The sooner you treat XLH, the sooner you can start managing your symptoms
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For adults with XLH, early diagnosis and treatment is important to help manage symptoms.
XLH is a rare, lifelong, genetic disease that can get worse over time when left untreated.
XLH affects up to 1 in 20,000 people and can impact the bones and muscles of both children and adults.
People with XLH don’t have enough phosphorus in their bodies. Phosphorus is a mineral that is important to the health of bones and muscles. When phosphorus levels are too low, it can cause osteomalacia, a condition often described as the weakening of mature bone.
![Aly, a real CRYSVITA patient, walking on a path](/images/why-treat-xlh/jpg/lg/aly.jpg)
Did you know? XLH often runs in the family
XLH is a hereditary condition. People can inherit XLH from either their father or mother. If one member of the family has XLH, there is a good chance that other members may have it, too.
![Family tree showing how XLH is passed down from parents to children](/images/why-treat-xlh/jpg/lg/do-u-know.jpg)
In adults, XLH may cause:
Managing XLH in adults
Be sure to talk to your doctor about treatment goals and options.
Treatment goals for adults with XLH include:
Learn about the possibilities of treating XLH with CRYSVITA
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Stay informed
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