For study

2. Vitamin D metabolism

3.  Normal bone growth & mineralization require adequate
availability of calcium & phosphate.
 Deficient mineralization can result in rickets and/or
osteomalacia.
 Rickets refers to the changes caused by deficient
mineralization at the growth plate.
 Rickets usually occur together as long as the growth plates
are open.

4.  Vitamin D disorders
◦ Nutritional vitamin D deficiency; Congenital vitamin D deficiency;
Secondary vitamin D deficiency; Malabsorption ; Increased
degradation; Decreased liver 25-hydroxylase; Vitamin D-dependent
rickets type 1; Vitamin D-dependent rickets type 2; Chronic renal
failure.

5.  Calcium deficiency
◦ Low intake, Calcium deficient Diet, Premature infants (rickets of
prematurity), Malabsorption, Dietary inhibitors of calcium
absorption
 Phosphorus deficiency
◦ Inadequate intake, Premature infants (rickets of
prematurity), Aluminum-containing antacids

6.  RENAL LOSSES
◦ X-linked hypophosphatemic rickets; Autosomal dominant
hypophosphatemic rickets; Hereditary hypophosphatemic rickets
with hypercalciuria; Overproduction of phosphatonin (Tumor-
induced rickets, McCune-Albright syndrome, Epidermal nevus
syndrome, Neurofibromatosis), Fanconi syndrome, Dent disease
 DISTAL RENAL TUBULAR ACIDOSIS

7.  GENERAL Failure to thrive; Listlessness; Protuding abdomen; Muscle
weakness (especially proximal); Fractures.
 HEAD Craniotabes; Frontal bossing; Delayed fontanelle closure; Delayed
dentition; caries; Craniosynostosis
 CHEST Rachitic rosary; Harrison groove; Respiratory infections and atelectasis
 BACK Scoliosis ,Kyphosis ,Lordosis
 EXTREMITIES Enlargement of wrists and ankles; Valgus or varus deformities
Windswept deformity (combination of valgus deformity of 1 leg with varus
deformity of the other leg); Anterior bowing of the tibia and femur; Coxa
vara; Leg pain.
 HYPOCALCEMIC SYMPTOMS Tetany ; Seizures; Stridor due to laryngeal spasm

8.  Extraskeletal manifestation of rickets vary depending upon
the mineral deficiency.
 Hypoplasia of the dental enamel is typical for hypocalcemic
rickets, whereas abscesses of the teeth occur more often in
phosphopenic rickets.
 Hypocalcemic seizures, decreased muscle tone leading to
delayed motor milestones, recurrent infections, increased
sweating.

15. Diagnostic approach to suspected rickets

16. Diagnostic approach to hypocalcimic rickets

17. Diagnostic approach to hypophosphatemic rickets

18. Biochemical findings in rickets

19.  Alkaline phosphatase usually is ↑in all forms of rickets.
 Serum phosphorus concentrations usually are↓ in both
hypocalcemic and hypophosphatemic rickets.
 Serum Ca is ↓only in hypocalcemic rickets.
 Serum parathyroid hormone typically is ↑in hypocalcemic
rickets, in contrast it is N in hypophosphatemic rickets.
 25-OH vitamin D reflect the amount of vitamin D stored in
the body, and is ↓in vit D deficiency.
 1,25-OH2 vitamin D can be↓, N or ↑in hypocalcemic rickets
and usually is N or slightly ↑in hypophosphatemic rickets.

20.  Vitamin D. Stoss therapy: 300,000-600,000 IU orally or IM in
2-4 divided doses over one day.
 High dose vit D 2000-5000 IU orally for 4-6wks followed by
400 IU daily orally as maintenance.
 Adequate dietary Calcium & phosphorus provided by milk,
formula & other dairy products.
 Symptomatic hypocalcaemia need IV Cacl as 20mg/kg or Ca
gluconate as 100mg/kg as a bolus, followed by oral calcium
tapered over 2-6 weeks.

21.  To prevent rickets, it's important to focus on
two key factors: vitamin D and calcium intake.
Vitamin D helps your body absorb calcium,
which is essential for strong and healthy
bones. One of the best sources of vitamin D
is sunlight, so try to spend some time
outdoors each day. Additionally, include
foods like fatty fish, fortified dairy products,
and egg yolks in your diet to boost your
vitamin D levels.

22.  To ensure an adequate calcium intake,
consume foods like milk, cheese, yogurt,
leafy greens, and fortified plant-based milk
alternatives. It's also a good idea to consult
with a healthcare professional for
personalized advice and to discuss any
specific concerns you may have. Remember,
taking care of your bones now can help
prevent rickets and promote overall bone
health in the long run!