early and accurate diagnosis is important
X-linked hypophosphatemia (XLH) is often diagnosed in childhood, but some people are not diagnosed until they’re adults because symptoms can vary.
Because XLH can worsen over time, it’s important to diagnose it early and start managing the condition sooner. You know yourself or your child best—if something doesn’t feel right, trust your instincts and talk to a healthcare professional.
Karabeth and her mother, JoBeth
Karabeth is living with XLH
Family history can help confirm a diagnosis
Knowledge of your family's health can help your care team diagnose, treat, and manage XLH. You can start by building your family tree.
Build your family tree
Just knowing that there was an answer and a reason why was probably the best part of learning my diagnosis.
Emily, mother to Isla, both living with XLH
How doctors may diagnose xlh
Doctors use different ways to diagnose XLH, including:
Reviewing your symptoms
X-rays
Blood tests to check phosphorus levels
Genetic testing
Keep in mind that testing for XLH involves several steps. You may need to see more than one doctor to get an accurate diagnosis.
specialists who can help
Because XLH is rare, it helps to see a doctor who understands it. You may need to see specialists, along with your primary care provider, to help manage your condition.
Types of specialists who can diagnose and manage XLH:
Rheumatologists
Care for joints, muscles, and connective tissue
Endocrinologists
Treat issues with hormones, like FGF23
Nephrologists
Monitor and manage kidney function
Geneticists
Diagnose and address genetic conditions
Looking for a doctor who specializes in XLH?
Find a specialist
COMM-US-RDS-0999 August 2026