rickets. vitamin d vitamin d is a group of fat-soluble prohormones the two major forms of which are...
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Rickets
Vitamin D
•Vitamin D is a group of fat-soluble prohormones• the two major forms of which are vitamin D2( ergocalciferol( and vitamin D3( cholecalciferol).
•Vitamin D3 is produced in skin exposed to sunlight, specifically ultraviolet B radiation.•Several forms (vitamers) of vitamin D have been discovered (D1-5)The two major forms are vitamin D2 and vitamin D3. These are known collectively as calciferol.•.
Role of Vitamin D • Vitamin D plays an important role in the
maintenance of organ systems:• its regulates the calcium and phosphorus
levels in the blood by promoting their absorption from food in the intestines, and by promoting re-absorption of calcium in the kidneys, which enables normal mineralization of bone and prevents hypocalcemic tetany. It is also needed for bone growth and bone remodeling by osteoblasts and osteoclasts
• Vitamin D2 is derived from fungal and plant sources, and is not produced by the human body.
• Vitamin D3 is derived from animal sources and is made in the skin when 7-dehydrocholesterol reacts with UVB ultraviolet light
• In the absence of vitamin K or with drugs (particularly blood thinners) that interfere with Vitamin K metabolism, Vitamin D can promote soft tissue calcification
• It inhibits parathyroid hormone secretion from the parathyroid gland.
• affects the immune system by promoting phagocytosis, anti-tumor activity, and immunomodulatory functions.
Vitamin D deficiency
• Vitamin D deficiency can result from inadequate intake coupled with inadequate sunlight exposure.
• disorders that limit its absorption, conditions that impair conversion of vitamin D into active metabolites, such as liver or kidney disorders, or, rarely, by a number of hereditary disorders.
Deficiency results in impaired bone mineralization, and leads to bone softening diseases, rickets in children and osteomalacia in adults, and possibly contributes to osteoporosis.
However, sunlight exposure, to avoid deficiency, carries other risks, including skin cancer; this risk is avoided with dietary absorption, either through diet or as a dietary supplement.
Vitamin D Sources
1-Sun Exposure as a Vitamin D Source:
•UVB rays UVB rays produce vitamin D in the body. You can get UVB rays from the sun•Ten to fifteen minutes of sun exposure at least two times per week to the face, arms, hands, or back without sunscreen is usually sufficient to provide adequate vitamin D.
Vitamin D Sources 2-Foods with Vitamin D:
Vitamin D is available in some foods. This is a safe way to get vitamin D: fatty fish, such as salmon and sardines, are the main natural sources. Most vitamin D in the diet comes from fortified foods including all cows’ milk.
3-Supplements :Supplements are a safer form of vitamin D, speak to your doctor to find out if you need to take a supplement.
Foods with Vitamin D
Food
Pure Cod liver oil, 1 Tablespoon (Note: most refined cod liver oils today have the vitamin D removed! Check your label to be certain.)
Salmon, cooked, 3½ ounces
Mackerel, cooked, 3½ ounces
Tuna fish, canned in oil, 3 ounces
Sardines, canned in oil, drained, 1¾ ounces
Milk, nonfat, reduced fat, and whole, vitamin D fortified, 1 cup
Margarine, fortified, 1 Tablespoon
Pudding, prepared from mix and made with vitamin D fortified milk, ½ cup
Ready-to-eat cereals fortified with 10% of the DV for vitamin D, ¾ cup to 1 cup servings (servings vary according to the brand)
Egg, 1 whole (vitamin D is found in egg yolk)
Liver, beef, cooked, 3½ ounces
Cheese, Swiss, 1 ounce
Rickets
Rickets is the softening and weakening of bones in children, usually because of an extreme and
prolonged vitamin D deficiency .
Vitamin D absorption of calcium and phosphorus from the GIT, which child needs to build strong bones .
A deficiency of vitamin D difficult to maintain proper calcium and phosphorus levels in bones .
If a vitamin D or calcium deficiency causes rickets, adding vitamin D or calcium to the diet generally corrects any resulting bone problems
child .
Rickets due to a genetic condition may require additional medications or other treatment. Some skeletal deformities caused by rickets may need corrective surgery
Symptoms
Vitamin D deficiency begins slowly before physical signs and symptoms of rickets appear .
When rickets signs and symptoms develop, they may include :Skeletal deformities. These include bowed legs, abnormal curvature of the spine, pelvic deformities and breastbone projection in the
chest .
Fragile bones. Children with rickets are more prone to bone fractures .
Impaired growth. Delayed growth in height or limbs may be a result of rickets.
Dental problems. These include defects in tooth structure, increased chance of cavities, poor
enamel and delayed formation of teeth .
Bone pain. This includes dull, aching pain or tenderness in the spine, pelvis and legs .
Muscle weakness. Decreased muscle tone may make movement uncomfortable .
Causes
Vitamin D acts as a hormone to regulate calcium and phosphorus levels in bones .
imbalance of calcium and phosphorus in your bloodstream, it reacts by taking calcium and phosphorus from bones.
This softens or weakens the bone structure, which can result in skeletal deformities, such as bowlegs or improper curvature of the spine.
Osteomalacia is the adult version of rickets .
Risk factors
Lack of vitamin DBreast-fed infants who don't receive supplemental vitamin D are at increased risk of developing rickets because although vitamin D does cross from mother to baby in the breast milk, it's not enough to prevent a deficiency. While exposure to sunlight could produce the necessary amounts of vitamin D
sunburn and skin cancer are real dangers.
Sunscreens, which are used to protect against these dangers, can decrease vitamin D production by blocking the sun's ultraviolet rays.
Lack of calcium and phosphorus Children who don't get enough calcium and
phosphorus in their diets are at increased risk of rickets .
Complications
Delays in your child's motor skills development Failure to grow and develop normally Skeletal deformities
Chronic growth problemSeizures Dental defects
Tests and diagnosis
Physical examinationcheck if the pain or tenderness is coming directly
from the bones, instead of the joints and muscles surrounding them .
Blood tests These measure calcium and phosphorus levels to see if they're normal .
X-rays images of affected bones to look for softening or weakness .
Medical history Kidney problems
Treatments and drugs
The aim of treatment for rickets Improvement generally occurs within three months .
a vitamin D supplement increase your intake of vitamin D-fortified foods, including
fortified breakfast cereal, orange juice, fish and processed milk .
Getting a sufficient intake of calcium is crucial to maintaining healthy bones
appropriate level of calcium intake depending on age and whether you have absorption problems.
The combination of increased vitamin D intake with calcium may be enough to eliminate the effects of rickets entirely .
Vitamin D supplements
The American Academy of Pediatrics (AAP) recommends that all breast-fed infants receive 400 international units (IU) of oral vitamin D daily beginning during the first two months of life and continuing until the daily consumption of vitamin D-fortified formula or milk is two to three glasses, or 500 milliliters (mL).
AAP also recommends that all children and adolescents should receive 400 IU a day of vitamin D .
Vitamin D supplements for infants generally come in droplet form.
Use only supplements that contain up to 400 IU of vitamin D per mL or tablet .
Recommended daily intake of calcium is as follows (serving sizes vary with age) :
1 to 3 years of age. 500 milligrams (mg) (two servings of dairy products a day)
4 to 8 years of age. 800 mg (two to three servings of dairy products a day) 9 to 18 years of age. 1,300 mg (four servings of dairy products a day)
19 to 50 years of age. 1,000 mg a day (three servings of dairy products a day)
Older than 50. 1,200 mg a day (nearly four servings of dairy products daily) Milk and dairy products are common sources of calcium. Other sources of calcium include leafy green vegetables (for example, spinach), fortified orange juices, fortified breakfast cereals and calcium supplements
Thank you
Done by : Rfaah Al-
Ajmy
Afnan Al-Addad
Nouf Al-Fadel
Supervised by :
Dr- Ghadah Fawzi
References
http://www.mayoclinic.com/health/rickets/DS00813
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