Just how rare is atypical hemolytic uremic syndrome?

What constitutes a rare disease? In the U.S., the Orphan Drug Act defines a rare disease as any disease affecting fewer then 200,000 people. The National Organization for Rare Diseases (NORD) reports that over 10,000 rare diseases exist. That’s way more than I would’ve imagined.

Let’s compare a few numbers. Lupus occurs at a rate of roughly 1 in 2,000 people. Cystic fibrosis occurs at a rate of around 1 in 3,200 Caucasian births and 1 in 15,000 Black births, while it’s somewhat less common in other ethnic groups. Some form of Ehlers-Danlos syndrome occurs at a rate of around 1 in every 5,000 people.

But how often does my rare disease, atypical hemolytic uremic syndrome (aHUS), occur? The aHUS Alliance reports a rate of 1-2 cases in 1 million people.

That puts aHUS in the ultrarare category, which can make it hard for patients and even medical professionals to find information and support. Finding up-to-date information about rare diseases can be a matter of life and death. I’ve had doctors who’d never heard of aHUS. And it’s not their fault; aHUS is really that rare.

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I was diagnosed with aHUS in 2020 after I nearly died of multiorgan failure. I remember sitting in my hospital bed feeling so overwhelmed and confused. After a quick trip to Google to learn some basics about the disease, I next surfed social media. I had the most luck with two support groups I found on Facebook: Adults Living With Atypical HUS and Atypical HUS Families.

Those two pages not only offered a wealth of information about the disease, but they also made me feel less alone. There I found other people who knew exactly what kind of terrifying medical journey I was going through. In over a month in the hospital, exploring those Facebook pages were the first times I didn’t feel alone.

In the hospital, there was so much to take in. All of this new information and damage to my body was just thrown at me during supershort, hazy updates from doctors, occurring when they’d wake me from a drug-induced dead sleep at 5 a.m. Being told crucial information while half-asleep was already hard to handle, but being told all kinds of new and long medical titles was harder. That’s where social media helped me a lot.

As the years have gone on, those pages have exploded with information and resources, and they’ve attracted newcomers who’ve been recently diagnosed. I’ve also found information on other sites, including those of NORD, Alexion Pharmaceuticals (which manufactures my medication, Soliris, the brand name for eculizumab), the National Kidney Foundation, and aHUS News, to name a few.

Live, in-person events hosted by the aHUS Alliance, the National Kidney Foundation, and the United States Thrombotic Microangiopathy Alliance have also been helpful. These events bring together patients with similar issues and put them face to face with experts in the rare disease world. That gives patients the rare opportunity to ask questions, get information, and network.

Those few in-person, social media, and other internet resources have been invaluable during my aHUS journey. They were game-changers in helping me connect with others who’ve been through the same difficulties, and they’ve even given me new treatment options to pursue.

Being rare is not where my story ends. It’s just the beginning.

Note: aHUS News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website. The opinions expressed in this column are not those of aHUS News or its parent company, Bionews, and are intended to spark discussion about issues pertaining to aHUS.