Definition
Rickets is disease resulting from a vitamin D shortage in children. It causes bones to soften and weaken.
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- Outdated tetracycline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.
- Your child’s bodily fluid and bone may be tested. This can be done with:
- Blood tests
- Urine tests
- Bone biopsy —when other tests are not conclusive
- Pictures may be taken of structures inside your child’s body. This can be done with an x-ray.
Treatment
Treatment attempts to:
- Correct the underlying cause
- Relieve or reverse symptoms
Treating the Underlying Cause
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
Treating Symptoms
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.