What are the symptoms of hypophosphatasia (HPP)?

The symptoms of HPP may vary from mild to severe and may present differently based on age of onset. Symptoms can also change within the same person over time. HPP can affect bones and teeth, but there are other perplexing symptoms of this metabolic bone disease that form a larger picture of HPP.

Some symptoms of HPP may include:

Skull and Brain

  • Premature closure of skull bones, leading to abnormally shaped head*
  • Anxiety and depression
  • Seizures*
  • Headaches
  • Fatigue


  • Early tooth loss with the root intact
  • Receding gums


  • Improper development of ribs and chest deformities*
  • Difficulty breathing and breathing complications
  • Increased risk of pneumonia


  • Calcium buildup in the kidneys
  • Kidney failure


  • Rickets
  • Chronic bone pain
  • Frequent or slow-healing fractures
  • Weak bones or bowed legs

Joints and Muscles

  • Weakness
  • Pain
  • Arthritis
  • Gout-like symptoms
  • Muscle fatigue
  • Missed motor milestones
  • Mobility issues that may require an assistive device

*Symptoms commonly seen in infants and young children.
This is not an exhaustive list of HPP signs and symptoms.