Definition

What is hypophosphatasia?

hypophosphatasia (HPP) is a rare genetic disorder characterized by the abnormal development of bones and teeth. This condition arises due to lack of mineralization which is a process in which calcium and phosphorus are deposited for development of bones and teeth. These minerals are required for proper hardness and strength. Defective mineralization results in bones that are soft and prone to fracture and deformity. Defective mineralization of teeth can lead to premature tooth loss. The specific symptoms can vary greatly from one person to another, sometimes even among members of the same family.

How common is hypophosphatasia?

hypophosphatasia is not common. It can be managed by reducing your risk factors. Please discuss with your doctor for further information.

Symptoms

What are the symptoms of hypophosphatasia?

The signs and symptoms of hypophosphatasia are extremely varied and can be observed at birth or in adulthood but the most severe form of hypophosphatasia occurs at birth and early infancy.

hypophosphatasia tends to make the bones weak and soft similar to a medical condition found in children called rickets.

Infants with hypophosphatasia are born with relatively short limbs, abnormally shaped chest, and soft skull bones along with extremely poor feeding, inability to gain weight, respiratory difficulties, and presence of hypercalcemia, which causes frequent vomiting episodes and renal problems. In some cases, these symptoms can be potentially serious.

hypophosphatasia appearing in adulthood are much milder than those in infancy. Premature loss of milk teeth is one of the first signs of hypophosphatasia in children. Affected children tend to have a short stature along with bowing of legs. They also will have enlarged wrists and ankle joints. In adult forms of hypophosphatasia, there will be presence of osteomalacia. There will also be frequent fractures of bones in the feet with chronic pain in the foot.

There may be some symptoms not listed above. If you have any concerns about a symptom, please consult your doctor.

When should I see my doctor?

If you have any signs or symptoms listed above or have any questions, please consult with your doctor. Everyone’s body acts differently. It is always best to discuss with your doctor what is best for your situation.

Causes

What causes hypophosphatasia?

hypophosphatasia is caused as a result of a molecular defect in gene encoding TNSALP. TNSALP is an ectoenzyme present in the outer surface of osteoblast and chondrocyte cell membranes. The function of TNSALP is to hydrolyze inorganic pyrophosphate and pyridoxal 5′-phosphate, which is a major form of vitamin B6. When this ectoenzyme TNSALP is low, inorganic pyrophosphate gets accumulated extracellularly and inhibits formation of hydroxyapatite resulting in medical condition called rickets in infants and children and osteomalacia in adults.

Risk factors

What increases my risk for hypophosphatasia?

Please consult with your doctor for further information.

Diagnosis & treatment

The information provided is not a substitute for any medical advice. ALWAYS consult with your doctor for more information.

How is hypophosphatasia diagnosed?

One of the first symptoms of hypophosphatasia is the premature fall of milk teeth in children which can be a telling finding for diagnosis of hypophosphatasia.

  • Laboratory testing: When a laboratory testing is conducted, there will be increased level of pyridoxal 5′-phosphate plasma. Additionally, there will be increased levels of phosphoethanolamine in the urine.
  • Radiographicstudies: X-rays are quite conclusive in the diagnosis of hypophosphatasia, especially in infants and reveal the characteristic abnormalities noted in hypophosphatasia. Some of the radiologic evidence of skeletal defects includes hypomineralization, incomplete vertebral ossification, and occasionally presence of bony spurs on the ulna and fibula.
  • Genetic testing: All the subtypes of hypophosphatasia have been linked to genetic mutations in gene TNSALP, which can be found on detailed genetic testing and can confirm the presence of hypophosphatasia.

How is hypophosphatasia treated?

As of now, there is no cure for hypophosphatasia and treatment is aimed at decreasing morbidity associated with hypophosphatasia. Routine examination of children to look for increased intracranial pressure is essential. Orthopedic care is also required in adults to take care of the fractures. Routine visit to a dentist is also essential. Some treatments which have been tried for treatment of hypophosphatasia but with not so positive results are zinc, magnesium, cortisone, and plasma.

Lifestyle changes & home remedies

What are some lifestyle changes or home remedies that can help me manage hypophosphatasia?

If you have any questions, please consult with your doctor to better understand the best solution for you.

Hello Health Group does not provide medical advice, diagnosis or treatment.

Sources

Review Date: February 22, 2018 | Last Modified: February 22, 2018

Want to live your best life?
Get the Hello Doktor Daily newsletter for health tips, wellness updates and more.