Our journal article about how XLH is a whole-body, whole-life, whole-family condition was, on the surface, specific to XLH, since that’s within the authors’ primary expertise, but I believe that just about everything we wrote (except for the details of genetic transmission) is equally applicable to the other chronic hypophosphatemias.
Sure, there are some differences. Tumor-induced osteomalacia (TIO) could be said to not be whole-life, since it often presents in adult hood, so many patients don’t experience the symptoms in childhood. But it’s still an important reminder, that TIO can happen at any age, since clinicians may falsely assume it’s purely an adult disorder (the opposite of the false assumption that XLH is purely a pediatric disorder).
Some of the chronic hypophosphatemias (not XLH or TIO) carry with them a risk of infant mortality, but some of those patients do survive into adulthood, so even there, it shouldn’t be assumed that no adults have the condition.
There’s a new journal article out that establishes that two of the chronic hypophosphatemias, ENPP1 deficiency and ABCC6 deficiency present, overall, a very similar picture to XLH, even if it’s a different gene causing the issues, and a different pathway (not involving the FGF23 that causes XLH’s phosphate wasting). You can even see a hint of our whole-body/life/family language in the title: “Lifelong impact of ENPP1 Deficiency and the early onset form of ABCC6 Deficiency from patient or caregiver perspective.”
Beyond all the really good information in the article, what struck me the most was the engagement of patient advocates (parents of patients, not scientists) in the writing of the article. Two of the named authors are leaders of GACI Global, the relevant patient group, and the article mentions how the scientists engaged with that group during the early stages of the research. It’s so, so, so important to engage knowledgeable patients when creating surveys and interview questions about the patient experience. It helps with the “you don’t know what you don’t know” problem, when scientists don’t know the limits of their understanding of a rare disorder compared to what patients know, so they don’t know the right questions to ask and don’t know when they’re making false assumptions about the disorder.
Final reminder: If you live in England, Wales, Scotland, or Ireland and have XLH (not one of the other hypophosphatemias in this case) or your child has XLH, please take a few minutes to fill out this survey which closes this weekend, I believe. If you’ve already done it, and you know someone who qualifies who hasn’t done it, please pass the link along, or share it on your social media. Getting a lot of responses is absolutely critical to the future of access to state of the art treatment for XLH patients (and potentially for the other hypophosphatemias, since if XLHers are denied access, then most likely so will patients with the ultra-rare versions).
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Please note that the author is a well-read patient, not a doctor, and is not offering medical or legal advice.
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