What is Rickets?
Calcium and phosphorus are minerals which play an important part in maintaining bone
strength. If a child has a problem getting enough calcium and phosphorus into the
bones, he or she can develop rickets. Only children can develop rickets, although
there is a similar condition in adults called osteomalacia.
What Causes Rickets?
- When there isn’t enough calcium and phosphorus around, the bones don’t grow as well
and become weak. Any condition that decreases the amount of calcium and phosphorus
available to the bones can cause rickets.
- Vitamin D deficiency is the most common cause of rickets. Vitamin D is a hormone that
is made by the body through exposure to the sun or is taken as a vitamin. Without
enough vitamin D, the body is not able to absorb enough calcium and phosphorus from
food. If this goes on for a long time rickets can develop.
- Kidney disease. Some children are born with or develop kidneys that don’t work well.
If they kidneys are damaged, too much calcium and phosphorus can be lost in the urine.
- Malabsorption. Some children who have severe gastrointestinal or liver disease have
trouble absorbing enough vitamin D, calcium, and phosphorus from their diet.
- Tumors. There are rare types of tumors that can cause the kidney to lose too much
phosphorus into the urine. This condition is known as tumor-induced osteomalacia.
- Some children can develop rickets as a result of a genetic condition present at birth.
Names of these conditions include:
- X-linked hypophosphatemic rickets (XLH)
- Hereditary hypophosphatemic rickets with hypercalciuria
- Vitamin D-dependent rickets type I (also known as 1-alpha-hydroxylase deficiency)
- Vitamin D-dependent rickets type II (also known as vitamin D resistance)
What are the Symptoms of Rickets?
- Bowing of the legs
- Widening of the wrists
- Broken bones
- Delayed closure of the fontanels (soft spot) in the skulls in infants
- Soft and squishy skull bones (craniotabes)
- Poor growth and short stature
- Muscle weakness
- Muscle spasm
- Muscle cramps
How is Rickets Diagnosed?
- Laboratory tests: Blood and urine tests will be done to look at the levels of calcium,
phosphorus, vitamin D, and other hormones in the blood and urine
- Xrays: This may include just one X-ray of the wrist or x-rays of the whole body (skeletal
survey). Xrays may show signs of rickets including “metaphyseal widening” or a “rachitic
- Genetic tests: Blood may be sent for genetic testing if one of the genetic diagnoses
listed above is suspected.
How is Rickets Treated?
Treatment will depend on what type of rickets your child has. Vitamin D deficiency
rickets will be treated with high doses of vitamin D and calcium given by mouth. Both
liquid and pill forms are available. Some patients will be treated with a special
form of vitamin D called “calcitriol”. Patients who have rickets because of low phosphorus
levels may be treated with phosphate. New medicines are being tested specifically
for the treatment of XLH.
What Can I Do to Prevent Rickets in My Child?
You should talk to your doctor to make sure your child is getting enough vitamin D.
Nearly all babies should take 400 IU of vitamin day daily while they are nursing or
taking formula. In Rochester, and other northern cities with long winters, most children
and adults should take a vitamin D supplement, especially in the winter. Talk to your
doctor to discuss what is best for your child.