Rickets is a childhood bone disorder where bones soften and become prone to fractures and deformity. It is the softening and weakening of bones in children, usually because of an extreme and prolonged vitamin D deficiency. It is a skeletal disorder. It is rare in industrialized nations, but fairly common in some developing countries.
Although it can occur in adults, the majority of cases occur in children suffering from severe malnutrition, usually resulting from famine or starvation during the early stages of childhood. Osteomalacia is a similar condition occurring in adults, caused by deficiencies of vitamin D, phosphate or calcium.
Vitamin D promotes the absorption of calcium and phosphorus from the gastrointestinal tract. A deficiency of vitamin D makes it difficult to maintain proper calcium and phosphorus levels in bones, which can cause rickets. These nutrients are important for the development of strong, healthy bones.
Rickets may lead to skeletal deformity and short stature. In females, pelvic distortion from rickets may cause problems with childbirth later in life. Severe rickets has been associated with respiratory failure in children.
Signs and Symptoms
Signs and symptoms of rickets can include:
Pain in the spine, pelvis and legs
Because rickets softens the growth plates at the ends of a child's bones, it can cause skeletal deformities such as:
Bowed legs or knock knees
Thickened wrists and ankles
When to see a Doctor
Call your doctor right away if your child is showing signs of rickets. If the disorder isn’t treated during a child’s growth period, the child may end up with a very short stature as an adult. Deformities can also become permanent if the disorder goes untreated.
Your body needs vitamin D to absorb calcium and phosphorus from food. Rickets can occur if your child's body doesn't get enough vitamin D or if his or her body has problems using vitamin D properly. Occasionally, not getting enough calcium or lack of calcium and vitamin D can cause rickets.
Lack of vitamin D
Children who don't get enough vitamin D from these two sources can develop a deficiency:
Sunlight. Your skin produces vitamin D when it's exposed to sunlight. But children in developed countries tend to spend less time outdoors. They're also more likely to use sunscreen, which blocks the rays that trigger the skin's production of vitamin D.
Food. Fish oils, fatty fish and egg yolks contain vitamin D. Vitamin D also has been added to some foods, such as milk, cereal and some fruit juices.
Problems with absorption
Some children are born with or develop medical conditions that affect the way their bodies absorb vitamin D. Some examples include:
Inflammatory bowel disease
In rare cases, children can be born with a genetic form of rickets.
Factors that can increase a child's risk of rickets include:
Dark skin. Dark skin doesn't react as strongly to sunshine as lighter skin, so it produces less vitamin D.
Mother's vitamin D deficiency during pregnancy. A baby born to a mother with severe vitamin D deficiency can be born with signs of rickets or develop them within a few months after birth.
Geographical location. Children who live in geographical locations where there is less sunshine are at higher risk of rickets.
Premature birth. Babies born before their due dates are more likely to develop rickets.
Medications. Certain types of anti-seizure medications and antiretroviral medications, used to treat HIV infections, appear to interfere with the body's ability to use vitamin D.
Exclusive breast-feeding. Breast milk doesn't contain enough vitamin D to prevent rickets. Babies who are exclusively breast-fed should receive vitamin D drops.
If left untreated, rickets can lead to:
Failure to grow
Abnormally curved spine
During the exam, the doctor will gently press on your child's bones, checking for abnormalities. He or she will pay particular attention to your child's:
Babies who have rickets often have softer skull bones and might have a delay in the closure of the soft spots (fontanels).
Legs. While even healthy toddlers are a little bowlegged, an exaggerated bowing of the legs is common with rickets.
Chest. Some children with rickets develop abnormalities in their rib cages, which can flatten and cause their breastbones to protrude.
Wrists and ankles. Children who have rickets often have wrists and ankles that are larger or thicker than normal.
X-rays of the affected bones can reveal bone deformities. Blood and urine tests can confirm a diagnosis of rickets and also monitor the progress of treatment.
Adding vitamin D or calcium to the diet generally corrects the bone problems associated with rickets.
Most cases of rickets can be treated with vitamin D and calcium supplements. Follow your child's doctor's directions as to dosage. Too much vitamin D can be harmful.
When rickets are due to another underlying medical problem, your child may need additional medications or other treatment.
Your child's doctor will monitor your child's progress with X-rays and blood tests.
Surgical and other procedures
For some cases of bowlegs or spinal deformities, your doctor might suggest special bracing to position your child's body appropriately as the bones grow. More-severe skeletal deformities might require surgery.
Increasing vitamin D, calcium, and phosphate levels will help correct the disorder. Most children with rickets see improvements in about one week.
Skeletal deformities will often improve or disappear over time if rickets is corrected while the child is still young. However, skeletal deformities can become permanent if the disorder isn’t treated during a child’s growth period.
Exposure to sunlight provides the best source of vitamin D. During most seasons, 10 to 15 minutes of exposure to the sun near midday is enough. However, if you're dark-skinned, if it's winter or if you live in northern latitudes, you might not be able to get enough vitamin D from sun exposure.
In addition, because of skin cancer concerns, infants and young children, especially, are warned to avoid direct sun or to always wear sunscreen and protective clothing.
To prevent rickets, make sure your child eats foods that contain vitamin D naturally such as fatty fish, fish oil and egg yolks, or that have been fortified with vitamin D, such as:
Milk, but not foods made from milk, such as yogurt and cheese
Check labels to determine the vitamin D content of fortified foods.
If you're pregnant, ask your doctor about taking vitamin D supplements.
Because human milk contains only a small amount of vitamin D, all breast-fed infants should receive 400 international units (IU) of oral vitamin D daily.
Currently, studies are unclear about how much vitamin D is enough in certain populations, but the current recommendation is for at least 400 IU daily.
Given the fact that vitamin D supplementation may not be readily available worldwide, more research needs to be performed to determine the "safe" amount of sunlight exposure for infants and children if we are going to successfully prevent rickets throughout the world.