2. RICKETS AND OSTEOMALACIA
⢠Inadequate bone
mineralization.
⢠Excessive
unmineralized
osteoid.
⢠Osteomalacia adult
version of rickets.
⢠In rickets epiphyseal
involvement.
Different expression of
same disease
3.
4. Pathophysiology
⢠Deficiency of vit-D
⢠Hypocalcemia
⢠PTH secretion
⢠Plasma Ca
⢠Plasma P
⢠Bone resorption
⢠Bone formation for
compensation, lack of
Ca&P
⢠Rickets/osteomalacia
5. Epiphyseal Plate Abnormalities
⢠Resting & proliferative
zone not affected.
⢠zone of maturation:
irregularly distributed
cells.
⢠hypertrophic cells are
irregularly distributed
and the intervening
matrix bars cannot be
identified.
6. Cont..
NORMAL RICKETS
⢠honey comb
pattern vascular
growth distorted.
⢠Increase cartilage
cells and
unmineralized
matrix increase
length& width of
bones.
⢠Joint weight
produce âcuppingâ
18. Osteomalacia and osteoporosis
osteomalacia osteoporosis
unwell well
Generalized chronic ache Pain only after fracture
Muscle weak Muscle normal
Loosers zone No Loosers zone
Alkaline phosphatase
increased
Normal
Serum phosphorus
decreased
Normal
Ca X P < 2.4mmol/l >2.4 mmol/l
19. Treatment
⢠Vitamin âD deficiency rickets:
⢠Correction of cause of vitamin D deficiency:
adequate dietary supply, sun light exposer.
⢠15000Οg or 600,000 IU Vit D3 orally or IM
with calcium supplement.
⢠If healing occurs continue with 400 IU-1000
IU of Vit D3/day however elderly people
require 2000 IU/day vitamin D3.
⢠In Intestinal malabsorption: 50,000-100,000
IU vit D3/day with calcium supplements.
20. Renal tubular rickets & osteomalacia
⢠3 pathophysiological mechanisms:
1. increase clearance of PO4 by the PCT
(hypophosphatemic rickets).
2. A failure in the production of Hâş and its
substitution for fixed base in the DCT, (renal
tubular acidosis).
3. A failure in the conversion of 25-hydroxy
vitamin D to1, 25-dihydroxy vitamin D.
4. Combined lesion of both tubules which causes
the Fanconi group of rickets and osteomalacia.
21. Proximal tubular ricketic and
osteomalacic syndromes:
1.VDRR/hypophosphatemic rickets
or phosphate diabetes.
⢠+ve family history, X-linked
dominant.
⢠bony deformities present.
⢠Markedly reduced PO4, normal
serum calcium, No secondary
hyperparathyroidism, No Myopathy.
⢠Oral Neutral phosphate 1-4 gm/day
⢠Calcitriol (1, 25-DHCC) 2-
5Âľgm/kg/day)
22. 2.VDRR with Glycosuria
⢠less common than classic VDRR.
⢠abnormal resorptive mechanism for both
inorganic phosphate and glucose.
⢠Serum phosphate less, glycosuria.
⢠No evidence for genetic transmission.
⢠Diabetes not necessary to present.
⢠Vit-D= 0.5-1.5 mg/day(20,000-60,000 IU/day).
⢠Ca = 1gm/day
⢠Neutral Phosphates = 1.5 â 6 mg/day.
23. 3. Proximal Fanconi Syndrome
⢠defective reabsorption of phosphate, glucose,
and many amino acids.
⢠Autosomal recessive transmission.
⢠more florid, severe rachitic lesions and
pathological fractures.
⢠Later develop ch. Liver disease.
⢠Low serum po4, normal serum amino acid,
aminoaciduria.
⢠Vit-D=0.6 â 1mg/day(25,000-40,000 IU/day).
⢠Ca = 1gm/day and neutral phosphate=1-3g/d.
24. 4.Late onset VDRR/Hypophosphatemia.
⢠Normal in childhood, occurs early adulthood.
⢠Rare but one cause of unexplained bone loss,
joint pain in adults.
⢠No genetic error found.
⢠PTH responsible for phosphate leak rather
than tubular defect.
⢠Dramatic respond to vit-D(0.5-1.5 mg/day),
Ca(1gm/day), neutral phosphate(1-
3mg/day).
25. Proximal and Distal Renal Tubular
Rachitic and Osteomalacic Syndromes:
⢠Defective reabsorption in both PCT &
DCT.
⢠impaired reabsorption of water, fixed
base, protein, and bicarbonate.
⢠Results in acidosis, dehydration,
hyperproteinemia
⢠Four syndromes have been identified
in this group:
26. 1. proximal and distal Fanconi syndrome
(Debre De Toni Fanconi syndrome)
⢠Autosomal recessive transmission.
⢠Genetic swan neck deformity of renal tubule.
⢠Very severe hypophosphatemic ricket.
⢠Multiple # in few months of life.
⢠serum Ca, P, Na&K, Alk. Phos. Academia.
⢠Urine Pᴴ alkaline, glycosuria, amino aciduria.
⢠Vit-D=0.6 â 1mg/day(25,000-40,000 IU/day).
⢠Ca = 1gm/day and neutral phosphate=1-3g/d.
⢠Alkalizing solution, k- supplement.
27. 2. Lignac-Fanconi syndrome
⢠cystinosis, cystine storage disease.
⢠Cystine deposited through out the soft tissue.
⢠Autosomal recessive transmission.
⢠serum Ca, P, Na&K, Alk. Phos. Academia.
⢠Urine Pᴴ alkaline, glycosuria, amino aciduria.
⢠Vit-D=0.6 â 1mg/day(25,000-40,000 IU/day).
⢠Ca = 1gm/day and neutral phosphate=1-3g/d.
⢠Alkalizing solution, k- supplement.
28.
29. Renal Osteodystrophy:
⢠includes rickets or Osteomalacia, osteitis fibrosa
cystica, osteoporosis, osteosclerosis, and
metastatic calcification.
⢠Pathophysiology:
1. interferes with the conversion of 25-OH vitamin-
D to 1 ,25-dihydroxy vitamin-D.
2. Increase PTH secretion.
3. Hypocalcemia, hypocalciuric,
hyperphosphatemia.
4. Metastatic calcifications( arteries, cornea,).
30. Clinical features
⢠Growth impairment.
⢠Classic sign of rickets present.
⢠Ricketic rosary, Harrisons sulcus >
Craniotabes, Frontal bossing.
⢠Bowing and other deformity present.
⢠Wrist, ankle enlargement present.
⢠Epiphyseal separation.
⢠Arterial ,corneal calcification.
31. X- RAYS:
⢠Slipped capital femoral& humeral
epiphysis.
⢠Metaphyseal fracture.
⢠Cystic lesion in mandible.
⢠Soft tissue calcification(vessels, tendon)
⢠Subperiosteal erosion of bone (brown
tumors)
⢠Rugger- jercy spine.
34. Unusual Forms of Rickets and
Osteomalacia:
⢠Rickets and Osteomalacia Associated with
Benign Bone and Soft Tissue Tumors:
⢠hyposphatemic VDR Osteomalacia.
⢠Hemangioma of bone, giant-cell tumor,
reparative giant-cell granuloma, NOF,
Cavernous Hemangioma of the thigh, and
âossifying mesenchymal tumor "of the
larynx.
⢠Tertiary hyperparathyroidism.
⢠Ectopic vit-D antagonist secretion.
35. Rickets and Osteomalacia Associated
with Anticonvulsant Therapy:
⢠15% epileptic patient with long term anti epileptic
drugs( hydantoin, Phenobarbital).
⢠stimulation of hepatic microsomal P-450
enzymatic activity.
⢠An important syndrome to produce iatrogenic
cycle.
⢠usually responds well to vitamin D.
36. Vitamin-D dependent rickets and
osteomalacia
Type-I(pseudo vit-D deficient) Type-2 vit-D dependent
â˘Autosomal recessive
â˘Deficiency of 1ážł
hydroxylase.
â˘Severe ricketic syndrome.
â˘Secondary
hyperparathyroidism.
â˘Multiple #, Myopathy.
â˘Life time treatment with
1-OH vit-D.
â˘Autosomal recessive.
â˘Defect in vit-D receptors
in target cells.
â˘Adults and children
affected.
â˘Not responds to vit-D.
â˘Parenteral calcium is
needed.
37.
38. Orthopaedic Measures:
⢠Needed in established long bone
deformity.
⢠Surgery should be done after correction
of metabolic disorder.
⢠Very early stage different braces are used
accompanying systemic treatment.
⢠Surgery for deformity correction, may
need multiple surgery.