Explaining Rare Disease: How to Talk About Indolent Systemic Mastocytosis

Navigating the social dynamics of any chronic illness can be a challenge. So it probably doesn’t come as a surprise that trying to explain a rare disease—one that presents with a complex, highly variable set of symptoms—is no easy task. You’ll learn quickly that most people have never heard of a mast cell, and many tend to be skeptical of medical conditions they don’t understand.

While explaining my condition will probably never be completely seamless, living with indolent systemic mastocytosis (ISM) has taught me a lot about navigating the social aspects of chronic illness and disability.

How I talk to other people about ISM

I’ve been workshopping my elevator pitch about what ISM is ever since I was diagnosed. After trying out countless approaches, I’ve realized that the most important thing to focus on is whatever keeps me safe and makes spaces accessible. From there, I can share extra details based on what that person is open to learning.

My baseline, everyday explanation for ISM usually goes something like this:

"I have too many of an immune system cell called a mast cell. My mast cells also don’t behave properly, so my body interprets normal, everyday things as attacking me, and when my body goes on the defensive it causes me to have allergic reactions."

Being understood is more important than being technical

I choose my words based on who I’m talking to and what I need to accomplish. What I say to hotel staff when requesting accessibility accommodations is wildly different from how I’d explain things to a new friend, a colleague, or a doctor who isn’t familiar with ISM.

When you’re talking to healthcare providers the difference between allergies and sensitivities is relevant. But in casual conversation, those terms are often used interchangeably. The ultimate goal in social settings is to be understood, not to help someone pass a medical school exam. Use whichever terms communicate your safety needs most effectively to your audience.

Being "allergic to people" makes life a bit complicated

In simple terms, ISM has made me sensitive to all fragrance products. That effectively makes me allergic to other people and the scented items most of us use every day.

While fragrance sensitivities aren’t uncommon among folks with mast cell diseases, mine are on the severe side. They developed gradually a few years after my diagnosis in 2009. I began noticing that strong perfumes and body sprays made me feel sick in various ways, and over time, that reaction expanded to almost all artificial scents.

As an extroverted person, I’m pretty sure there’s no other sensitivity that could feel more inconvenient than being allergic to people around me.

Managing these sensitivities socially has been one of the trickiest parts of living with ISM. Medical guidance for systemic mastocytosis emphasizes avoiding your triggers, but avoiding fragrances entirely is nearly impossible. Scented products are everywhere. I can’t use a public bathroom, see a movie, or even sit outside my partner's kids soccer practice without encountering fragrances or someone wearing them. I can’t even get some of my medical providers to stop wearing fragrances.

Scent sensitivities as a built-in litmus test

For a long time, I let people make me feel like my fragrance sensitivities were a burden and inconvenience to accommodate. I felt guilty for bothering others with my medical needs—until a friend hosted a potluck.

Without calling me out, she included a gentle note on the invite asking everyone to come fragrance-free so the space would be safe for a guest. That was a turning point for me; I realized how straightforward and simple it can be to make a space accessible when people care.

That realization helped me stop making myself smaller. I live in a body that functions differently than most, and instead of letting people make me feel like I don't belong, I’ve started working to create inclusive spaces for others.

Existing outside society's norms as a chronically ill person comes with an unexpected silver lining: it serves as a built-in litmus test for who is worth your time and energy. I would never choose to have these sensitivities, but the people who make an effort to accommodate me have turned out to be the kindest, most empathetic people in my life. If anyone makes you feel like a burden for existing in a body that is different, take that as the red flag it is. You deserve better.