Flashcards in 21. Osteomalacia/rickets Deck (13)
Vitamin D deficiency can cause
adults --> osteomalacia ( defective mineralization of osteoid)
children --> rickets ( defective mineralization of cartilaginous growth plates )
Vitamin D deficiency --> condition of boones ( mechanism
Vitamin D deficiency --> defective mineralization / calcification of osteoid --> soft bones that bow out
Vitamin D deficiency - serum P level ( mechanism
decreased vitamin D --> decreased serum Ca2+ --> increased PTH secretion --> DECREASED SERUM Pi
Vitamin D deficiency - Ca2+
Vitamin D deficiency - ALP level ( why)
increased ALP 9 because of osteoblast hyperactivity - osteoblasts require alkaline environment )
osteomalacia - x rays
osteopenia and looser zones ( pseudofractures _
rickets - x-rays
epiphyseal widening and metaphyseal cupping / fraying
children with rickts presentation
bow legs . bead - like costochondreal jucntions
(rachitic rosary craniotabes ( soft skull )
• What disorder is caused by defective mineralization of osteoid leading to soft bones?
• A 2-year-old child has bowing of his legs. His labs show elevated PTH levels but decreased Ca2+ levels. What is the primary deficiency?
Vitamin D (this child has rickets)
• A patient is diagnosed with osteomalacia. What is the pathophysiology of this condition?
High PTH decreases serum phosphate, causing demineralization/soft bones (low vitamin D leads to low serum calcium, triggering PTH secretion)
• Parathyroid hormone is increased in osteomalacia, which activates what type of cell to produce what enzyme?
Osteoblasts are stimulated to make alkaline phosphatase, because they need an alkaline environment to function properly