detailed vitamin d synthesis and mechanism explained. pathophysiology of rickets explained. appropriate latest treatment guidelines given from uptodate. very nice given in uptodate and source from internate. ppt prepared by Dr sachin wagh junior resident in pediatrics MGM medical college & hospital aurangabad maharashtra

1. Rickets
Dr. Sachin Subhash Wagh
Dr Avinash Sangle Sir

2. Vitamin D
• Vitamin D can be synthesized in skin epithelial
cells from cholesterol
• Vitamin D is transported bound to vitamin D-
binding protein to liver where 25-hydroxylase
converts Vitamin D into 25-hydroxyvitamin D,
most abundant circulating form of Vitamin D.
• Final step in activation occurs in kidney, where
enzyme 1α -hydroxylase adds second hydroxyl
group, resulting 1,25-D.

3. Vitamin D binding protein25-hydroxylase
1α-Hydroxylase

4. • Most 1,25-D circulates bound to vitamin D-binding
protein.
• 1α-hydroxylase regulation
Up regulation
PTH
Hypophosphatemia
Down regulation
Hyperphosphatemia
1,25-D

5. • The following standards for defining vitamin
D status in healthy children and adolescents,
based on serum concentrations of 25OHD:
• ●Vitamin D sufficiency: 20 to 100 ng/mL (50
to 250 nmol/L)
• ●Vitamin D insufficiency: 12 to 20 ng/mL (30
to 50 nmol/L)
• ●Vitamin D deficiency:
<12 ng/mL (<30 nmol/L)

6. Functions of Vitamin D
Vitamin D
Intestine
Kidney Bone
 Bone Development
- Calcium absorption (small Intestine)
- Calcium Resorption ( Bone & Kidneys)
- Maintain blood calcium levels
- Phosphorus absorption
 Hormones
- Regulation of gene expression
- Cell Growth.

7. • Immunological function of vitamin D

8. Deficiency
 Rickets – disease of growing bone caused by
unmineralised matrix at growth plates in children only before
fusion of epiphysis.
 Osteomalcia - inadequet mineralization of bone in
children and adults.
 Osteoporosis- Proportionate loss of bone volume and
minerals

9. Rickets
Introduction
• Rickets is a condition that affects bone development in
children. It causes the bones to become soft and weak,
which can lead to bone deformities.
• Rickets in adults is known as osteomalacia or soft
bones.
• Rickets can cause bone pain, poor growth and
deformities of the skeleton, such as bowed legs,
curvature of the spine, and thickening of the ankles,
wrists and knees.
• Children with rickets are also more likely to fracture
their bones.

10. Rickets
 Causes
• Vitamin D Disorder
- Nutritional vitamin D deficiency
- Congenital vitamin D deficiency
- Secondary vitamin D deficiency
- Malabsorption
- Increased degradation
- Decreased liver 25-hydroxylase
- Vitamin D-dependent rickets types 1A and 2B
- Vitamin D-dependent rickets type 2A types 2B
- Chronic kidney disease

11. • Calcium deficiency
- Low intake
- Premature infants
- Malabsorption
- Primary disease
- Dietary inhibitors of calcium absorption
• Phosphorus deficiency
- Inadequate intake
- Premature infants
- Aluminum containing antacid

12. • Renal losses
- McCune-albright syndrome
- Fanconi syndrome
- X-linked hypophosphatemic rickets

13. Diagnostic approach

15. Causes of Rickets
Nutritional vitamin D deficicency
- Symptoms of hypocalcaemia
- Pneumonia, muscle weakness
- Increased PTH & hypophosphatemia
- Bicarbonate wasting
- Treatment:- Stoss therapy, Vitamin D (300000-
600000IU) orally or IM as 2-4 doses over 1 day. OR
- Vitamin D 2000IU/day for 3 months
- Prevention <1 year 400IU/day >1 year 600IU/day.

16. Vitamin D dependent Rickets Type-1
Type 1A Type 1B
• Mutation in gene encoding for 1α
hydroxylase, preventing
conversion of 25-D to 1,25-D
• Secondary to mutation in gene for
25 hydroxylase
• Normal level of 25-D but low levels
of 1,25-D
• Low level of 25-D but normal
level of 1,25-D
• Treatment – 1,25-D in a dose of
0.25-2μg/day.
• Targeting low normal calcium &
high normal PTH to avoid
hypercalciuria & nephrocalcinosis.
• Respond to pharmacological dose
of D2(3000U/Day).

17. Vitamin D-Dependent Rickets, Type-2
Type 2A Type 2B
• Mutation in gene encoding for
vitamin D receptor
• Result from overexpression of
hormone response element binding
protein that interfere action of
1,25-D .
• Level of 1,25-D increased
• Alopecia present • Alopecia present
• Treatment: high dose of vitamin
D2 with calcium supplement
Treatment: high dose of vitamin D2
with calcium supplement

18. Chronic kidney disease
- Decreased activity of 1α-hydroxylase
- Decreased level of 1,25-D associated with
Hyperphosphatemia as result of decreased
renal excretion.
- Treatment:- Vitamin D3 which causes
absorption of calcium, decreases level of PTH.
- Hyperphosphatemia is stimulus for PTH, low
phosphorus in diet and phosphate binder
adviced

19. Calcium deficiency
- Breast milk has sufficient calcium calcium
deficiency occurs when baby is on top feed or
after weaning.
- Rickets develops when dietary calcium low
typically
<200mg/day- <12 months old
<300mg/day- >12 months old
- Malabsorption of calcium may occure in celiac
disease and intestinal abetalipoproteninemia.

20. -Diagnosis:- increased ALP, increased PTH,
increased 1,25-D,
Calcium low or normal.
Serum phosphorus is low
Decreased urinary calcium & increased
phosphorus excretion.
-Treatment:- Adequate calcium diet
1-3 years – 700mg/day
4-8years – 1000mg/day
9-18 years – 1300mg/day.

21. Rickets of Prematurity
- Rickets in VLBW has become significant
problem as survival rate of VLBW increased
- Transfer of calcium & phosphorus from
mother to fetus occurs throughout pregnancy
but 80% occurs in 3rd trimester
- Rickets occurs after 1-4 months after birth can
have non traumatic fracture
- Respiratory distress from atelectasis & poor
ventilation
- Respiratory distress develops after >5 weeks
of birth

22. • Lab findings
- Serum phosphorus is low
- Normal 25-D level
- Hypophosphatemia stimulates renal 1α-
hydroxylase so 1,25-D level is high
- Serum calcium is high due to increased
absorption and bone dissolution
- Increased ALP
• Diagnosis:- screening test Sr.Ca, ALP, Sr.PO4

23. • Prevention:- provision of adequate amount of
calcium, phosphorus and vitamin D.
- Avoid Soy formula feed because decreased
bioavailability of calcium and phosphorus.
- 400 IU/day of Vit-D

24. Laboratory Findings in Various
Disorders Causing Rickets
Disorder Ca Pi PTH 25-
(OH)D
1,25-
(OH)2D
ALP Urine Ca Urine
Pi
Vitamin D deficiency N, N,
VDDR, Type 1A N, N
VDDR, Type 1B N, N
VDDR, Type 2A N, N
VDDR, Type 2B N, N
Dietary Ca deficiency N, N

25. Clinical features
• General
- Failure to thrive
- Protruding abdomen
- Muscle weakness
(proximal)
- Hypocalcemic
dilated
cardiomyopathy
- Increased
intracranial pressure

26. • Head
- Craniotabes
- Frontal bossing
- Delayed fontanel
closure
- Delayed dentition
- Caries
- Craniosynostosis
• Chest
- Rachiatic rosary
- Harrison grove
- Respiratory
atelectasis and
infection

27. • Back
- Scoliosis
- Kyphosis
- Lordosis
• Extremities
- Enlargement of wrist and
ankles
- Valgus or varus deformity
- Windswept deformity
- Anterior bowing of tibia &
femur
- Coxa vara

28. Radiographic features

29. Message to parents

30. THANK YOU