Nutritional Rickets

Dr. Siddharth GuptaSenior resident

Chacha Nehru Bal Chikitsalya, Delhi

THE JOURNAL CLUB

Definition

Nutritional rickets

Disorder of defective chondrocyte differentiation and mineralization of

the growth plate and defective osteoid mineralization

Osteomalacia

Osteomalacia is abnormal matrix mineralization in established bone, and

although present in children with rickets, it is used to describe bone

mineralization defects after completion of growth

CALCIUM VITAMIN D

Diagnosis

• The diagnosis of Nutritional rickets is

made on the basis of :

• History

• Physical examination

• Biochemical testing

• Confirmed by radiographs

LAB/BIOCHEMICAL

• Biochemical testing alone is not sufficient to diagnose NR

and may not differentiate whether the primary cause of NR

• Combined deficiencies are common

• Dietary history

Increasing vs Decreasing

• Serum PTH

• Alkaline phosphatase (ALP)

• Urinary phosphorus levels

• 25-hydroxyvitamin D

(25OHD)

• Serum phosphorus

• Serum calcium

• Urinary calcium

How to assess serum Vit D? Vitamin D status is assessed by measuring blood

levels of total 25OHD which has been classified by the panel as follows:

0 20 40 60

Sufficient(>50)

Insufficient(30-50)

Deficient(<30)

25OHD(nmol/L)

Vit d(nmol/L)

In healthy children, routine 25OHD screening is not recommended

Why 25OHD?

NR does not include rickets associated with heritable disorders

of vitamin D metabolism, including 1-α-hydroxylase

deficiency and vitamin D receptor defects, or congenital or

acquired hypophosphatemic rickets

Symptomatic Deficiency

• NR may not occur with very low 25OHD concentrations but is

more likely to occur with deficiency sustained over time, i.e.

chronic deficiency--------Duration is important

• Most children with vitamin D deficiency are asymptomatic

Reason CALCIUM VITAMIN D

Recommendations • 25OHD level at 30–34 nmol/l is the critical

cutoff below which NR is more likely to occur• PTH starts increasing when 25OHD levels

drop below 34 nmol/l• Seasonal variations in 25OHD

maintaining 25OHD levels >50 nmol/l (i.e. sufficient)

Dietary Calcium Intake to Prevent Rickets

AGE (Months) DOSE (Mg/ day)

<6 200

6-12 260

>12 Atleast 300

Sufficient >500

Insufficient 300-500

Deficient <300

“For children over 12 months of age, dietary calcium intake of <300 mg/d increases the risk of rickets independent of serum 25OHD levels”

Vitamin D Deficiency and Fractures

• Children with radiographically confirmed rickets have an increased risk of fracture

• Children with simple vitamin D deficiency are not at an increased risk of fracture.

Prevention and Treatment of Nutritional Rickets and Osteomalacia-Vitamin D Supplementation

AGE (Months) DOSE (IU/DAY)

<12 400

>12 600

Infants and toddlers with 25OHD < 50nmol/L

50-100 000 every 3 months

“Among infants and toddlers with 25OHD levels < 50 nmol/L for whom daily vitamin D supplementation may not be ideal, intermittent bolus doses of 50 to 100 000 IU every 3 months hold promise”

How to prevent risk factors?

Candidates for vitamin D supplementation

• Children with a history of symptomatic vitamin D deficiency

requiring treatment

• Children and adults at high risk of vitamin D deficiency with

factors or conditions that reduce synthesis or intake of

vitamin D

• Pregnant women

Dose of Vitamin D and Calcium for the Treatment of Nutritional Rickets

• The minimal recommended dose of vitamin D is 2,000 IU/day

(50 μg) for a minimum of 3 months

• Oral calcium, 500 mg/day, either as dietary intake or

supplements, should be routinely used in conjunction with

vitamin D in the treatment regardless of age or weight

“ Combined treatment is justified because studies have shown that the diet of children and adolescents with NR is generally

low in both vitamin D and calcium”

CONCLUSION OF GLOBAL CONSENSUS

Difference in opinions regarding dosage of vitamin D

• The UK guidelines

• The US guidelines

• Saggese G et al Vitamin D in childhood and adolescence: an expert position statement. Eur J Pediatr. 2015 May;174(5):565-76. doi: 10.1007/s00431-015-2524-6. Epub 2015 Apr 2.

AGE DOSE (IU/DAY)

< 6 Months 3000 For 8-12 weeks daily

6 months -12 years 6000 for 8-12 weeks daily

12-18 years 10000 for 8-12 weeks daily

AGE DOSE (IU)

>12 months 5000 dailly for 8-12 weeks

>1 month 1lac – 6 lac IU single dose

Teenagers 50000 weekly for 8 weeks

What we follow IAP

Vitamin D Deficiency in Childhood – A Review of Current Guidelines on Diagnosis and Management

S Balasubramanian, K Dhanalakshmi and Sumanth AmperayaniFrom Kanchi Kamakoti CHILDS Trust Hospital, The CHILDS Trust Medical Research Foundation, 12-A, Nageswara Road,

Nungambakkam, Chennai 600 034, Tamil Nadu, India

THE STOSS REGIMEN

The Stoss therapy

• The administration of a large dose given as a single dose or in

divided doses over several days

• This approach has been advocated for ease of use and

compliance • 3lac – 6lac IU as a single dose

• Risk of hypercalcemia

• Hence should be limited to children who have evidence of

symptomatic vitamin D deficiency

What is the end point of treatment?

Endpoint of an ALP level < 350 U/L and radiographic evidence

of near-complete healing of rickets was seen in a higher

percentage of patients who received a combination of calcium

and vitamin D (58%) or calcium alone (61%) than in those who

received vitamin D alone (19%)

Thacher TD, Fischer PR, Pettifor JM, et al. A comparison of calcium, vitamin D, or both for nutritional rickets in Nigerian children. N

Engl J Med. 1999;341(8):563–568

ORAL OR INTRAMUSCULAR• Oral treatment: restores 25OHD levels faster than

intramuscular (IM) treatment

• For daily treatment, both D 2 and D 3 are equally effective

• When single large doses are used, D 3 appears to be

preferable compared to D 2 because the former has a longer

half-life

• Duration : minimum of 12 weeks, recognizing that some

children may require a longer treatment duration

Vitamin D synthesis(Mankin part 1)

Different brandname and their composition

Alfacalcidol (or 1hydroxycholecalciferol)

The sunlight

• No exact studies done yet as it is multifactorial

• UVB (290-315 nm) is preferable

• The more oblique rays are absorbed by ozone so less role

before 10 am and after 3 pm“A healthy adult in a bathing suit exposed to

an amount of sunlight that causes a minimal erythema (lightpinkness to the skin 24 h after exposure; 1 MED) is equivalent

to ingesting approximately 20,000 IU of vitamin D”

Factors affecting solar vitamin D

• Latitude• Pigmentation• Age• Use of sunscreen SPF 30• Glass• Time of day

Prevention of Osteomalacia During Pregnancy and Lactation and Congenital

Rickets• Pregnant women should receive 600 IU/d of supplemental

vitamin D

• Pregnant women do not need calcium intakes above

recommended nonpregnant intakes to improve neonatal bone

• Advantages of taking supplementation during pregnancy: 1.Prevention from large fontenelle 2.Avoids neonatal hypocalcemia 3.Prevention from congenital rickets 4.Improve dental enamel formation

• Maternal calcium intake during pregnancy or lactation is not

associated with breast milk calcium concentrations

• Lactating women should not take high amounts of vitamin D

as a means of supplementing their infant

• Lactating women should ensure they meet the dietary

recommendations for vitamin D (600 IU/d)

Influence of calcium or vitamin D supplementation in pregnancy or lactation on breast milk calcium or vitamin D