Metabolic Bone Disease Flashcards
What protein binds calcium in the blood? How much calcium does it bind?
Every g/DL Albumin binds 0.8 mg/dL of Ca
How to calculate corrected Calcium?
CC = MC + (A-normal A) * 0.8
Guidelines for Surgery in Asymptomatic Primary Hypoparathyroidism?
- Serum Ca > 1 mg/DL over normal
- T-Score < -2.5
- Fragility fracture on image
Medical Treatment Hyperparathyroidism
- Cinacalct -> INC Ca receptor sensitivity
Rickets vs Osteomalacia
Rickets -> failure of mineralizations of new bone at growth plates
Osteomalacia -> failure of mineralization of newly formed osteoid at sites of bone turnover
Most common cause of Rickets
Def in Vit D, Ca, or Phosphorus
Renal Tubular Acidosis Types
Type I: Distal tubule unable to secrete H+ -> Loow Bicarbonate, High urine pH; Hypokalemia + nephrolithiasis
Type II: A/S Fanconi Syndrome: Excessive bicarbonate loss in proximal tubule; Variable pH usually high (>6.5) + DEC Bicarbonate
Renal Osteodystrophy
- S/S
- Labs
- Tx
- S/S: Bone pain, muscle weakness, short stature (rickets), hyperparathyroidism, osteoporosis, bone cysts
- Labs: Variable Ca; High phosphate
- Tx: Manage Phosphatel Calcitriol cinecalcet; avid aluminum in diasylates
Osteoporosis T-score
< -2.5
Endocrine causes of Osteoporosis
- Hypogonadism
- Hyperthyroidism
- Hyperparathyroidism
- Hypercortisolism
- Vit D Deficiency
Biggest Iatrogenic cause OP
Corticosteroids
Treating OP
- Sufficient Ca in early years
- Reduce behaviors (smoking, EtOH, weight, etc)
- Surgical (kyphoplasty, vertebroplasty)
- Medication (Biphosphonates, supplements, estrogen)
Pseudohypoparathyroidism
- A/S
- LabDx
- S/S
- A/S: Albright’s hereditary osteodystrophy
- LabDx: PTH does NOT increase in phosphate diuresis or increase serum Calcium
- s/s: shortened metacarpals; short stature; other bone malformations
