Rickets

1. Rickets

2. lack of vitamin D, calcium, or phosphate, which leads to softening and weakening of the bones. Defective mineralization of bone matrix – excessive unmineralised osteoid Definition:

3. Vitamin D helps the body properly control calcium and phosphate levels in the body. When the body is deficient in vitamin D, it is unable to properly control calcium and phosphate levels calcium and phosphorous are found in milk and green vegetables.

4. Defective Vitamin D metabolism – lowering of calcitriol - intestinal malabsorption of calcium - reduction of serum calcium – Parathyroid stimulation – normalised S.calcium at the expense of reduced S.Phosphate Pathophysiology

5. Parathormone – Osteoblastic activity - ALP activity – Defective Osteoid mineralization

6. ultraviolet rays 7-Dihydrocholesterol Cholecalciferol (Vitamin D3)- in dermis Vit D2 absorbed thru small intestine Transport in serum- binds with X-globulin 25-Hydroxylation in Liver 1,25- Dihyroxylation in Kidney – active form

7. Nutritional Absorptive Renal Others Aetiology

8. Decrease in effect & amount of Sunlight Bread/Chapathi rich in Phytate bind dietary calcium – reduced absorption Infants who are exclusively breastfed may develop vitamin D deficiency. Poor Dietary intake of Ca & Vit D Malabsorption disorders – Coeliac d/s, hepatic osteodystrophy, lactose intolerance Aetiology

9. Renal – Renal osteodystrophy, Nephrectomy, renal failure, hypoparathyroidism, X-linked hypophosphatemia/Vit D resistant rickets Vitamin dependant Type I (Inability to hydroxylate) Vitamin dependant Type II (Receptor insensitivity) Anticonvulsant therapy( 25OH in liver)

10. Failure of deposition of Ca along mature cartilage cell columns Disorderly invasion of cartilage by blood vessels Lack of reabsorption at the zone of provisional calcification Increased thickness of epiphyseal plate Pathology

11. Abundant osteoid with Defective mineralization No resorption of uncalcified osteoid by osteoclasts Normal osteoblast – laid irregularly Abnormal arrangement of collagen bundles in compact bone

12. Long bones bent when child starts crawling/walking Deformities

13. Valgus deformity

14. Windswept deformity

15. Varus deformity

16. Rachitic rosary

17. Kyphoscoliosis

18. Bone pain or tenderness Arms Legs Spine Pelvis Skeletal deformities Bowlegs pigeon chest rachitic rosary Frontal bossing Spine deformities (spine curves abnormally, including scoliosis or kyphosis ) Pelvic deformities Symptoms:

19. Increased tendency toward bone fractures 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 ) Decreased muscle tone (loss of muscle strength) Muscle cramps Impaired growth Short stature

20. Acute stage Normal epiphyseal appearance clouded Metaphyseal splaying Thickened periosteum Radiology

21. Epiphysis Mottled & irregular Metaphysis ragged & broader Periosteal thickening disappears Second stage

22. Dense shadow Dense line at the end of metaphysis- deposition of Ca Stage of repair Third stage

23. Increase in breadth of metaphysis Clearly defined bone Normal content of Ca salts Bone completely repaired Fourth Stage

24. Serum Ca low or normal. Tetany -prolonged muscle spasm. Chvostek's sign may be positive (a spasm of facial muscles occurs when the facial nerve is tapped) S.Phosphorus may be low. S.ALP may be high. ABG may reveal metabolic acidosis Urinary Ca may be low . Biochemistry

25. 24-hydroxylase assay – for vitamin D dependency rickets Serum 25-OH vitamin levels A bone biopsy is rarely performed but will confirm rickets.

26. Congenital syphilis Infantile scurvy D/D

27. Goals - relieve symptoms and correct the cause of the condition. Underlying cause must be treated to prevent recurrence. Treatment:

28. Medical treatment Prevention of deformity Treatment of existing deformity

29. Dietary sources of vitamin D include fish, liver, milk and cheese. Exposure to moderate amounts of sunlight is encouraged. Reduce cereal containing phytates Supplemention of Calcium and Vitamin D – 3000 i.u./day Medical Treatment

30. Before treatment and 2 years after treatment with calcium

31. Control of movements – reduced pressure upon limbs (soft bones easily bent by pressure / muscle strain) Positioning or bracing with ‘rickets’ splints may be used. Prevention of deformity

32. Correction by splinting In young children below 4 yrs Useful in lower limbs Continuous supervision needed to prevent sores Treatment of established deformity

33. Correction by osteotomy When deformity is near a joint At least stage 3 in radiograph

34. Chronic skeletal pain Skeletal deformities Skeletal fractures, may occur without cause Complications:

35. Rickets of prematurity Very premature infants at risk Risk factors- hepatobiliary d/s, TPN, Diuretic therapy, chest percussion therapy Pathologic # in NICU Readily heal with treatment Other types

36. Antiepileptic medications Induce microsomal P-450 enz Decreased Vit D Should be suspected in neurologic patients having seizures Start having frequent # Drug induced

37. Familial hypophosphatemic rickets X-linked dominant (MC)- Mutn in PEX gene Aut dominant 12p13 – phosphatonins – fgf 23 – cause phosphaturia Aut recessive Vit D resistant rickets

38. Renal tubule unable to retain PO4 End organ insensitivity to vit D (AR) Kidney unable to perform 2 nd hydroxylation Renal tubular acidosis (kidney excretes fixed base and wastes bicarbonate) Ca ppt – renal calcinosis Abnormality

39. Older age Delayed walking, angular deformities Systemic manifestn – irritability and apathy minimal Treatment – Oral Phosphorus , Vit D (Compl – nephrocalcinosis) Growth hormone – increased height, increased PO4, reduced Nephrocalcinosis C/F

40. Surgery not efficacious – multilevel osteotomy to correct mechanical axis Recurrent deformity common Surgery when - gait compromised/severe pain

41. Oncogenic hypophosphatemic osteomalacia Asso with Neurofibromatosis, fibrous dysplasia Osteoblastoma, hemangiopericytoma of bone, skin tumors (disrupts renal tubular abs of po4) Secrete phosphatonins Resolve with excision of tumor Tumor related hypoPO4 rickets

42. C/C pyelonephritis Congenital Abnormalities Polycystic kidney d/s Secondary hyperparathyroidism Leads to actvn of osteoclast and resorption of bone (high turn over d/s) Renal Osteodystrophy

43. Glomerulus unable to excrete Phosphorus Vit D prodn reduced Ca abs from S.Intestine reduced PTH triggered Increased S.Ca – bone demineralization Precipitate in cornea, skin, blood vessels

44. C/F similar to Nutritional. Angular deformity, SCFE, AVN Radiography – cuppping of physis not present Subperiosteal resorption in phalanges, MC and ulna (feature of Hyperparathyroidism) Osteosclerosis of skull, rugger jersey spine Lytic areas in long bones (Brown tumors) Treat underlying d/s- Ca, Vit D, growth hormone, osteotomy, Ilizarov

45. Ca Normal or low in all Phosphate is reduced in all except Renal Osteodystrophy ALP and PTH high in all 25 OH Vit D N or high in all except nutritional (decreased) 1,25 (OH)2 N or low in all except Vit D dependent typeII (receptor insensitivity)

46. Maintain an adequate intake of calcium, phosphorus, and vitamin D. This may require dietary supplements in people who have gastrointestinal or other disorders Renal causes of vitamin D should be treated promptly. Prevention:

47. Levels of calcium and phosphorus should be monitored regularly in people who have renal disorders . Genetic counseling may help people with a family history of inherited disorders that can cause rickets.