Bone Mineralization-----------------------------------EXAM2

Question 1

What is balance?

Answer 1

Long term adjustments to maintain total Ca2+ [ ]

Question 2

What are osteoclasts responsible for?

Answer 2

Removal of bone matrix

Question 3

What are osteoblasts responsible for?

Answer 3

Produce bone matrix , control mineralization

Question 4

5. What are the two major mineral constituents?

Answer 4

Calcium

phosphate

Question 5

T/F: Small amounts of Ca exist in the free/active form?

Answer 5

True

Question 6

7. What percent of phosphate exists in crystalline form?

Answer 6

85%

Question 7

Name the two 1o regulators for calcium/phosphate?

Answer 7

Parathyroid Hormone

Vitamin D

Question 8

9. What are the 2o regulators for calcium/phosphate?

Answer 8

Calcitonin, Glucocorticoids, Estrogen

Question 9

Parathyroid H

1. Main Goals? *****

Answer 9

Inc calcium

Dec phosphate

Question 10

Effects on the Kidneys?

Answer 10

􏰀 Increase Calcium, Magnesium reabsorption

􏰀 Decrease Phosphate reabsorption at distal tubule

􏰀 Stimulate the production of Calcitriol (1,25 [OH]2D)

Question 11

PTH

Effects on Intestines?

Answer 11

No Direct Effect

Indirectly promotes absorption of Calcium through
stimulation of Vitamin D

Question 12

Vitamin D

T/F. When pts aren’t exposed to UV light you may supplement with Vitamin D

Answer 12

T

Question 13

Vitamin D

Activation of Vitamin D is?

Answer 13

Endogenous Production

Sun-Liver-Kidney

Question 14

3. What is the active form of Vitamin D

Answer 14

Clcitriol

Doesnt need hydrox in kidney to be active

Question 15

Main Goals of Vitamin D?

Answer 15

􏰀 Increase Calcium

􏰀 Increase Phosphate

Question 16

5. Sites of Action

Vitamin D

Answer 16

Intestine, Bone, and Kidneys

Question 17

What is Paget’s Disease?

Answer 17

􏰀 Local areas of bone become Hyperactive
􏰀 Replace normal matrix w/ softened & enlarged bone
􏰀 Seen mainly in males and bowed legs

Question 18

What is the normal total serum concentration of Ca2+?

The normal ionized serum Ca2+ concentrations?

** calcium must be adjusted for hypoalbuminemia

Answer 18

􏰀 8.5 – 10.5 mg/dL
􏰀 4.6 – 5.1 mg/dL

Question 19

3. T/F. Calcium must be adjusted for hypo-albuminemia.

Answer 19

T

Question 20

. What are the effects of alkalosis?

Answer 20

􏰀 Decreased calcium concentrations (because calcium protein binding increased)

􏰀 Calcium protein binding increased

Question 21

What are the effects of acidosis?

Answer 21

􏰀 Increased calcium concentrations
􏰀 Calcium protein binding decreased

Question 22

Hypocalcemia

1. What is the hallmark sign of hypocalcemia? ****

Answer 22

Tetany

Question 23

2. T/F. Hypocalcemia associated with hypo-albuminemia does not need treatment?

Answer 23

T

Question 24

What is the goal of therapy in acute hypocalcemia?

Answer 24

Administer 200 – 300mg

of Ca2+ by IV

Question 25

What Ca2+ agent is preferred to correct hypocalcemia?

Answer 25

Calcium gluconate (2-3 grams)

Question 26

What are some ADRs with rapid administration (IV) of calcium?

Answer 26

Hypotension 􏰀 Bradycardia 􏰀 Cardiac asystole

Question 27

6. What is the T(x) if patient has chronic hypocalcemia?

Answer 27

􏰀 Calcium supplementation w/ oral calcium salts 􏰀 Vitamin D supplementation

Question 28

What type of bone is lost in osteoporosis?

Answer 28

Trabecular and cortical bone

Question 29

What is the epidemiology of osteoporosis? | * women & Caucasian/Asians mostly

Answer 29

􏰀 Women lose 35% of cortical bone over lifetime 􏰁bone mass declines 3% per decade and 9% after menopause 􏰀 Men lose 23% over lifetime

Question 30

Who is at risk for corticosteroid induced osteoporosis?

Answer 30

Asthmatics, ** CT disorders 􏰀 Rheumatoid arthritis, ** transplant patients

Question 31

4. What is the optimal Ca2+ intake for men?

Answer 31

􏰀 25-65 years􏰁1000mg 􏰀 >65 years􏰁1500mg

Question 32

5. What is the optimal Ca2+ intake for women? *****

Answer 32

􏰀 25-50 years􏰁1000mg 􏰀 Pregnant/nursing 􏰁 1200mg 􏰀 Post menopause􏰁1000 or 1500mg (+/- estrogen) 􏰀 >65 years􏰁1500mg

Question 33

What are some dietary sources of Calcium?

Answer 33

􏰀 Dairy products 􏰀 Shellfish 􏰀 Vegetables (green/leafy) & tofu

Question 34

What type of supplementation should you take if you have osteoporosis?

Answer 34

􏰀 Vitamin D at 400 – 800 IU per day 􏰀 Calcium (elemental) * carbonate􏰁40% * citrate􏰁21% * lactate􏰁13% * gluconate􏰁9%

Question 35

What agents are most common for T(x)?

Answer 35

Bisphosphonates (inhibit bone reabsorption)

Question 36

Which bisphos ↑ bone mass 2-3%

Answer 36

Etidronate (1st generation)

Question 37

10. Which bisphos is not approved for osteoporosis?

Answer 37

Pamidronate (2nd generation)

Question 38

What does alendronate (2nd generation) do?

Answer 38

􏰀 Normal bone forms w/ drug use at 3 months 􏰀 Do not allow pt to lie down w/in 45min of taking dose

Question 39

Name another bisphos 2nd generation drug?

Answer 39

􏰀 Risedronate 􏰀 Don’t let pt lie down w/in 45min of taking dose because can cause erosive esophagitis

Question 40

13. Name a newer bisphos for osteoporosis T(x)?

Answer 40

􏰀 Ibandronate (Boniva) 􏰀 Can take daily, once a month, or injection every 3 mths

Question 41

How is calcitonin taken for osteoporosis?

Answer 41

IM/SQ injection 􏰀 Nasal spray

Question 42

What are some ADRs of calcitonin for osteoporosis?

Answer 42

􏰀 Resistance due to formation of Abs after 2-18mths 􏰀 Local irritation at injection site 􏰀 Rhinitis, irritation, erythema from nasal spray

Question 43

What is homeostasis?

Answer 43

Immediate adjustments to maintain free Ca2+ [ ]

Question 44

PTH

Answer 44

Inc Ca, dec P

Question 45

Treatment for hypercalcium Loop Bi CoCa w Hydration

Answer 45

Loop diuretic

Question 46

Bone mineral homeostasis Homeostasis- immediate

Answer 46

Balance- long term

Question 47

Hypercalcemia What should you do if total Ca2+ is

Answer 47

Initiate therapy only if patient is symptomatic

Question 48

What should you do if total Ca2+ is >13.5 – 14 mg/dL?

Answer 48

Initiate therapy regardless of symptomatology

Question 49

What are basic signs/symptoms of hypercalcemia?

Answer 49

Neurological, GI, Renal, and CV effects 􏰀 Extra-skeletal calcification

Question 50

What is the normal pharm T(x) for hypercalcemia?

Answer 50

􏰀 Hydration with normal saline 􏰀 Acute management give 2-6 liters w/in 24hrs 􏰀 See 1.6-2.4 mg/dL ↓ in Ca2+ concentrations

Question 51

What do loop diuretics do in hypercalcemia? Furosemide Bumetanide Toresemide

Answer 51

􏰀 Inhibit Ca2+ reabsorption in ascending loop of Henle

Question 52

What do bisphosphates do in hypercalcemia? *******

Answer 52

􏰀 Inhibit attachment of osteoclasts to the mineralized matrix 􏰀 Ca2+ concentrations decline in about 3 days 􏰀 Nadir (lowest Ca2+ concentration) is reached in 7 days 􏰀 Wait at least 7 days before you give another dose 􏰀 Pemidronate is most common bisphos for T(x)

Question 53

What is calcitonin?

Answer 53

􏰀 A secondary regulator of bone homeostasis | 􏰀 Hormone made by the C- cells of thyroid

Question 54

Main goals of calcitonin?

Answer 54

􏰀 Decrease calcium 􏰀 Decrease phosphate

Question 55

Where are the calcitonin sites of action?

Answer 55

Bone (primary) and kidney

Question 56

What are corticosteroids?

Answer 56

􏰀 Secondary regulators of bone homeostasis 􏰀 Made by the adrenal cortex 􏰀 Decrease Ca2+ levels w/in 7 days 􏰀 T(x) limited to granulomatous/lymphoproliferative dz

Question 57

14. Where are the corticosteroid sites of action?

Answer 57

􏰀 Intestine and bone 􏰀 Kidneys | 􏰁increase renal excretion of Ca2+

Question 58

What is the normal serum phosphate concentration?

Answer 58

3 -4.5 mg/dL

Question 59

T/F. Signs/symptoms of hyperphosphatemia are the same as hypocalcemia?

Answer 59

T

Question 60

What are the important pharmacological phosphate binding agents used to treat hyperphosphatemia?

Answer 60

Aluminum, calcium, and magnesium containing salts which help to bind phosphate

Question 61

What is an ADR when using calcium salts for hyper?

Answer 61

Increased Ca2+ concentrations may predispose patients to metastatic calcification

Question 62

What is the action of calcium acetate (Phoslo)

Answer 62

􏰀 Binds twice as much phosphate as other Ca2+ salts 􏰀 Limits GI absorption􏰁diarrhea

Question 63

T/F. Moderate concentrations from 1 – 2.5mg/dL are much more common than severe concentrations (

Answer 63

T

Question 64

What kind of therapy is required in severe hypophosphatemia?

Answer 64

􏰀 Intravenous therapy * use ↓ doses in pts w/ renal dysfunction 􏰀 Oral therapy is assoc w/ osmotic diarrhea

Question 65

Osteoporosis tr

Answer 65

Biphosphonates-seen increaing bone in 3 m/ dont lie down within 30 min Ibandronate- once a month(oral), every 3 m(inje) Denosumab- rankl ( only works on osteoblast)