Endocrine Bone Flashcards
DX: Low serum calcium, low serum phosphate, raised ALP and raised PTH
osteomalacia
Dx: Hypercalcaemia, renal failure, high total protein
Multiple myloma
Dx: calcium, phosphate and ALP are normal
Osteopetrosis
Cinacalcet used in
primary hyperparathyroidism not fit for surgery
is a calcimimetic - a drug that ‘mimics’ the action of calcium on tissue by allosteric activation of the calcium-sensing receptor
Rx. severe hypocalcaemia (e.g. carpopedal spasm, tetany, seizures or prolonged QT interval)
IV calcium gluconate, 10ml of 10% solution over 10 minutes
ECG monitoring is recommended
What ALP an indicator of?
Bone metabolism and liver fx
High ALP
Bone - pagets
Liver : blk of bile ducts, cirrhosis, hepatitis, mono
Pregnancy
Why do bone cell secrete alp
Format need alkaline environment
What effect does PTH have on bone
Low levels Promotes bone formation
PTH regulates osteoclast maturation
High level = bone breakdown
PTH effects 3
Bone reabsorption
Increases ca2+
Decrease phosphate levels by urinary excretion
Factors that increase bone mass loss and increase chance of osteoporosis?
Low Estrogen
Hypo calcium
Genetics
Drugs heparin, thyoxine antconvulants
Low weight
Effect of estrogen on bone
Increase osteoblasts activity
Decreases osteoclast activity
What are bisphospjonates
What is Teriparatide ?
Recombinant parathyroid hormone
But actually active osteoBLASTs more than clasts
MOA hydrochlorothiazide in osteoporosis?
Promote ca retention in the distal convoluted tubule
Osteoblasts differ
Se of thiazides
MOA Denosmab
Inhibits osteoclasts maturation
Monoclonal antibody against rank-L
MOA Raloxifene
SERM - mimics estrogen = decreased risk of breast ca
MOA calcitonin
Decrease bone resorption
What is happens to bone in osteopetrosis?
Abnormally dense bone
Acid environment isnt there for resorption of old bone
Sx of osteopetrosis?
Radiological dx of osteopetrosis (2)
osteopetrosis labs
Thrombocytopenia
Reduced ca2+
Increased ALT
Rx osteopetrosis
None in adults
What is paget disease of the bone & causes
Abnormal bone remodeling esp. skull, lumbar & femurs
Genetic and infection
Stages of pagets 4
Sx of pagets
Skeleton sx of pagets
May lead to av shut leading to cardiac failure
Paget lab and radiology
Rx paget
Bisphosates
What is osteomalacia?
Deficiency in ca, vitd, phosphate
= inadequate bone mineralisation
Triggers of vit d deficiency
Liver and kidney failure
Liver failure and vit d
25 hyroxy is lacking
Kidney failure and vit d
25 hydroxy lacking
What happens with to parathyroid with vit d
Hyper parathyroidism
Labs in osteomalacia
High ALT
Low ca2+ (May lead to high PTH & low serum phosphate )
Low vit d
Radiology of osteomalacia
Rx osteomalacia
Vit d
4 bone disorders
Osteoporosis
Osteopetrosis
Peget
Osteomalacia
Medication Causes of of HYPERca2
Lithium
Thiazides
Vitd
Calcium containing ant acids
ECG changes with hyperCa2+
Bradycardia, av block, shortened QT
Fx of PTH 3
Causes and labs in primary hyper calcium
Tumour
Pth high ca2+ high
Causes of 2ndary hyper parathyroid
Low Vit d or CKD
Pth high
LOW ca or normal
Cause of tertiary hyper parathyroidism
Hyperplasia
High PTH
HIGH ca
