Metabolic Bone Disorders

Question 1

what is the LCOC?

Answer 1

lining cell osteocyte complexes

Question 2

what is the LCOC in charge of?

Answer 2

calcium levels pretty much

Question 3

what cell is in parathyroid that makes the hormone?

Answer 3

chief cells

Question 4

what are chief cells inhibited by?

Answer 4

high serum Ca and Vit D

Question 5

what does PTH target to lead to osteoclast activity?

Answer 5

bind to osteoblasts and makes them secrete RANK

Question 6

where does RANK go? what does it do?

Answer 6

to osteoclasts…binds RANK receptor and activates the osteoclasts

Question 7

what is the other name for Vit D3

Answer 7

cholecalciferol

Question 8

what does Vit D3 make available? what does this help with?

Answer 8

increases Ca and PO4 availability to help with bone mineralization

Question 9

name the three ways that Vit D3 increases Ca levels

Answer 9

increase absorption in gut
increase resorption in kidneys
increase release of minerals from osteoclasts

Question 10

does PTH increase or decrese Phosphate? what about Vit D3?

Answer 10

PTH decrease

D3 increases

Question 11

what is Alk phos a marker for?

Answer 11

bone turnover

Question 12

what is Ca and Phosphate used for?

Answer 12

mineralization of bone

Question 13

give the changes seen in calcium, PTH and alk phos for primary hyperparathyroidism

Answer 13

ca increase
PTH increase
increase alk phos

Question 14

what do primary hyperparathroidism patients present with? why?

Answer 14

stones
groans
bones
psychiatric overtones

all bc of hypercalcemia

Question 15

what is a disorder that primary hyperparathroidism can lead to?

Answer 15

osteitis fibrosa cystica

Question 16

what two things are seen in osteitis fibrosa cystica ?

Answer 16

subperiosteal bone resorption

cystic bone lesions called brown tumors

Question 17

secondary hyperparathyroidism is caused by what three things?

Answer 17

chronic renal disease
vit D deficiency
corticosteroids

Question 18

how does secondary hyperparathyroidism change calcium, PTH and alk phos levels?

Answer 18

Ca decreases
PTH increases
Alk phos increases

Question 19

?what is the etiology of secondary hyperparathyroidism

Answer 19

parathyroid hyperplasia in response to chronic increase in phosphate or decrease in calcium

Question 20

what are the main symptoms seen in secondary hyperparathyroidism?

Answer 20

bone symptoms of osteitis fibrosa cystica like brown tumor and high bone turnover rate

Question 21

what is cause of renal osteodystrophy?

Answer 21

bone issue with CKD

Question 22

what are two types of renal osteodystrphy?

Answer 22

high and low turnover

Question 23

high turnover renal osteodystrophy changes Ca, PTH and phosphate how?

Answer 23

Ca lower
phosphate higher
PTH higher

Question 24

what does high turnover renal osteodystrophy cause with Vit D3?

Answer 24

decrease in Vit D3

Question 25

in late renal osteodystrophy what can happen to the soft tissue?

Answer 25

can get soft tissue calcification

Question 26

low turnover renal osteodystrophy is often caused by what?

Answer 26

aluminum in dialysis leading to impairment of osteoblasts and clasts

Question 27

how to treat low turnover renal osteodystrophy?

Answer 27

phosphate binding agents or aluminum chelators

Question 28

hypoparathyroidism leads to what changes with Ca, PTH and phosphate?

Answer 28

high phos low Ca low PTh

Question 29

what is common cause of hypoparathyroidism ?

Answer 29

accidental surgical removal

Question 30

what is the hereditary cause of hypoparathyroidism ?

Answer 30

albright hereditary osteodystrophy

Question 31

how does albright hereditary osteodystrophy cause hypoparathyroidism?

Answer 31

parathyroid does not respond to PTH

Question 32

what are two signs of hypocalcemia?

Answer 32

trousseaus sign | chovstek sign

Question 33

what is trousseaus sign?

Answer 33

carpopedal spasm in muscles when cuff at elbow

Question 34

what is chovstek sign?

Answer 34

twitching of facial muscle with tapping over facial nerve

Question 35

does rickets have low or high serum Ca?

Answer 35

low

Question 36

what is issue in rickets/osteomalacia?

Answer 36

defective mineralization of bone

Question 37

how are bones described in rickets/osteomalacia?

Answer 37

soft and flexible

Question 38

what is most common cause of rickets/osteomalacia?

Answer 38

VIT D deficiency

Question 39

how do kids present with rickets/osteomalacia?

Answer 39

diffuse bone pain limp growth impairment bowed legs

Question 40

what will you see more of on histo with rickets/osteomalacia?

Answer 40

unmineralized osteoids

Question 41

what two changes to bone occur in rickets/osteomalacia?

Answer 41

physeal widening and metaphyseal flare

Question 42

what is rachitic rosary?

Answer 42

bumps on ribs seen in rickets/osteomalacia

Question 43

how do adults present with rickets/osteomalacia?

Answer 43

bone pain focal tenderness fractures

Question 44

osteoporosis presents with what changes in Ca, PTH and phos levels?

Answer 44

all are NORMAL

Question 45

what is issue in osteoporosis ?

Answer 45

normal mineralization but decreased bone quantity

Question 46

how does bone look on histo in osteoporosis ?

Answer 46

very soft with minimal mineralization

Question 47

what are two types of osteoporosis ?

Answer 47

type 1...post menopause | type 2...age related

Question 48

postmenopausal osteoporosis commonly presents with what two bone findings/

Answer 48

distal radius fractures | vertebral fractures

Question 49

postmenopausal osteoporosis is high or low bone turnover?

Answer 49

high turnover

Question 50

postmenopausal osteoporosis involves trabecular cortical or both types equally?

Answer 50

more trabecular involvement

Question 51

age related osteoporosis presents with what two bone findings?

Answer 51

proximal femur fracture | vertebral fractures

Question 52

age related osteoporosis has high or low turnover?

Answer 52

low turnover

Question 53

age related osteoporosis involves trabecular cortical or both types equally??

Answer 53

both types equally

Question 54

how can steroids cause osteoporosis?

Answer 54

inhibition of osteoblast precursors, decreased Ca absorption in gut, and secondary hyperparathyroidism

Question 55

how can hyperthroidism lead to secondary osteoporosis?

Answer 55

osteoclast stimulation

Question 56

how can prolonged inactivity lead to secondary osteoporosis?

Answer 56

if you dont use it you lose it

Question 57

osteogenesis imperfecta is a disorder of what?

Answer 57

bone formation...type I collagen defect

Question 58

what do you get a lot of in osteogenesis imperfecta?

Answer 58

fractures

Question 59

what are three associated findings in osteogenesis imperfecta?

Answer 59

blue sclera hearing loss tooth abnormalities

Question 60

osteogenesis imperfecta has many subtypes...what is most common?

Answer 60

type I AD

Question 61

osteopetrosis is a disorder of what?

Answer 61

bone resorption doesnt really occur

Question 62

osteopetrosis leads to what with bone?

Answer 62

really calcified and white bone

Question 63

how do you describe bone in osteopetrosis ?

Answer 63

heavy and brittle

Question 64

what are two bone findings or buzz words with osteopetrosis ?

Answer 64

erlenmeyer flask | marrow cavity loss

Question 65

paget disease is a disorder of what?

Answer 65

bone remodeling

Question 66

do you have low or high turnover of bone in paget disease?

Answer 66

high turnover

Question 67

what is elevated because of high turnover in paget disease?

Answer 67

elevated alk phos

Question 68

is bone more mature or immature in paget disease?

Answer 68

mixture of both

Question 69

on histo, what is characteristic finding of paget disease?

Answer 69

mosaic cement lines from continual remodeling

Question 70

how does paget disease present?

Answer 70

usually asymptomatic but can have bone pain, arthritis, high output heart failure

Question 71

what is a cancer risk with paget disease?

Answer 71

can develop into osteosarcoma