Rickets

• What is rickets?


  Paediatric skeletal disorder

  Caused by deficiency or impaired metabolism of vitamin D, calcium or phosphate
• What can cause prolonged vitamin D deficiency?


  Poor nutrition

  Insufficient sun exposure

  Malabsorption syndromes
• What are the signs & symptoms of rickets?


  Bowed legs or knock knees (genu valgum)

  Bone pain

  Stunted growth

  Dental deformities

  Skeletal deformities (pigeon chest or spinal curvature)

  Rachitic rosary - swelling of costochondral junctions

  Proximal muscle weakness

  Severe

  • bone fragility & fractures
  • hypocalcaemia -> irritability, seizures & intellectual disability
  • dilated cardiomyopathy
• What are the DDx of rickets?


  Osteomalacia

  Hypophosphataemia

  Osteogenesis imperfecta

  Hereditary hypophosphataemic rickets
• What are the Inx of rickets?


  Obs

  Full Hx & examination

  Urinalysis

  Bloods (bone profile, vitamin D)

  XRs of affected bones -> typical changes = cupping, fraying & metaphyseal widening
• What is the management of rickets?


  Supplements (vitamin D, calcium & phosphorus)

  Diet & lifestyle modification -> adequate sun exposure, diet rich in vit D, calcium & phosphate

  Orthopaedic surgery (severe cases)
• What are the possible complications of rickets?


  Psychological complications -> due to chronic bone & joint pain

  Dental caries -> secondary to dental deformities

  Hypocalcaemia -> can lead to seizure, tetany & laryngospasm (can cause apnoea or stridor)
• Pathophys - rickets


  Low vit D → less intestinal absorption of Ca & phosphate → hypo Ca & hypo PO4 → increase PTH → more renal reabsorption of Ca & less PO4 reabsorption → exacerbates hypo PO4

  High PTH → more osteoclast activity (resorption) → lowers PO4 levels (released in blood & excreted via kidneys)

  Hypo Ca & hypo PO4 → disrupts normal bone mineralisation → soft pliable bones

  In growth plates of long bones → chondrocytes prolif & differ for bone growth → hypo PO4 → widening & disorganisation of growth plate → skeletal deformities
• What are the RFs for rickets?


  Age 6-24 months

  Inadequate sunlight exposure

  Breastfeeding

  Ca+2 deficiency

  Phosphate deficiency

  FHx

  Meds (antacids, loop diuretics, corticosteroids, anticonvulsants)