Rickets is caused by vitamin D deficiency which leads to low calcium and phosphate levels. This weakens the bones and causes skeletal deformities. Vitamin D is obtained from sunlight exposure and diet. Lack of sunlight, inadequate diet, dark skin pigmentation, liver or kidney problems can cause vitamin D deficiency and subsequent rickets. Symptoms include bowed legs, soft skull bones, spinal curvature and bone pain. Diagnosis involves blood tests showing low calcium, vitamin D and high alkaline phosphatase levels along with characteristic bone changes on x-ray. Treatment is vitamin D supplementation and ensuring adequate calcium and vitamin D in the diet.

2. Rickets is a childhood disorder
involving softening and weakening
of the bones.
It is primarily caused by lack of
vitamin D, calcium, or phosphate.

3. Vitamin D is a fat-soluble vitamin that may be absorbed from the
intestines or may be produced by the skin when the skin is
exposed to sunlight (ultraviolet light of sunlight helps the body
to form vitamin D).
The absorbed vitamin D is converted into its active form to act as a
hormone to regulate calcium absorption from the intestine and
to regulate levels of calcium and phosphate in the bones.
If there is a deficiency of Vitamin D, the body is unable to properly
regulate calcium and phosphate levels. When the blood levels of
these minerals become too low, it results in destruction of the
support matrix of the bones.

4. Sunlight as a source of vitamin D
Lack of vitamin D production by the skin may occur if a
person is confined indoors, or works indoors during the
daylight hours, or lives in climates with little exposure to
sunlight.
Sunlight is important to skin
production of
vitamin D and
environmental conditions
where sunlight exposure is
limited may reduce this
source of vitamin D.

5. Sunlight as a source of vitamin D
Adequate supplies of vitamin
D3 can be synthesized with
sufficient exposure to solar
ultraviolet B radiation
Melanin, clothing or
sunscreens that absorb UVB
will reduce cutaneous
production of vitamin D3

6. Rickets
In rickets, another mechanism in the body works to increase the blood
calcium level. The parathyroid gland may increase its functioning rate
to compensate for decreased levels of calcium in the bloodstream.
To increase the level of calcium in the blood the hormone destroys the
calcium present in the bones of the body and this results in further loss
of calcium and phosphorous from the bones. In severe cases, cysts may
develop in the bones.
Vitamin D deficiency could be caused due to numerous reasons

7.  What are the causes for deficiency of Vitamin D?

8.  Environmental conditions where sunlight exposure is
limited like indoor confinement or working indoors during
daylight hours may reduce source of vitamin D;
 Inadequate daily consumption - a lack of vitamin D in the
diet, a dietary lack of calcium and phosphorous may also
play a part in nutritional causes of rickets, have trouble
digesting milk products, people who are lactose intolerant;
 Liver Failure;
 Dark Pigmentation

9.  Problem of malabsorption called steatorrhea, in which the
body is unable to absorb fats, and they are passed directly
out the body in the stool. The result of this problem is that
Vitamin D, which is usually absorbed with fat, and calcium
are poorly absorbed. This poor absorption can be a result of
digestive disorders. Steatorrhea could also lead to other
deficiencies.
 Kidney Failure (congenital or acquired kidney disorders) -
due to tubular acidosis in which there is an increased
amount of acid in the body;

10. 1. Lack of sunshine due to:
 1) Lack of outdoor activities
 2) Lack of ultraviolet light in fall and winter
 3) Too much cloud, dust, vapour and smoke

11. 2. Improper feeding:
1) Inadequate intake of Vitamin D
 Breast milk 0-10IU/100ml
 Cow’s milk 0.3-4IU/100ml
 Egg yolk 25IU/average yolk
 Herring 1500IU/100g
2) Improper Ca and P ratio

12. 3. Fast growth, increased requirement (relative deficiency)
4. Diseases and drug:
 Liver diseases, renal diseases
 Gastrointestinal diseases
 Antiepileptic
 Glucocorticosteroid

13. Cholecalciferol (vitamin D-3) is formed in the skin from
7-dihydrotachysterol. This steroid undergoes hydroxylation in 2 steps.
Pathophysiology - Metabolism of vitamin D
• The first hydroxylation occurs at position 25 in the liver, producing
calcidiol (25-hydroxycholecalciferol), which circulates in the plasma as
the most abundant of the vitamin D metabolites and is thought to be a
good indicator of overall vitamin D status.

14.  Cholecalciferol (vitamin D-3) is formed in the skin from
7-dihydrotachysterol. This steroid undergoes hydroxylation in 2 steps.
Pathophysiology
• The second hydroxylation step occurs in the kidney at the 1 position, where it
undergoes hydroxylation to the active metabolite calcitriol (1,25-
dihydroxycholecalciferol - DHC). This cholecalciferol is not a vitamin, but a
hormone.

15.  Not always essential
 Body can make it if
exposed to enough
sunlight
 Made from cholesterol in
the skin

17. Calcitriol acts on regulation of
calcium metabolism:
 Calcitriol promotes absorption of calcium and
phosphorus from the intestine,
 increases reabsorption of phosphate in the kidney,
 acts on bone to release calcium and phosphate;
 Calcitriol may also directly facilitate calcification.
Calcitriol (1,25-DHC) – acts as a hormone rather than a vitamin,

18. • These actions increase the concentrations of calcium and
phosphorus in extracellular fluid.
• The increase of Ca and P
in extracellular fluid, in
turn, leads to the
calcification of osteoid,
primarily at the
metaphyseal growing ends
of bones but also
throughout all osteoid in
the skeleton.
• Parathyroid hormone
facilitates the 1-hydro-
xylation step in vitamin D
metabolism

19.  Vitamin D deficiency
 Absorption of Ca, P
 Serum Ca


20. PTH
High secretion
P in urine Decalcification of old bone
P in blood Ca in blood normal or low slightly
Ca, P product
Rickets

21.  Low secretion of PTH
 Failure of decalcification of bone
 Low serum Ca level
 Rachitic tetany
(Spasmophylia)

22.  In the vitamin D deficiency state,
hypocalciemia develops, which
stimulates excess parathyroid
hormone, which stimulates renal
phosphorus loss, further reducing
deposition of calcium in the bone.
 Excess parathyroid hormone also
produces changes in the bone similar
to those occurring in
hyperparathyroidism.

23.  Early in the course of rickets, the
calcium concentration in the serum
decreases.
 After the parathyroid response, the
calcium concentration usually returns
to the reference range, though
phosphorus levels remain low.

24. The history in patients with rickets may include the following:
 The infant's gestational age, diet and degree of sunlight
exposure should be noted.
 A detailed dietary history should include specifics of
vitamin D and calcium intake.
 A family history of short stature, orthopedic
abnormalities, poor dentition, alopecia, parental
consanguinity may signify inherited rickets.
Evaluation

25. Rickets is a systematic disease with skeletons
involved most, but the nervous system, muscular
system and other system are also involved.

26.  Generalized muscular hypotonia is observed in the most patients
with clinical signs of rickets.
 Craniotabes manifests early in infants, although this feature may
be normal in infants, especially for those born prematurely.
Clinical signs
• If rickets occurs at a later age,
thickening of the skull
develops. This produces frontal
bossing and delays the closure
of the anterior fontanelle.

27. Protruding forehead
asymmetrical or odd-shaped skull

28. • Skeletal
deformities
including Bow legs,
Forward projection of the
breastbone - pigeon chest
or pectus carinatum),
Funnel chest
(pectus excavatum),
"Bumps" in the rib cage
(rachitic rosary) and
asymmetrical or odd-
shaped skull;

29. Chest deformity
Funnel chest – pectus excavatum
Pigeon chest

30. Clinical signs
 In the chest, knobby
deformities results in the
rachitic rosary along the
costochondral junctions.
 The weakened ribs pulled
by muscles also produce
flaring over the diaphragm,
which is known as Harrison
groove.
 The sternum may be pulled
into a pigeon-breast deformity.
Rib beading
(rachitic rosary)

32. Bowlegs and knock-
knees.
Clinical signs

33. Knock knee deformity
(genu valgum)
Bowleg deformity
(genu varum)

34. Bowlegs and knock-knees
Pelvic deformities

35.  The ends of the long bones demonstrate that same knobby
thickening. At the ankle, palpation of the tibial
Clinical signs
malleolus gives
the impression of
a double
epiphysis
(Marfan sign).

36. Clinical signs
 Increased tendency toward
bone fractures. Because the
softened long bones may bend,
they may fracture one side of
the cortex (greenstick fracture).

37.  Spine deformities
(spine curves abnormally,
including scoliosis or
kyphosis).
 In more severe instances in
children older than 2 years,
vertebral softening leads to
kyphoscoliosis
Clinical signs

38.  Pain in the bones of Arms, Legs, Spine, Pelvis.
 Dental deformities
 Delayed formation of teeth
 Defects in the structure of teeth
 Holes in the enamel
 Increased incidence of cavities in the teeth (dental caries)
Clinical signs

39. Progressive weakness
Decreased muscle tone (loss of muscle strength)
Muscle cramps
Impaired growth
Short stature (adults less than 5 feet tall)
Fever or restlessness, especially at night
Clinical signs

40. Bowlegs and knock-knees
Short stature

41. Gait disturbances and
neurologic abnormalities
(such as hyperreflexia) in all
children should be sought.
The review of systems should
focus on growth and
orthopedic concerns and signs
and symptoms of
hypocalcemia, such as muscle
cramps, numbness,
paresthesias, tetany and
seizures.

42. Laboratory findings
Laboratory investigation may include:
 serum levels of calcium (total and ionized with
serum albumin),
 phosphorus,
 alkaline phosphatase (ALP)
 parathyroid hormone,
 calcidiol
 urine studies include urinalysis and levels of
urinary calcium and phosphorus.

43. Decreases
in serum calcium, serum
phosphorus, calcidiol,
calcitriol, urinary calcium.
The most common laboratory findings in
nutritional rickets are:
Parathyroid hormone,
alkaline phosphatase,
urinary phosphorus
levels are elevated.

44.  Early on in the course of rickets, the calcium (ionized fraction) is low;
however it is often within the reference range at the time of diagnosis as
parathyroid hormone levels increase.
 Calcidiol (25-hydroxy vitamin D) levels are low, and parathyroid
hormone levels are elevated; however, determining calcidiol and
parathyroid hormone levels is typically not necessary.
 Calcitriol levels may be normal or elevated because of increased
parathyroid activity.
 The phosphorus level is invariably low for age.
 Alkaline phospohatase levels are elevated.
 A generalized aminoaciduria occurs from the parathyroid activity;
aminoaciduria does not occur in familial hypophosphatemia rickets
(FHR).
Laboratory Studies

45.  Classic radiographic findings include:
widening of the distal epyphysis, fraying and
widening of the metaphysis, and angular
deformities of the arm and leg bones.

46. Classic radiographic findings include
Anteroposterior and lateral radiographs of the wrist of an 8-year-old boy
with rickets demonstrates cupping and fraying of the metaphyseal region

47.  Classic radiographic findings include:
Radiographs of the knee of a 3-year-old girl with hypophosphatemia
depict severe fraying of the metaphysis.

48. Rickets in wrist - uncalcified lower ends of bones are
porous, ragged, and saucer-shaped
(A) Rickets in 3 month old infant
(B) Healing after 28 days of
treatment
(C) After 41 days of treatment
A
B C

49. Radiographic image of wrist and
forearm showing pathologic
fractures of radius and ulna with
rachitic changes of distal end of
radius and ulna.

50. X-ray in rickets

52.  I Mild form: small changes of nervous system,
changes of one part of the skeleton;
 II Moderate form: changes of all organs and systems,
changes of two parts of the skeleton;
 III Severe form: damaging function of all organs and
systems, changes of three parts of the skeleton;
Classification

53. Types of Rickets
Nutritional
Nutritional rickets results from inadequate sunlight
exposure or inadequate intake of dietary vitamin
D, calcium, or phosphorus.

54. Vitamin D dependent
 Vitamin D-dependent rickets, type I is secondary to a
defect in the gene that codes for the production of renal
25(OH)D3-1-alpha-hydroxylase.
 Vitamin D-dependent rickets, type II is a rare autosomal
disorder caused by mutations in the vitamin D receptor.
Type II does not respond to vitamin D treatment; elevated
levels of circulating calcitriol differentiate this type from
type I.

55. Vitamin D resistant
 Rickets refractory to vitamin D treatment may be caused
by the most common heritable form, known as vitamin D-
resistant rickets or familial hypophosphatemic rickets.
 Because of mutations of the phosphate-regulating gene on
the X chromosome, renal wasting of phosphorus at the
proximal tubule level results in hypophosphatemia.
Normal levels of calcitriol are found in this disorder.

56. Other Conditions That Can Cause Rickets
 Medications
 Antacids
 Anticonvulsants
 Corticosteroids
 Loop diuretics
 Malignancy
 Prematurity
 Diseases of organs associated with vitamin D and calcium
metabolism
 Kidney disease
 Liver and biliary tract disease
 Malabsorption syndromes
 Celiac disease
 Cystic fibrosis (rare)

57.  Assessed according to the followings:
 1. History
 2. Physical examination
 3. Laboratory findings
 4. Roentgen-graphic changes

58.  The replacement of Vitamin D may correct rickets using these
methods of ultraviolet light and medicine. Rickets heals
promptly with 4000 IU of oral vitamin D per day administered
for approximately one month.
 Parents are instructed to take their infants outdoors for
approximately 20 minutes per day with their faces exposed.
Children should also be encouraged to play outside.
 Foods that are good sources of vitamin D include cod liver oil,
egg yolks, butter and oily fish. Some foods, including milk and
breakfast cereals, are also fortified with synthetic vitamin D.

59. 1. Special therapy: Vitamin D therapy
 A. General method: Vitamin D 2000-4000 IU/day
for 2-4 weeks, then change to
preventive dosage – 400 IU.
 B. A single large dose: For severe case, or Rickets with
complication, or those who can’t bear oral therapy.
Vitamin D3 200000 – 300000 IU, im,
preventive dosage will be used after 2-3 months.

60. 4. Calcium supplementation: Dosage: 1-3 g/day
 only used for special cases, such as baby fed mainly
with cereal or infants under 3 months of age and
those who have already developed tetany.
5. Surgery:
In children with bone deformities after 4 years old
plastic surgery may be useful.

61. 1. Pay much attention to the health care of pregnant
and lactating women, instruct them to take adequate
amount of vitamin D.
2. Advocate sunbathing
3. Advocate breast feeding, give supplementary food on
time

62. Vitamin D supplements
 Because of human milk contains only a small amount of
vitamin D, the American Academy of Pediatrics (AAP)
recommends that all breast-fed infants receive 400 IU of oral
vitamin D daily beginning during the first two months of life
and continuing until the daily consumption of vitamin D-
fortified formula or milk is two to three glasses, or 500 mL.
 AAP also recommends that all children and adolescents
should receive 400 IU a day of vitamin D.