Signs and symptoms of XLH in children

Alejandro, living with XLH

In XLH, the body loses a lot of phosphate through the urine, which decreases the amount of phosphate in the body. Low phosphate levels can prevent the normal development of bones, muscles, and teeth, especially during childhood when most of the growth is taking place. Rickets is a common symptom of XLH that results from the softening of bones, causing them to bend or bow under weight. Rickets leads to other symptoms of XLH such as bowed legs, bone and joint pain, and short stature. As XLH progresses, new symptoms may appear or worsen and may even limit physical ability in children. The appearance of symptoms may vary widely among children. Understanding how these symptoms may affect daily life can help you and your child prepare for the challenges ahead.

Phosphate plays an important role in the development and growth of bones. Low phosphate leads to osteomalacia and rickets in children. Osteomalacia is the softening of bones due to poor bone mineralization. Rickets occurs when the softening of bones happens at the growth plates.



Delayed growth is a symptom of XLH

Delayed growth and short stature are common

Deformities of the legs are symptoms of XLH

Lower limb abnormalities like bowed legs and knock-knees

Bone and joint pain are symptoms of XLH

Bone and joint pain due to rickets and osteomalacia, which is the softening of the bones

Craniosynostosis is a symptom of XLH

Irregularities in the shape of the head, called craniosynostosis

Headaches may be from Chiari malformations due to XLH

Headaches may be due to a condition called Chiari malformation, where brain tissue may occupy space in part of the spinal canal

Rickets and osteomalacia can cause pain and impaired physical activity
Healthy bones support the normal development of muscles in the body. Low phosphate levels, which result in poor bone health, also have a related impact on the muscles’ ability to function properly.



Muscle weakness is a symptom of XLH

Muscle weakness

Muscle stiffness is a symptom of XLH

Muscle stiffness

Muscle pain is a symptom of XLH

Muscle pain

Weakened leg muscles can lead to a wobbly walk (waddling gait) and impaired physical ability

Like bones, the health of teeth also depends on the amount of phosphate in the body. Low phosphate levels can result in dental defects.



Tooth abscesses are a symptom of XLH

Tooth abscesses

Irregular tooth spacing is a symptom of XLH

Irregular tooth spacing

Dental defects may lead to pain, tooth infections, and eventual tooth loss