1. Vitamin D deficiency in children
Dr. Rim El-Rifai
Consultant Paediatrician
Queen Mary’s Hospital for Children

3. Dangers of Vitamin D deficiency: DOH February 2012
Up to ¼ of the population has low levels of Vitamin D in their blood
The majority of pregnant women do not take Vitamin D supplements
People on lower income can get supplements through the Healthy Start Scheme

4. Vitamin D
A prohormone essential for normal absorption of calcium from the gut
It occurs Naturally in the body following exposure to UVB sunlight, the body can also synthesize it (from cholesterol)
A group of fat-soluble Secosteroids
In humans, it can be ingested as cholecalciferol (vitamin D3) or ergocalciferol (vitamin D2)

5. 25-hydroxy vitamin D
The 25-hydroxy vitamin D test is the most accurate way to measure vitamin D level.
In the kidney, 25-hydroxy vitamin D changes into an active form of the vitamin.

6. Synthesis of Vitamin D
In the skin 7-dehydrocholseterol is converted to vitamin D3
In the liver vitamin D is converted to 25- hydroxycholecalciferol, or 25-hydroxyvitamin D (Calcidiol) —abbreviated 25(OH)D: the specific vitamin D metabolite measured in serum to determine a vitamin D status.
Part of the calcidiol is converted by the kidneys to 1, 25- dihydroxy vitamin D3 (Calcitriol), the biologically active form of vitamin D.
Calcitriol circulates in the blood, regulating the concentration of Calcium and Phosphate in the bloodstream and promoting the healthy growth and remodeling of bone.
Calcidiol is also converted to calcitriol outside of the kidneys for other purposes, such as the proliferation, differentiation and apoptosis of cells;
calcitriol also affects neuromuscular function and inflammation.[

7. Vitamin D deficiency in Children in the UK ADCH 2007
Survey of Paediatricians in the West Midlands in 2001
24 cases of Vit D deficiency under 5 years of age
Overall incidence 7.5 per
11/24 had bowed legs, presented at around 18 months
6 had hypocalcemic seizures at 6 weeks of age
4 had gross motor delay at 17.7 months of age
All were black African or African-Caribbean
Majority were beastfed
50% of those with convulsions were formula fed suggesting inadequate Vit D content in formula milk
Advised: need to supplement vulnerable groups including pregnant women

8. Vitamin D deficiency rickets among children in Canada
Paediatricians surveyed between
104 confirmed cases in the study period
Overall annual incidence 2.9 cases per
Mean age at diagnosis 1.4 yrs
65% lived in urban areas
89% had intermediate or darker skin
94% were breastfed
None of the breast fed babies had received a supplement according to guidelines (400 IU/day)
Maternal risk factors included: limited sun exposure, lack of Vit D from diet, lack of Vitamin supplementation during pregnancy and lactation

9. AMERICAN ACADEMY OF PEDIATRICS Prevention of Rickets and Vitamin D Deficiency: New Guidelines for Vitamin D Intake, April 2003
Cases of rickets in infants attributable to inadequate vitamin D intake and decreased exposure to sunlight continue to be reported in the United States.
A state of deficiency occurs months before rickets is obvious on physical examination.
Also, it is acknowledged that most vitamin D in older children and adolescents is supplied by sunlight exposure. However, dermatologists and cancer experts advise caution in exposure to sun, especially in childhood, and recommend regular use of sunscreens.
Sunscreens markedly decrease vitamin D production in the skin.

10. People at risk of Vit D deficiency
all pregnant and breastfeeding women, especially teenagers and young women
infants and young children under 5 years of age
older people aged 65 years and over
people who have low or no exposure to the sun, for example those who cover their skin for cultural reasons, who are housebound or confined indoors for long periods
people who have darker skin, for example people of African, African-Caribbean and South Asian origin

11. Presentation Extremely variable and dependent on:
age
Severity of deficiency
Underlying causes
Ranges from Biochemical to severe bony disease

12. Rickets in 1st year of life
The most rapidly growing bones are : skull, upper limbs and ribs
Craniotabes
Widening on cranial sutures
Frontal bossing
Enlarged swollen epiphyses: particularly wrists
Bulging of costo-chondral joints (Rachitic Rosary)
Harrison’s sulcus
Irritability
Hypotonia

13. Bowing of legs
Frontal bossing

14. Rachitic Rosary

15. Enlarged Swollen Epiphyses

16. Rickets after the first year
Genu Varum, Genu Valgum
Abnormal dentition with enamel hypoplasia
Bone pain
Proxymal myopathy

17. Genu Valgum and Genu Varum

18. Severe Rickets In severe cases resulting from low Calcium: Tetany
Laryngeal stridor
Paraesthesiae
Convulsions
Respiratory failure

19. Association of subclinical vitamin D deficiency with severe acute lower respiratory infection in children
Study of 150 hospitalized Indian children in 2004
Subclinical vitamin D deficiency and non-exclusive breast feeding in the first 4 months of age:
significant risk factors for severe acute lower respiratory infections in Indian children

20. Causes of Vitamin D deficiency
Poor dietary intake most common in Asian population
Reduced synthesis from sun exposure
Genetic:
Vitamin D dependent rickets: AR
Hypophosphataemic Rickets: x-linked dominany
Malabsorption: Coeliac disease, Cystic Fibrosis
Renal disease (low 1,25 dihydroxy vitamin D- the most active form)
Liver Disease
Medications such as Anticonvulsants induce hepatic enzymes

21. Calciopenic: Low Ca Dietary calcium and vitamin D deficiency
Malabsorption
Lack of sun light
Hepatic disease
Anticonvulsant treatment
Renal disease
1-α hydroxylase deficiency
End organ resistance to vitamin D

22. Phosphopenic:low PO4 Fanconi Syndrome
X-linked hypoposphataemic rickets
Renal tubular acidosis
Ocul-cerebro-renal syndrome (Lowe syndrome)
Osteopenia of prematurity

23. Biochemical Hypocalcaemia Hypophosphataemia
Elevated Alkaline Phosphatase
Low 1,25 – Dihydroxy vitamin D
Serum Parathyroid Hormone level may be high

24. Radiologically Widening of growth plate
Fraying, Cupping, and Widening of metaphyses
Pseudo fractures
Signs of secondary hyperparathyroidism : subperiosteal erosion

25. Other investigations Depending on underlying cause: Acidosis
Aminoaciduria
Chronic renal failure
anaemia

26. Treatment
Calcium, phosphate and vitamin D given in varying combinations
Underlying abnormalities need to be treated (coeliac disease)
Growth needs to be monitored
In hypophsphataemic rickets large doses of Vitamin D are required
In 1α hydroxylase deficiency or end-organ resistance to vitamin D, 1,25- dihydroxy-cholecalciferol is usually required in significant doses
Regular renal USS is important

27. Treatment
Vitamin D 1,000 to 5,000 μg IV/ day until normal alkaline phosphatase
Then 10 μg / day and 500 ml/ day of milk for calcium requirements
Exposure to sunlight
Dietary source: oily fish, fortified margarine

28. Dietary sources Oily fish Eggs Infant formula
Some cereals, dairy products, low fat speads have a small amounts added
Difficult to get sufficient Vitamin D from diet alone

29. Breast feeding and Vitamin D
Infants who are breastfed but do not receive supplemental vitamin D or adequate sunlight exposure are at increased risk of developing vitamin D deficiency or rickets.
Human milk typically contains a vitamin D concentration of 25 IU/L or less.
The recommended adequate intake of vitamin D cannot be met with human milk as the sole source of vitamin D for the breastfeeding infant.

30. Formulas and Vitamin D
All infant formulas must have a minimum vitamin D concentration of 40 IU/100 kcal (258 IU/L of a 20- kcal/oz formula) and a maximum vitamin D concentration of 100 IU/100 kcal (666 IU/L of a 20- kcal/oz formula).
All formulas sold have at least 400 IU/L.
If an infant is ingesting at least 500 mL per day of formula (vitamin D concentration of 400 IU/L), he or she will receive the recommended vitamin D intake of 200 IU per day.

31. Sunlight Exposure Decreased sunlight exposure occurs: Skin Cancer:
during the winter and other seasons and when sunlight is attenuated by clouds,
air pollution
Lifestyles or cultural practices:
decreased time spent outdoors
increase the amount of body surface area covered by clothing when outdoors.
individuals with darker skin pigmentation
by the use of sunscreens.
Skin Cancer:
age at which direct sunlight exposure is initiated is more important than the total sunlight exposure over a lifetime in determining the risk of skin cancer.
AAP guidelines for decreasing exposure:
infants younger than 6 months should be kept out of direct sunlight,
children’s activities that minimize sunlight exposure should be selected,
protective clothing as well as sunscreens should be used.

32. Chief Medical Officers:
“A significant proportion of people in the UK probably have inadequate levels of vitamin D in their blood.
“People at risk of vitamin D deficiency, including pregnant women and children under 5, are already advised to take daily supplements”.
DOH February 2012

33. National Pharmacy Association
Fact sheet prepared with assistance of DOH in March 2012
Providing advice on the prevention of vitamin D Deficiency in the at risk groups
and-factsheets/clinical/preventing-vitamin-d-deficiency- in-at-risk-groups/

34. NPA Recommendations
Daily vitamin D supplementation should be taken by:
All pregnant and breastfeeding women
Breastfed infants from one month of age if mother did not take vit D supplements through pregnancy
All children aged 6 mon- 5 years (except who receive more than 500 ml of formula milk, which is fortified with Vit D)
People aged 65 and over
People who are not exposed to much sun
People with darker skins
Medical conditions (GI, renal, liver)
Medication (Carbamazepine, phenytoin, primidone, barbiturates, some anti-HIV medicines

35. NPA Supplementation guidance
Patient Class
Daily supplementation dose of vitamin D
Pregnant or breastfeeding
10 micrograms (440 iu)
Breastfed infants from one month of age if mother did not take vitamin D supplementation during pregnancy
Babies may need supplementation in the form of vitamin drops containing vitamin D
Children aged 6 mon to 5 yrs drinking 500 ml or more of formula milk
None required
Children 6 mon to 5 yrs NOT drinking 500 ml of formula milk
Vitamin drops containing vitamin D
Aged 65 years or all ages with limited exposure to sun
10 micrograms (400 iu)

36. prognosis Excellent in most children
Dependent on compliance with treatment
Less certain in hypophospahtaemic rickets and severe deformities of the limbs may result