Definition | Causes | Risk Factors | Symptoms | Diagnosis | Treatment | Prevention

Definition

Rickets is disease resulting from a vitamin D shortage in children. It causes bones to soften and weaken.

Rickets

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Causes

Rickets results when there is a vitamin D or calcium shortage in 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.

Vitamin D controls how calcium is absorbed in the body. It also controls levels of calcium and phosphate in bone. Vitamin D is absorbed in the intestines from food. Vitamin D is also produced by the skin during exposure to sunlight.

Most often, rickets is caused by a shortage of vitamin D. This can result from:

  • Not enough vitamin D in the diet. In children, this may be related to:
    • Not drinking enough vitamin D-fortified milk
    • Not giving enough vitamin D supplements to children being breastfed or to children who are lactose intolerant
  • Lack of exposure to sunlight

Less often, rickets can be caused by other disorders that affect vitamin D absorption, processing, or action in the body 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
  • Diseases of the small intestines with malabsorption
  • Disorders of the liver or pancreas disease
  • Cancer
  • Certain drugs, such as:
    • Certain seizure medications, such as phenytoin or phenobarbital
    • Acetazolamide
    • Ammonium chloride
    • Disodium etidronate
    • Fluoride treatment
  • Toxicity or poisoning from:
    • Cadmium
    • Lead
    • Aluminum
    • Outdated tetracycline

Risk Factors

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

  • Lack of sun exposure
  • Age in children: 6 to 24 months
    • 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
  • Family history of rickets
  • Race: Black, especially in association with breastfeeding
  • Certain chronic illnesses that result in loss of or poor absorption of calcium

Symptoms

Symptoms may include:

  • Bone pain and tenderness
  • Skeletal and/or skull deformities
  • Bow legs or knock knees
  • Deformity or curvature of the spine
  • Pigeon chest—a chest that protrudes
  • Impaired growth, resulting in short stature
  • Bone fractures
  • Dental deformities
  • Delayed tooth formation
  • Defects in teeth
  • Increased cavities
  • Loss of appetite or weight loss
  • Difficulty sleeping
  • Poor muscle development and tone
  • Muscle weakness
  • Delayed walking

Diagnosis

The doctor will ask about your child's symptoms and medical history. A physical exam will be done.

Treatment

Treatment attempts to:

  • Correct the underlying cause
  • Relieve or reverse symptoms

Treatment of the underlying cause may include:

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

Treatment to relieve or correct symptoms may include:

  • Wearing braces to reduce or prevent bony deformities
  • In severe cases, surgery to correct bony deformities

Prevention

To help prevent rickets, your child should:

  • Drink vitamin D-fortified milk.
  • Consume enough vitamin D, calcium, and other minerals. If you think your child's diet may be deficient, 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 supplementation 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. Children not getting at least 400 units of vitamin D from their diet may also need supplements. Talk to the doctor to make sure your child is meeting the nutritional requirements for vitamin D.