Does anyone really want to hear about someone else's illness? Having been sick for two years now, I can actually time to the second concerned platitudes about my health transform to the glassy-eyed, ‘Oh God when will this end’ expression and it's usually at about this point…'I have a rare condition called Idio-’

And there it is. The dazed nodding when I can tell nothing is going in and that they very much want the conversation to move along. Quite simply if you have a rare disease – defined as an illness that affects 1 in 2000 – you’re going to struggle to get people to engage because it has likely not ever touched them or their lives, there’s no common ground to share the experience. It’s no one’s fault, even my GP had to get me to spell my illness down the phone so he could Google it during our first consultation.

But tomorrow is World Rare Disease Day and since I refuse to ‘show my stripes for rare diseases’ (wearing stripes is the traditional awareness raising strategy) or wear a funny T-shirt that says, ‘Auto-immune disease: Because the only thing tough enough to kick my ass is myself’, I’m writing this.

I've written a lot over the last few years about the consequences of chronic illness. I’ve detailed how insensitive people can be and how knowing I might have a limited lifespan spurred me on to embrace new, if not always wise, adventures, (yes, I’m referring to the narrowboat we moved the whole family onto in winter).

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However, you might have noticed that I often refer to my illness as ‘two auto-immune conditions’. The first remains undiagnosed but is treated fairly successfully by a low dose chemotherapy called Methotextate. Though I’ll be on that highly toxic medication for the rest of my life and I lose one day a week feeling like I’ve a hangover sent from Satan, I’m luckier than around 95% of those with rare diseases for whom research shows there is no effective treatment.

The other condition I have is…stay with me here, don't let your eyes glaze over, this could one day be important to you…Idiopathic Subglottic Stenosis. It's a chronic disease, which means it’s incurable. It’s also vanishingly rare with only around two people in a million being diagnosed, most of whom are women.

It can also be caused by intubation during surgery or breathing in chemicals but for me it appears to be a symptom of my autoimmune condition, my body is effectively constantly attacking itself, over zealously responding to phantom illnesses which in turn actually does make me sick.

One of the symptoms of this is that I grow scar tissue in my trachea. Yes, it is terrifying and can be life threatening. Imagine being slowly, and in some cases very quickly, strangled by an invisible force until you whistle when you breathe in, until you're so exhausted you cannot tie your shoes, until you’re weeks if not days away from a fatality as I was when I was finally diagnosed and admitted for emergency surgery.

When I initially went to the doctor, he told me, as so many women are told who are out of breath, that it was baby weight and asthma. But inhalers do not help this condition.

The Herald: Don't be fobbed off by doctors, says Kerry HudsonDon't be fobbed off by doctors, says Kerry Hudson (Image: free)

In fact, Idiopathic Subglottic Stenosis is also not caused by allergies, weight, diet, reflux or a lack of exercise, as women are often gaslit into believing. After my initial doctor’s visit, it took me around another three months to be diagnosed properly and the only reason that I was was because I could tell that I was dying, I had a little boy and I was desperate to be there for him. In Prague, I was given a surgery which temporarily opened my airway again. I had another surgery the following year in Glasgow because, like death and taxes, for me the third thing that’s inevitable is that the phantom strangler will return. Some women have ‘dilation’ surgery every few weeks, some women like me, the lucky ones, seem to be able to go a few years between surgeries.

Every time I write about this condition, someone contacts me to say that this sounds like their sister, their friend, their mum or themselves. So this feels like a good time to remind you, if you're reading this and you suddenly or progressively struggle with breathing as an adult with no prior history of breathing difficulties go to your doctor.

If you have stridor, if you're wheezing or whistling when you breathe or sound, as I did, like Darth Vader's younger prettier sister, if there is no sudden attack, as with asthma, but instead, you're short of breath when you exert yourself or you’re anxious, go to a doctor.

Go to your doctor and don’t allow them to tell you it is simply asthma or weight or diet as so many women have been told before. Ask them to refer you to an Ear, Nose and Throat specialist and insist that that specialist inspects below your vocal cords for scar tissue. It might not be Subglottic Stenosis, I hope it isn’t, but it could be and if it is it can be treated.

I almost left my little boy without a mum which is unimaginable to me. So, I would like as many people as possible to know about this illness and yes, it is enormously frustrating when people's eyes glaze over when I start to tell them about my condition.

Still, I'll keep talking about it. As someone who literally can't afford to waste their breath I choose to use mine on raising awareness of this rare disease that makes me one in half a million, kid.