X-linked hypophosphataemic rickets and phosphate-wasting bone disease
X-linked hypophosphataemic rickets, often shortened to XLH, is a rare inherited condition that causes low phosphate levels and impaired bone mineralisation. It can affect bones, teeth, growth, joints, mobility and long-term skeletal health.
XLH can continue to affect people into adulthood, even when first recognised in childhood. Specialist review can help assess symptoms, phosphate levels, fractures, bone pain and long-term treatment planning.
XLH affects the way the body handles phosphate, a mineral needed for strong bones and teeth.
Phosphate is essential for normal bone mineralisation. In XLH, the kidneys lose too much phosphate into the urine, causing persistently low phosphate levels in the blood. This can lead to rickets in childhood and osteomalacia, bone pain, fractures or pseudofractures in adulthood.
The condition is usually linked to changes in the PHEX gene and increased FGF23 activity. Symptoms vary widely. Some people are diagnosed in childhood because of bowed legs or growth problems, while others need adult review because of pain, stiffness, dental problems, fractures or ongoing treatment questions.
- Specialist assessment of suspected or confirmed XLH
- Review of low phosphate, bone pain, fractures, dental history and mobility
- Advice on adult complications, monitoring and long-term rare bone disease care
- Support with treatment planning and research or emerging therapy pathways where relevant
What XLH can look like
XLH can affect people differently across childhood and adulthood. Adult symptoms may include bone pain, joint stiffness, fractures, dental problems, muscle weakness, enthesopathy and reduced mobility.
Low phosphate
Persistently low serum phosphate is a key feature and needs interpretation with other blood and urine tests.
Bone pain
Adults may experience bone pain, aching or pain linked to osteomalacia, fractures or pseudofractures.
Lower limb bowing
Some patients have bowed legs or skeletal alignment changes that began during childhood.
Fractures or pseudofractures
Poor bone mineralisation can increase the risk of stress fractures, pseudofractures or slow healing.
Dental problems
Dental abscesses, tooth problems or early tooth loss may occur even when dental hygiene is good.
Joint stiffness and mobility issues
Joint pain, stiffness, enthesopathy and osteoarthritis can affect movement, function and quality of life.
Why XLH happens
XLH is usually caused by a change in the PHEX gene. This leads to increased activity of FGF23, a hormone that causes the kidneys to lose too much phosphate in the urine.
The condition is inherited in an X-linked pattern. Both males and females can be affected, and the severity can vary even within families.
How XLH is assessed
Assessment may include blood phosphate, calcium, alkaline phosphatase, vitamin D, parathyroid hormone, kidney function, urine phosphate handling, imaging, fracture history and dental history.
Genetic testing may be relevant where the diagnosis is uncertain or family counselling is needed. A specialist review helps connect symptoms, test results, imaging and previous treatment history.
XLH is not only a childhood condition
Many people with XLH continue to experience symptoms in adulthood. These may include bone pain, joint stiffness, osteoarthritis, enthesopathy, fractures, dental complications and reduced stamina.
A specialist adult bone health review can help assess current disease impact, treatment history, complications and whether newer or research-linked treatment pathways may be relevant.
Related treatments and services
X-linked hypophosphataemic rickets is a rare inherited phosphate-wasting condition that can affect bone strength, bone shape, pain, mobility and fracture risk. Specialist assessment can help review symptoms, blood results, bone density and wider metabolic bone health needs.
A specialist consultation for XLH and phosphate-wasting bone disease
Professor Keen will review your diagnosis, phosphate results, previous treatment, symptoms, fracture history, dental history, imaging, family history, mobility, pain and any previous specialist care.
The consultation can help clarify current disease impact, whether further assessment is needed and what monitoring, treatment or research-linked pathways may be suitable.
XLH questions
Common questions from patients with X-linked hypophosphataemic rickets, low phosphate or suspected phosphate-wasting bone disease.
What is X-linked hypophosphataemic rickets?
X-linked hypophosphataemic rickets is a rare inherited condition that causes phosphate wasting through the kidneys. Low phosphate affects bone mineralisation and can lead to rickets, osteomalacia, pain and fractures.
Does XLH only affect children?
No. XLH often begins in childhood but can continue to cause symptoms in adults, including bone pain, joint stiffness, dental problems, fractures, pseudofractures and mobility issues.
How is XLH diagnosed?
Diagnosis may involve blood phosphate, urine phosphate handling, calcium, vitamin D, PTH, alkaline phosphatase, imaging, clinical history and sometimes genetic testing.
Can XLH be treated?
Yes. Treatment depends on age, symptoms, previous care and availability of specialist therapies. Some patients receive phosphate and active vitamin D, while others may be considered for newer targeted treatment pathways.
When should I seek specialist advice?
Specialist advice is helpful if you have known XLH, low phosphate, bone pain, pseudofractures, fractures, dental problems, stiffness, mobility issues or uncertainty about monitoring and treatment options.
Arrange a specialist XLH appointment
If you have X-linked hypophosphataemic rickets, low phosphate, bone pain, fractures, pseudofractures, dental problems or concerns about rare phosphate-wasting bone disease, please contact the practice.
Contact details
For private appointments and general enquiries, please contact the office.