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Vitamin D status in Jordanian Infants, A Cause for Concern ?. Najwa Khuri-Bulos, MD, FIDSA, Samir Faouri MD Jordan University Hospital and Al Bashir Government Hospital July 2012. Outline about vitamin D. Sources of vitamin D Classical action on bone Non classical functions - PowerPoint PPT Presentation
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Vitamin D status in Jordanian Infants, A Cause for Concern ?
Najwa Khuri-Bulos, MD, FIDSA, Samir Faouri MD Jordan University Hospital and Al Bashir
Government HospitalJuly 2012
Outline about vitamin D– Sources of vitamin D– Classical action on bone – Non classical functions– Normal vitamin D intake– Pts at risk of vitamin D deficiency– Clinical manifestations of vitamin D deficiency– Laboratory diagnosis of vitamin D deficiency– Treatment– Status of vitamin D in jordan with special reference to
children Prevention of vitamin D deficiency
Vitamin D and the fetus and newborn
• What is role of vitamin D in pregnancy• What is the role of vitamin D in labor and birth• What is the role of vitamin D in the newborn• What is the relationship of vitamin D in
mother and the fetus
WHO reference
• Vitamin D deficiency in pregnant women has been associated with an increased risk of pre-eclampsia and gestational diabetes.
• Vitamin D deficiency early in pregnancy is associated with a five-fold increased risk of preeclampsia, according to a study from the University of Pittsburgh Schools of the Health Sciences reported in the Journal of Clinical Endocrinology and Metabolism.
Vitamin D
• Rickets first described in the 17th century• Relationship to fat soluble vitamin and dietary
vitamin D in early 20th century .• This is the only vitamin that is synthesized by
human body by interaction of skin with sunshine• Many genes encoding proteins that regulate cell
proliferation, differentiation, and apoptosis are modulated in part by vitamin D
Vitamin D pathways for the two sources of vitamin D
Definition
• Vitamin D2, Ergosterol plant sources
• Vitamin D3 Cholecalciferol from skin
• also manufactured from lanolin • 25,0H vitamin D Calcidiol• 1,25 OH vitamin D Calcitriol
Vitamin D actions
• Vitamin D promotes calcium absorption in the gut
• Maintains adequate serum calcium and phosphate concentrations to enable normal mineralization of bone and prevents hypocalcemic tetany.
• It is also needed for bone growth and bone remodeling by osteoblasts and osteoclasts
Vitamin D actions
Actions on bone
• Increased Bone density• Increased calcium and PO4 deposition• Decreased osteoporotic fracture
Vitamin D actions
Immune response• Increased regulatory T cell• Increased oxidative burst• Increased Cathelicidin• Decreased cytokine release
Vitamin D actions
Pregnancy• ?Decreased pre eclampsia• Decreased myopathy• Decreased calcium malabsorption• Decreased bone loss• ?Decreased risk of CS Mulligan et al, American Journal of Obstetric and Gynecology, 2010
Vitamin D action
Pancreas• Decreased insulin resistance• Decreased type 1 diabetes• Increased insulin secretion
Vitamin D actions
Children• Decreased SGA• Decreased risk of rickets• Decreased risk of hypocalcemia• Infantile cardiomyopathy if deficient• Decreased severity of RSV infection• Increased incidence of asthma if deficient
Sources of vitamin D
• Normal diets < 10%• Must be synthesized by the skin or taken as
dietary supplement– Skin, must have direct exposure to sunshine 10-15
minutes at noon hours– Exposure not acceptable behind glass– No sun block applied– Dark skin people need more exposure to have
same level of vitamin D
Vitamin D in the newborn
• Highly correlated with vitamin D in the pregnant mother. Fetus totally dependent on maternal sources of vitamin D and Calcium
• After birth, Breast milk is a very poor source of vitamin D, only 10-40 Units/Litre
• Hence Must supplement infants very early in life• Infants need 400 IU/ per day• Even formula fed babies need vitamin D
supplementation
Vitamin D status
• 1 nmole/litre = 0.4 ngm /ml• Vitamin D levels are Inversely related to
parathormone levels• These level off at 30-40 nanograms
determined to be the adequate range• Calcium absorption increased at > 30
nanograms
Vitamin D 25 OH levels and vitamin D status
• Definition– <20ng/ml <50 mm/L
Deficient– 20-30ng/ml 50-75 mm/L
Insufficient– >30- ng/ml >75 mm/L
Normal, optimal– >150 ng/ml >375 mm/L Toxic
Vitamin D sources• Dietary• Supplementation• Sunlight
– Wavelength 290-315 penetrates the skin and converts 7 dehydrocholesterol to previtamin D3
– Any excess of these is destroyed by sunlight. There is no toxicity from sun exposure.
– Vitamin D from the skin and dietary sources is metabolized by the liver to become 25 OH and the final 1 hydroxylation step occurs in the kidney to lead to 1, 25 OH vitamin D which is the active form
– This final renal step is highly regulated by parathormone and serum calcium and PO4 levels
Sun exposure and vitamin D
• Ultraviolet (UV) B radiation with a wavelength of 290–320 nanometers penetrates uncovered skin and converts cutaneous 7-dehydrocholesterol to previtamin D3, which in turn becomes vitamin D3.
Adequate intake of vitamin D per day
• Infants <12 month 400 IU• Children >1 yr 600 IU• Adults, pregnant 600 IU• >70 yrs
800 IU
• Mainly obtained from fish and fortified foods or exposure to sunshine
• 1 ug=40 units
People at risk of vitamin D deficiency
• Breast fed infants• Older adults • People with limited sun exposure• People with dark skin• People with fat malabsorption• People with BMI>30
Causes of vitamin D deficiency in children and adolescents
• Reduced intake or synthesis of vitamin D3– Being born to a vitamin D-deficient mother; dark-
skinned women, or women of who actively avoid exposure to sunlight or are veiled
– Prolonged breastfeeding– Dark skin colour– Reduced sun exposure — chronic illness or
hospitalisation, intellectual disability, and excessive use of sunscreen
– Low intake of foods containing vitamin D
Causes of vitamin D deficiency in children and adolescents
• Abnormal gut function or malabsorption– Small-bowel disorders (eg, coeliac disease)– Pancreatic insufficiency (eg, cystic fibrosis)– Biliary obstruction (eg, biliary atresia)
Causes of vitamin D deficiency in children and adolescents
• Reduced synthesis or increased degradation of 25-OHD or 1,25-(OH)2D– Chronic liver or renal disease– Drugs: rifampicin, isoniazid and anticonvulsants
Osseous signs of vitamin D deficiency (common to less common)
• Swelling of wrists and ankles• Rachitic rosary (enlarged costochondral joints felt lateral to the nipple line)• Genu varum, genu valgum or windswept deformities of the knee• Frontal bossing• Limb pain and fracture• Craniotabes (softening of skull bones, usually evident on palpation of cranial sutures
in the first 3 months)• Hypocalcaemia — seizures, carpopedal spasm• Myopathy, delayed motor development• Delayed fontanelle closure• Delayed tooth eruption• Enamel hypoplasia• Raised intracranial pressure• secondary hyperparathyroidism
Radiological features
• Cupping, splaying and fraying of the metaphysis of the ulna, radius and costochondral junction
• Coarse trabecular pattern of metaphysis• Osteopenia• Fractures
Treatment of Hypocalcemia
< 1 month of age • 10% calcium gluconate: 0.5 mL/kg (max 20 mL)
intravenously over 30–60 minutes.
• Calcium: 40–80 mg/kg/day (1–2 mmol/kg/day) orally in 4–6 doses,
• Calcitriol ( vitamin D3) : 50–100 ng/kg/day or in 2–3 doses until serum calcium level is > 2.1 mmol/L or 8 mg/L
Treatment of vitamin D deficiencyACUTE ManagementAge< 1 month
Vitamin D: 1000 IU (25 μg) daily for 3 months.
Maintenance
Vitamin D: 400 IU (10 μg) daily or 150 000 IU (3750 μg) at the start of autumn.‡
Monitoring
1 month: Serum calcium and alkaline phosphatase.
1-12 monthsVitamin D: 3000 IU (75 μg) daily for 3 months, or 300 000 IU (7500 μg) over 1–7 day
3 months: Serum calcium, magnesium, phosphate, alkaline phosphatase, calcidiol, parathyroid hormone. Wrist x-ray to assess healing of rickets.Annual: Calcidiol.
>12 monthsVitamin D: 5000 IU (125 μg) daily for 3 months, or 500 000 IU (15 000 μg) over 1–7 days.
Calcitriol , 1, 25 OH vitamin D, Calcidiol, 25 oh vitamin D
Adequate calcium intake
Age Calcium intake
0-6 months 210 mg
6-12 months 270 mg
1-3 years 300 mg
4-8 years 800 mg
9-18 years 1300 mg
Recent Studies on vitamin D in Jordanians
2011, Batieha Et al Ann Nutr Met– 37% females were deficient– 5.6% of males were deficient2010 Abdul Razzak , Pediatric International
28% deficient, 16% severeAssociation with breast feeding was found
National micronutrient survey 2010women deficient < 12 ng/ml > 50%
children 1-6 yrs< 11 ng/ml 10-20%Takruri et al , JMJ, 1-6 yrs also 30% insufficient
Study on newborn and pregnant mothers and vitamin D
• Ongoing study of vitamin D in newborn• More than 3000 vitamin D levels obtained in the
first day of life• Range from 0.1- 15 ng/ml • Cut off for this is 20 ng/ml• 99.8 were vitamin D deficient below 10• Mean was 3 !!!• 100 Mothers who were tested also had decreased
vitamin D level. Almost uniformly less than 10
Vitamin D levels in newborns in Jordan
Overwhelming majority >99% are deficient < 15 nanograms/ml
What should be done
• Increased sun exposure, not consistent with current social norms
• Supplementation of the different age groups• Fortification of food items, most useful• Which food item?? Oil preferable but flour more
feasible since it is cheaper and is the main staple food• For infants must give vitamin d drops• Pregnant women should be studied further and
supplementation during pregnancy must be done
Thank you