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I was diagnosed with indolent systemic mastocytosis (ISM) in July 2022, but long before that, I’d gotten used to dealing with a bunch of diagnoses and strange symptoms, including chronic bone pain.
A decade prior, I’d been diagnosed with cutaneous mastocytosis (CM)—a buildup of immune system cells called mast cells that manifested as a rash. I took antihistamines to manage it and kept on living life.
But other things kept coming up. About once a year, I’d have an episode of vomiting and abdominal pain that was so bad, I’d have to go to the emergency room. I was always told it was food poisoning. Over the years, I had also been diagnosed with an irregular heartbeat, irritable bowel syndrome (IBS), and osteoporosis. I also had continued debilitating bone pain after breaking my hip and femur when I took a nasty fall in my garage.
For years, doctors seemed confused about what was going on with me, but nothing seemed to help. Then, I got a call from my primary care doctor that an ISM researcher in Washington, D.C., had seen some of my health markers in the hospital system and was pretty sure he had the answer.
The Relief and Fear of Getting a Diagnosis
I drove nine hours from my house in Georgia to a center of excellence hospital to see the specialist, who confirmed that I had ISM—I ticked every diagnostic box. Virtually all the issues I had over the years could be traced back to ISM.
My diagnosis made my jaw drop. I felt so relieved, like the puzzle had finally been put together and there was a chance that I could get my life back.
But there was a heavy dose of anger and fear, too. I was mad that my doctors had missed the underlying cause of my symptoms, even when most CM cases in adults turn into ISM. I was also really scared—I consulted Dr. Google (bad idea) and went full panic mode when it said I could be dead in three years. Fears of missing out on my kids’ (or future grandkids’) lives flashed in my mind.
With ISM, you can have life-threatening anaphylaxis (allergic reactions) due to the high numbers of mast cells in your body. I have reactions to insect bites and fragrances (among other things), so my doctor gave me an EpiPen to use if I ever started experiencing anaphylaxis. That meant I had to make my house totally fragrance-free and change a lot of my day-to-day habits.
At first, everyone in my house was hypervigilant. My husband and son wouldn’t leave me alone just in case something happened, and I was afraid to go anywhere. It kind of made me feel like a child. Plus, I didn’t know if I’d be able to continue gardening, my favorite hobby.
ISM Education and Community Support Made My Condition More Manageable
Over time, things got better. I was able to identify the things that triggered me most. And in 2022, I joined a support group with The Mast Cell Disease Society. When the leader of that group stepped down, I decided to jump into the leadership role. I’ve learned so much from the other people with systemic mastocytosis in my group. They even helped me identify other symptoms I had that I didn’t even realize were related to my ISM diagnosis, like constantly needing to clear my throat or blow my nose.
I’ve also learned more about ISM by doing research online. I lean on my daughter and her fiancé, who are both molecular biologists (lucky me!). They help answer any questions I come across while I’m reading more about ISM.
My family’s support plus my systemic mastocytosis group have made me feel so much more confident. I’m much more equipped to advocate for myself with doctors and to share my own story with others. I've even had doctors tell me I know more about ISM than they do!
Basically, I’m not fearful anymore—I’ve moved from paranoia to paying close attention. I’m familiar with my triggers and how to avoid them. Plus, my family encourages me to rest when I need to so I can keep doing fun things with them when we’re traveling or gardening. I feel much more stable.
A big part of that also comes from my treatment plan. My doctor started me on first-line antihistamines, but immunotherapy shots (allergy shots) worked better for me. I’ve been taking those once a month since 2022 to lower my sensitivity to triggers, which reduces my risk of getting anaphylaxis.
In 2024, I started treatment with a tyrosine kinase inhibitor (TKI) drug called Ayvakit (avapritinib). The drug works by targeting the misfiring gene that tells my body to make too many mast cells. A few of my friends took it with good results, so I decided to give it a try. Things aren’t perfect, but it’s certainly helping. I haven’t had any severe reactions where I’ve needed to go to the hospital in a really long time.
Staying Confident Despite My ISM Challenges
Even though I’m in a much better spot, managing ISM will always be hard. Since I’m triggered by fragrances, I have to have my own office at work, and I usually wear a mask when I talk to people. Asking people to cut out all fragrances is hard, I get it. But it means I have to walk the long way around the office to avoid certain coworkers’ desks and that I can’t use the employee bathroom since it has an air freshener in it. Work can sometimes feel very isolating.
Being triggered by smells can also make it hard to visit people or be in spaces that are new to me. During a trip to visit family in Florida this past spring, I started having a reaction to the plug-in air fresheners in my relative’s house. We had to just roll with the punches and for the rest of the trip, we met at restaurants or open-air spots instead.
It’s not easy. But it just makes me want to get the word out even more about our ISM community so that doctors and everyday people can better understand what we’re going through. I’ve definitely turned a few skeptical coworkers into believers at this point.
Connecting with others who have ISM is also so helpful. I continue to lead my support group, and I moderate a few Facebook groups where people with ISM can learn from each other. I also have an Instagram page where I share more information about my experience with ISM—I’ve found it to be really cathartic. There are tens of thousands of us with this rare disease, and improvements in diagnosis and treatment give me a lot of hope for the future.
As told to Julia Landwehr


