Vitamin D Deficiency

What is Vitamin D Deficiency?

Vitamin D deficiency, which can cause rickets, is a deficiency disease of infants and children in which bones are not mineralized. Children ages 3-36 months are most at risk. In rickets, bones become soft (producing osteomalacia) and may bend, distort, and/or fracture. Rickets is one of the most common childhood diseases in many developing countries.

Cause of Vitamin D Deficiency

In orphans, rickets is largely due to a prolonged lack of direct exposure to sunlight and/or a lack of Vitamin D and calcium in the diet. Vitamin D acts as a hormone that regulates calcium and phosphorous levels in the bones. Without enough Vitamin D, the body does not properly absorb calcium and phosphorous. When the body senses the calcium and phosphorous imbalance in the bloodstream, it takes calcium and phosphorous from the bones to raise the levels in the bloodstream. As a result, the bones become soft and weak.

Symptoms of Vitamin D Deficiency

Bone pain or tenderness
Skeletal deformity, including bowed legs, windswept knees, boxy forehead, abnormal curvature of the spine, and/or breastbone projection in the chest
Dental problems, including defects in tooth structure, increased chance of cavities, poor enamel, and delayed formation of teeth
Increased tendency for fractures, especially greenstick fractures
Poor growth in height or limbs
Muscle spasms

Implications of Vitamin D Deficiency

Although rickets is easily treated once it is diagnosed, it can lead to severe complications if left untreated. Complications can include motor delays, skeletal deformities, and chronic growth problems that can result in short stature, seizures, and dental defects.

Diagnosis of Vitamin D Deficiency

Vitamin D deficiency is diagnosed by measuring the level of 25-hydroxy-vitamin D (25-OH-D) in the blood serum. The normal concentration of this form of vitamin D ranges from 25 to 50 ng/ml. Deficiency occurs when this level decreases to about 11 or 12 ng/ml or less.

Rickets is diagnosed by x-ray.. A distinct pattern of irregularities and abnormalities of the bones can be clearly seen if a child has rickets. Measurements of blood plasma 25-OH-D, blood plasma calcium, and blood plasma parathyroid hormone must also be obtained for the diagnosis of this disease.

Treatment of Vitamin D Deficiency

Treatment of rickets involves vitamin D supplementation, increasing dietary intake of calcium, phosphates, and vitamin D, along with daily exposure to small amounts of sunlight. Approximately 15 minutes a day of exposure to sunshine can prevent rickets in lighter skinned children. Darker skinned children need longer exposure to the ultraviolet rays of sunshine. In severe cases of rickets with skeletal deformities, the child may benefit from special braces to position the bones appropriately as they grow. Very severe skeletal deformities may require surgery.

Food Sources of Vitamin D

Cod liver oil, egg yolks, butter, salmon, shrimp, cod, milk, and breakfast cereals that are fortified with synthetic vitamin D.