3 Dangers of Vitamin D deficiency: DOH February 2012 Up to ¼ of the population has low levels of Vitamin D in their bloodThe majority of pregnant women do not take Vitamin D supplementsPeople on lower income can get supplements through the Healthy Start Scheme
4 Vitamin DA prohormone essential for normal absorption of calcium from the gutIt occurs Naturally in the body following exposure to UVB sunlight, the body can also synthesize it (from cholesterol)A group of fat-soluble SecosteroidsIn humans, it can be ingested as cholecalciferol (vitamin D3) or ergocalciferol (vitamin D2)
5 25-hydroxy vitamin DThe 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 DIn the skin 7-dehydrocholseterol is converted to vitamin D3In 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 200124 cases of Vit D deficiency under 5 years of ageOverall incidence 7.5 per11/24 had bowed legs, presented at around 18 months6 had hypocalcemic seizures at 6 weeks of age4 had gross motor delay at 17.7 months of ageAll were black African or African-CaribbeanMajority were beastfed50% of those with convulsions were formula fed suggesting inadequate Vit D content in formula milkAdvised: need to supplement vulnerable groups including pregnant women
8 Vitamin D deficiency rickets among children in Canada Paediatricians surveyed between104 confirmed cases in the study periodOverall annual incidence 2.9 cases perMean age at diagnosis 1.4 yrs65% lived in urban areas89% had intermediate or darker skin94% were breastfedNone 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 2003Cases 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 womeninfants and young children under 5 years of ageolder people aged 65 years and overpeople 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 periodspeople who have darker skin, for example people of African, African-Caribbean and South Asian origin
11 Presentation Extremely variable and dependent on: ageSeverity of deficiencyUnderlying causesRanges from Biochemical to severe bony disease
12 Rickets in 1st year of life The most rapidly growing bones are : skull, upper limbs and ribsCraniotabesWidening on cranial suturesFrontal bossingEnlarged swollen epiphyses: particularly wristsBulging of costo-chondral joints (Rachitic Rosary)Harrison’s sulcusIrritabilityHypotonia
18 Severe Rickets In severe cases resulting from low Calcium: Tetany Laryngeal stridorParaesthesiaeConvulsionsRespiratory failure
19 Association of subclinical vitamin D deficiency with severe acute lower respiratory infection in childrenStudy of 150 hospitalized Indian children in 2004Subclinical 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 populationReduced synthesis from sun exposureGenetic:Vitamin D dependent rickets: ARHypophosphataemic Rickets: x-linked dominanyMalabsorption: Coeliac disease, Cystic FibrosisRenal disease (low 1,25 dihydroxy vitamin D- the most active form)Liver DiseaseMedications such as Anticonvulsants induce hepatic enzymes
21 Calciopenic: Low Ca Dietary calcium and vitamin D deficiency MalabsorptionLack of sun lightHepatic diseaseAnticonvulsant treatmentRenal disease1-α hydroxylase deficiencyEnd organ resistance to vitamin D
23 Biochemical Hypocalcaemia Hypophosphataemia Elevated Alkaline PhosphataseLow 1,25 – Dihydroxy vitamin DSerum Parathyroid Hormone level may be high
24 Radiologically Widening of growth plate Fraying, Cupping, and Widening of metaphysesPseudo fracturesSigns of secondary hyperparathyroidism : subperiosteal erosion
25 Other investigations Depending on underlying cause: Acidosis AminoaciduriaChronic renal failureanaemia
26 TreatmentCalcium, phosphate and vitamin D given in varying combinationsUnderlying abnormalities need to be treated (coeliac disease)Growth needs to be monitoredIn hypophsphataemic rickets large doses of Vitamin D are requiredIn 1α hydroxylase deficiency or end-organ resistance to vitamin D, 1,25- dihydroxy-cholecalciferol is usually required in significant dosesRegular renal USS is important
27 TreatmentVitamin D 1,000 to 5,000 μg IV/ day until normal alkaline phosphataseThen 10 μg / day and 500 ml/ day of milk for calcium requirementsExposure to sunlightDietary source: oily fish, fortified margarine
28 Dietary sources Oily fish Eggs Infant formula Some cereals, dairy products, low fat speads have a small amounts addedDifficult 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 DAll 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 pollutionLifestyles or cultural practices:decreased time spent outdoorsincrease the amount of body surface area covered by clothing when outdoors.individuals with darker skin pigmentationby 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 2012Providing advice on the prevention of vitamin D Deficiency in the at risk groupsand-factsheets/clinical/preventing-vitamin-d-deficiency- in-at-risk-groups/
34 NPA RecommendationsDaily vitamin D supplementation should be taken by:All pregnant and breastfeeding womenBreastfed infants from one month of age if mother did not take vit D supplements through pregnancyAll 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 overPeople who are not exposed to much sunPeople with darker skinsMedical conditions (GI, renal, liver)Medication (Carbamazepine, phenytoin, primidone, barbiturates, some anti-HIV medicines
35 NPA Supplementation guidance Patient ClassDaily supplementation dose of vitamin DPregnant or breastfeeding10 micrograms (440 iu)Breastfed infants from one month of age if mother did not take vitamin D supplementation during pregnancyBabies may need supplementation in the form of vitamin drops containing vitamin DChildren aged 6 mon to 5 yrs drinking 500 ml or more of formula milkNone requiredChildren 6 mon to 5 yrs NOT drinking 500 ml of formula milkVitamin drops containing vitamin DAged 65 years or all ages with limited exposure to sun10 micrograms (400 iu)
36 prognosis Excellent in most children Dependent on compliance with treatmentLess certain in hypophospahtaemic rickets and severe deformities of the limbs may result