levels go up, so you gotta be mindful of that, too, when interpreting those results. And in some patients with true indolent systemic mastocytosis, they may not have a very elevated tryptase level.

We could have patients with lots of symptoms, we see the mast cells, we find the mutation, but they have a tryptase level of eight, which is very unimpressive. Mm-hmm. Mm-hmm. So it is a tricky thing, but kind of a key piece of putting it all together. And sometimes we monitor these tryptase levels. Certainly in patients who have high tryptase levels, we'll monitor that as their therapy goes along.

So that's the core of what we are looking for to make the diagnosis. And then the next layer in the, kinda, the jawbreaker of diagnosis, understanding this disease in an individual, if you will, is looking for end-organ dysfunction. So we wanna know, is the spleen big? Is the liver big? We may do imaging for that, either ultrasound or CAT scans.

We wanna know the bone density. Do they have osteopenia or osteoporosis as a result of the disease? We often get echocardiograms to make sure there's good cardiac function. And in patients who have GI symptoms and have not had a recent endoscopy test, we would recommend a colonoscopy or upper endoscopy to put that together, as well as a bone survey, which is like a series of X-rays looking at all the bones to make sure there's no lytic lesions, to make sure there's, again, no end-organ involvement.

'Cause end-organ involvement changes our outlook on indolent systemic mastocytosis and tells us it might be a little bit more aggressive, and we need to alter our treatment plan based on those results.

Pathak: Health Discovered will be right back.

Pathak: Dr Gerds, before the break, you were walking us through how end-organ involvement can be a defining clue in diagnosis, and I'd love to stay there for a minute because you've also touched on the fact that not all systemic mastocytosis is the same. So let's talk about what makes the indolent form distinct and what differences mean for a patient's prognosis when it comes to their treatment and their quality of life.

Gerds: Yeah, I think that's a good key question to ask because, in general, indolent systemic mastocytosis, those patients, even without aggressive KIT inhibitors, if we can just even manage the symptoms with more conservative measures, can live a very long time with this disease, and diseases that are measured in, you know, even decades rather than years.

Where aggressive mastocytosis are these diseases where, you know, without disease modification, these diseases, they can be quite aggressive and take people's lives within, say, five years even, or a shorter period of time, depending on how aggressive it is. And so that's a clear dichotomy there, where we're saying, yeah, a patient can live decades versus a few years.

I mean, that's a big spread. Obviously, there are patients in between, but those are the kind of general categories we think about in terms of this disease.

Pathak: And does indolent progress to aggressive, or are you on these different pathways from the get-go?

Gerds: Yeah, I think patients can. Most patients with indolent disease, their disease will remain indolent for a very long time.

But there is a subset of patients where it... you can almost imagine it like you're catching the aggressive systemic mastocytosis early, right? Mm-hmm. And it looks indolent, and it has a kind of a rapid disease course. Now, this is a changing thing, 'cause again, the advent of KIT inhibitors have really started changing the landscape of the amount of progression we observe in our everyday practice, which is a very good thing, of course.

Pathak: Right. Yeah, no, that's really helpful because what we often think about in primary care practice is the earlier we can intervene on something for certain conditions, the better. Mm-hmm. So we can prevent it from moving to something that's more advanced or potentially more aggressive. Is that how you think about indolent mastocytosis, or is this really more of a watch-and-wait approach?

Gerds: Yeah, I think for patients who don't have symptoms, say they were getting their regular cancer screening colonoscopy, and we happen to stumble upon it, which happens, and they're absolutely, utterly asymptomatic, their tryptase is not super high, you know, that is the subset of the patients where we can just keep an eye on things.

That disease is very unlikely to all of a sudden fall off a cliff, if you will. Now, there are patients who are symptomatic. Obviously, you want to make them feel better, and it turns out the therapies we use to treat their symptoms to make them feel better are the same treatments we give to aggressive disease.

And by doing so, there is really good data coming out now that show that in indolent systemic mastocytosis, by using these interventions earlier, when patients become symptomatic rather than when they progress to aggressive disease, so if they're symptomatic indolent, treating them with the drugs can actually lead to better long-term outcomes.

We'll see clones shrink. We'll see progression delayed and all these really important endpoints for those patients with indolent disease.

Pathak: You know, and as you're talking, I'm really reflecting on how we opened our conversation, which was that the standard of care is clinical trials. Mm-hmm. Because there's so much, given that this is a rare disease and that there are these rare pathways and subtypes, you're really constantly needing to have these trials to see what are the best options.

Am I seeing that correctly?

Gerds: Yeah, absolutely. There's a lot of stuff that's on the horizon. There are newer, better KIT inhibitors that are in development that have worked in patients who have had prior KIT inhibitor treatment. There are other drugs such as BET inhibitors that are being developed in mastocytosis and mast cell disorders, as well as several others in even earlier phase development, preclinical and early human studies.

And so, you know, the field is growing. For such a rare disease, it is quite remarkable that the field is sponsoring and is putting forth this research to make patients' lives better. It's not the same kind of cost proposition, again, as... I don't want to pick on hypertension, but you think about if you get a drug approved for hypertension, like the value a company could have in that.

So I really applaud entities, both federally funded and privately funded entities, that are dedicated to diseases like this to make patients' lives better, because the math may not always work out in that way.

Pathak: Hmm. Yeah. That's really powerfully said. So, for someone that's listening today, and for a primary care provider like myself, how would you help a patient or someone who suspects that they might have some of these symptoms, but they may be feeling dismissed, overwhelmed, or—yeah, they may feel like their provider's not going down a path that will get them to you soon enough? Can you share some practical next steps so that we can move that process along a little faster?

Gerds: Oh, great question, and we don't want anyone kind of, you know, languishing in the purgatory of a non-diagnosis for this, right?

And so I think, you know, a primary care doc who says, "You know what? This is a weird constellation of symptoms. We don't have really an obvious answer." You know, something simple that's easy to do that's kind of cost-effective is just checking a tryptase level. Now, it doesn't mean if the tryptase level is normal, they don't have systemic mastocytosis.

But if it's high, it kind of gets you thinking about that. Or at least if the tryptase is high, it gets you thinking, "Maybe I should refer them to an allergist to take a look at this." An allergist and immunologist are close partners in mast cell disorders. Like, typically, if you think about the field of mastocytosis and mast cell disorders, anything that's not clonal up until it becomes a cancerous clone is handled typically by allergists and immunologists.

And then once it becomes a cancerous clone, it's handled by, you know, blood cancer doctors and hematologists like myself. So getting a tryptase level on someone who has kind of vague, inflammatory, autoimmune-type symptoms that you're just not clear on could be a clue that triggers your mind. Like, "Whoa, tryptase is elevated.

Maybe it's a mast cell disorder. I should send them to a hematologist to rule out systemic mastocytosis or an allergist to think about, like, well, why is the tryptase elevated in this patient?"

Pathak: Yeah, you know, that's really helpful. Just thinking through this as a primary care doctor, I can certainly see someone who comes in with these very strange sort of allergic-type symptoms—mm-hmm—that seems like a very, um, reasonable and helpful pathway to follow from that standpoint. I'm also hung up on the GI symptoms, though, because when you see a sudden change in your bowel movements, that deserves follow-up.

Gerds: Yeah.

Pathak: You don't want to necessarily just sit on that for very long, where you're just sort of like, "Oh, well, let me just keep trying things at home or not move forward on a diagnostic pathway."

So am I thinking about that right?

Gerds: Yeah, absolutely. I think in those patients where, again, I have the benefit of seeing them on the back end, they'll have these symptoms, and they get that colonoscopy. That's really the thing that gets them there. 'Cause you'll see, if a patient's got a lot of mast cell burden in their colon, a gastroenterologist will see it.

It'll be these kind of red plaques or papules or areas in the colon, and they'll take biopsies. Sometimes they don't have the red plaques, and it's just on random biopsies. So I would also argue if you have a patient you're going to send for a colonoscopy who you're maybe thinking about this, make sure they at least take some random biopsies if they don't see anything.

'Cause I've had a few patients have their disease identified in that manner, too. And ultimately, at least I can speak for our practice here, you know, we're always happy to see patients to rule out systemic mastocytosis, right? So if, "You know, this is weird. It kind of sounds like this." We get referrals for that all the time.

"Hey, I'm thinking this might be systemic mastocytosis. Can you rule it out?" And then we can take the baton from there, do the appropriate workup, get all the tests ordered, and say, "Yep, this is," or, "Nope, this isn't. Let's kind of go back to the drawing board on things."

Pathak: I imagine for a lot of patients, particularly if there's some allergic component, skin or allergies or even GI, that people will be trying a lot of over-the-counter remedies.

Mm-hmm. Is there some sort of signal where you try these and they don't really help, or you may be trying these and just need to take them for such a long period of time that would trigger a reason to talk to your healthcare professional about these symptoms?

Gerds: Yeah, that's a good question. You know, I've seen some patients, you know, using various creams and, you know, steroid creams and other topicals for their systemic mastocytosis, and they're just like, "Yeah, every time I get these spots, I put the cream on them, and they just disappear."

And it's like, well, they're probably gonna disappear anyways. But the fact that they kind of keep coming back, you know, that should really prompt a workup. You know, again, with the GI symptoms, again, 'cause it's another common presentation, you know, lots of patients will try, like, antidiarrheals, and that'll work.

Right? Like, right? I definitely, in some patients who are more indolent, you know, sometimes I just do a little bit of antidiarrheals and some antihistamines, and things get... You know, their symptoms are well controlled, and we may not have to start a KIT inhibitor right away. You know, that's a possibility.

But a lot of times, those conservative measures, if the disease is truly requiring, say, more advanced care, like a KIT inhibitor, it's gonna burn through those things.

Pathak: Mm.

Gerds: If the indolent systemic mastocytosis is so mild that those things make it better, then I'm not sure you're gonna be worse for wear by not making that diagnosis a little bit earlier and getting that under care because, again, very indolent disease, like disease that's easily controlled with very conservative measures, we may not necessarily need to start a KIT inhibitor right away.

But I do think there's a benefit to that by getting plugged in with a hematologist, right, who can care for you in the long run. I think that's it. It's stuff that just doesn't get better, right? Stuff that kind of just lingers on. You know, oh, maybe it's a little bit better with my antihistamines, or maybe it's a little bit better with my Imodium, but we're not quite getting rid of it. Then I think that's a good red flag to go a little deeper.

Pathak: That's great. I think that's such an important piece of information, so thank you for saying that. Because often we'll have patients who are taking this and managing on their own, but we really want to know—mm-hmm—when you're on something like this long term because we need to understand why.

Gerds: Exactly.

Pathak: And I'm hoping that for anyone who's listening who might feel like they're having some of these very strange allergic symptoms, sudden changes in their bowel movements that have been persistent, that they really lean into talking to their healthcare provider and bringing some of the messages you've shared with us to them.

Any final thoughts for someone listening?

Gerds: Yeah. I think the challenge is sticking with it, so I'd encourage folks to keep working at things, trying to get to the bottom of it. It may be systemic mastocytosis, it may not. But, you know, keep trying to get to the bottom of things. And it's sometimes a long journey, an arduous journey, but I've definitely seen that in patients.

And once we figure out the diagnosis, and we get them on the treatment, they feel better, and their lives can be better. We do have treatments for these things. We just gotta kind of figure it out, if you will, right? And so keep plugging along, I guess. I like the advice you gave, too, of speaking up. I think that's incredibly important as well.

Let everybody know what you're feeling and how you're feeling. Try not to dismiss too much, and, you know, try to get to that answer if you can.

Pathak: Well, I want to thank you so much for your time.

Gerds: Well, thank you so much for having me. It's been a pleasure.

Pathak: A special thank you to Candice Pauley for sharing her diagnosis journey.

To hear more about her, check out her show, Mastcast: An SM Podcast. And thanks again to Dr Aaron Gerds for shedding more light on indolent systemic mastocytosis. To find out more about Dr Aaron Gerds and indolent systemic mastocytosis, make sure to check out our show notes. Here's what I'm taking away from the conversation.

Pathak: ISM is a chronic blood disorder where abnormal mast cells accumulate in organs throughout the body, and because its symptoms can mimic so many other conditions, patients spend years searching for answers before getting a diagnosis. If you or someone you know has persistent unexplained symptoms, especially GI issues, skin reactions, or vague allergic-type symptoms that just don't resolve, don't dismiss them.

A simple tryptase blood test can be an important first clue, and a referral to a hematologist or allergist can open the right doors. As a primary care doc, that is really important for me to understand. I'm certainly gonna spend some time thinking about ISM as a possible diagnosis, and I probably will be ordering more tryptase blood tests.

And while ISM is a serious condition, the indolent form is manageable, and we've got new targeted therapies that have changed the landscape, so there's real reason for hope. Thank you for listening. Please take a moment to follow, rate, and review this podcast on your favorite listening platform. If you'd like to send me an email about topics you're interested in or questions for future guests, please send me a note at [email protected].

This is Dr Neha Pathak for the WebMD Health Discovered Podcast.