Rickets

Definition

Rickets is disease that affects the bones. It causes them to soften and weaken.

Rickets

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Causes

Rickets is caused by a vitamin D, calcium, or phosphorous shortage a child's body. This may occur when:

• The supply of vitamin D from diet or sun exposure is too low
• The way the body processes vitamin D is not typical
• Tissue does not respond to the action of vitamin D
• There is not enough calcium or phosphorous in the diet or it cannot be absorbed

Less often, rickets can be caused by other disorders that affect vitamin D absorption or calcium metabolism such as:

• Kidney problems:
  • A hereditary disorder of the kidney called vitamin D-resistant rickets
  • Renal tubular acidosis—a non-hereditary kidney disorder that causes bone calcium to dissolve
  • Chronic kidney failure
  • Long-term kidney dialysis
• Malabsorption-related diseases of the small intestine
• Liver or pancreatic diseases
• Cancer
• Certain medications
• Poisoning from:
  • Cadmium
  • Lead
  • Aluminum
  • Outdated tetracycline

Risk Factors

Rickets is more common in children aged 6-24 months. It is also more common in children of African American descent.

Factors that may increase your child's chances of getting rickets include:

• Lack of sun exposure or having dark skin
• Babies who are breastfed—breast milk is low in vitamin D
• Babies who do not drink enough formula that is fortified with vitamin D
• Children who do not drink enough vitamin D-fortified milk
• Lactose intolerance with low intake of vitamin D-fortified milk
• Vegetarian diet
• Family history of rickets
• Certain chronic illnesses that result in loss of or poor absorption of calcium or phosphorous
• Drugs that affect vitamin D, calcium, or phosphorous

Symptoms

Symptoms may include:

• Muscle weakness
• Bow legs or knock knees
• Bone pain and tenderness
• Skeletal and/or skull deformities
• Deformity or curvature of the spine—scoliosis
• Pigeon chest—a chest that protrudes
• Dental deformities
• Delayed tooth formation
• Defects in teeth
• Loss of appetite or weight loss
• Difficulty sleeping
• Delayed walking
• Seizures

Diagnosis

You will be asked about your child's symptoms and medical history. A physical exam will be done.

Your child's bodily fluids and bone may be tested. This can be done with:

• Blood tests
• Urine tests
• Bone biopsy

Pictures may be taken of structures inside your child's body. This can be done with an x-ray.

Treatment

Treatment attempts to:

• Relieve or reverse symptoms and improve bone changes
• Correct the underlying cause

Treating Symptoms

Treatment to relieve or correct symptoms and bone changes:

• Involves biologically active vitamin D, calcium, and/or phosphate
• May include:
  • Wearing braces to reduce or prevent bony deformities
  • In severe cases, surgery to correct bony deformities

Treating the Underlying Cause

Treatment of the underlying cause may include:

• Adding the following to your child's diet:
  • Supplements of vitamin D, calcium, and other minerals
  • Vitamin D-fortified dairy products
  • Foods high in vitamin D, such as fatty fish, egg yolk, and green vegetables
  • Foods high in calcium
• Adequate, but not excessive, exposure to sunlight
• Avoiding medication that may be causing poor calcium, phosphorous, or vitamin D absorption
• Treating underlying illnesses

Prevention

To help reduce your child's chance of rickets:

• Drink vitamin D-fortified milk.
• Consume enough vitamin D, calcium, and other minerals. If you think your child's diet may be lacking, talk with the doctor about other sources of vitamins and minerals.
• Get sufficient, but not excessive, exposure to sunlight. Fifteen minutes a day is usually enough. Any longer than that requires sun protection with clothing or sunscreens, especially in fair-skinned infants and children. Children with dark skin are at increased risk for rickets and may need more sun exposure and dietary supplements with vitamin D.
• Breastfed babies and bottle-fed babies who do not get enough vitamin-D fortified formula may need to be given a supplement starting within the first few days of life. Talk to the doctor to make sure your child is meeting the nutritional requirements for vitamin D.