Mod 1 lecture 2: calcium homeostasis

Question 1

what is the presentation of hypercalcemia

Answer 1

stones, moans, bones and psychiatric overtones
ECG = shortened QT, ST depression, AV block

Question 2

what are the common causes of hypercalcemia

Answer 2

hyperparathyroidism, malignancy, granulomatous disease, thiazide, lithium, pancreatitis

Question 3

what are the interventions for hypercalcemia

Answer 3

IV hydration, calcitonin, bisophosphonates, loop diuretics, glucocorticoids, denosumab, dialysis

Question 4

what build bone by secreting collagen and catalyzing mineralization

Answer 4

osteoblasts

Question 5

what dissolve bone by secreting acid and collagenases

Answer 5

osteoclasts

Question 6

what at low intermittent levels, have an anabolic effect on osteoblasts (build bone)

Answer 6

parathyroid hormone (PTH)

Question 7

what inhibits apoptosis in osteoblasts and induces apoptosis in osteoblasts

Answer 7

estrogen

Question 8

what does estrogen deficiency lead to

Answer 8

excess cycles of remodeling and bone resorption resulting in osteoporosis

Question 9

what stimulates calcium deposition in bones, decrease calcium uptake in kidneys

Answer 9

calcitionin

Question 10

what increases intestinal and renal uptake of Calcium and phosphate and stimulates calcium release from bones - promotes bone mineralization

Answer 10

vitamin D

Question 11

what are regulators of bone mineral and calcium homeostasis

Answer 11

osteoblasts
osteoclasts
PTH
estrogen
calcitonin
vitamin D

Question 12

what is the MAO for bisphosphonates

Answer 12

inhibits osteoclast activity, reducing bone resorption and turnover

Question 13

what are the indications for alendronate

Answer 13

osteoporosis, paget disease of bone, osteopenia (in non-ambulatory patients)

Question 14

what are the indications for risedronate

Answer 14

osteoporosis, paget disease of bone

Question 15

what are the indications for ibandronate

Answer 15

osteoporosis

Question 16

what are the indications for zoledronic acid

Answer 16

osteoporosis, malignant hypercalcemia, bone metastasis, multiple myeloma

Question 17

what are the bisphosphonates

Answer 17

aldendronate
risedronate
ibrandronate
zoledronic acid

Question 18

what are the side effects of bisphosphonates

Answer 18

bone, joint and muscle pain
N, abd pain, heartburn, diarrhea, constipation
irritation to upper GI mucosa (risedronate < alendronate)
HA
atypical femur fractures, osteonecrosis of the jaw
flu-like symptoms with IV bisphosphonates
hypocalemia - Ca and Vit. D supplementation recommended

Question 19

what are the contraindications for bisphosophonates

Answer 19

esophageal disorders (achalasia, esophageal strictures, osophageal varices, Barrett’s esophagus)
renal insufficiency (CrCl < 35)
hypocalcemia
food interferes with absorption - take with water on empty stomach and wait 30-60 minutes before eating

Question 20

what is the MOA of Calcitonin

Answer 20

antagonizes the effect of PTH, inhibits osteoclast activity and promotes renal excretion of Ca2+

Question 21

what are the indications of calcitonin

Answer 21

hypercalcemia, paget disease of bone, postmenopausal osteoporosis, pain from osteoporotic fracture

Question 22

what are the AE of calcitonin

Answer 22

rhinitis, epistaxis, back pain, N/V, bronchospasms, hypocalcemia, anaphylaxis (rare)

Question 23

what is the MOA for vitamin D

Answer 23

cholecalciferol (vit D3) is a provitamin. active metabolite 1,25-dihydroxyvitamin D stimulates calcium absorption from small intestine and promotes bone mineralization

Question 24

what are the indicatiosn for vitamin D

Answer 24

vitamin D deficiency, osteopososis, hypoparathyroidism

Question 25

what are the contraindications of vitamin D

Answer 25

hypercalcemia, primary hyperparathyroidism, sarcoidosis

Question 26

what is the MOA for Calcitrol

Answer 26

vitamin D analog - stimulates calcium and phosphorus absorption, decrease PTH synthesis, stimulates bone mineralization

Question 27

what are the indications for calcitriol

Answer 27

renal failure, hypoparathyroidism, rickets, hypophosphatemia

Question 28

what are the AE of calcitriol

Answer 28

hypercalcemia, hyperphoephatemia, N/V

Question 29

what are the contraindications of Calcitriol

Answer 29

pancreatitis, soft tissue calcification, arrhythmias

Question 30

What is the MOA for denosumab

Answer 30

recombinant antibody that inhibits RANK-ligand to bind to RANK (antiresorptive)

Question 31

what are the indications for denosumab

Answer 31

osteoporosis, cannot tolerate or unresponsive to bisphosphonates, renal impairment

Question 32

what are the SE of denosumab

Answer 32

osteonecrosis of the jaw, atypical subtrochanteric fracture, bone pain

Question 33

what are the contraindications of denosumab

Answer 33

hypocalcemia

Question 34

What is the MOA of teriparatide (forteo)

Answer 34

recombinant PTH anabolic effect on bone metabolism by stimulating bone formation and activating bone remodeling treatment duration < 2 years in lifetime

Question 35

what are the indications for teriparatide

Answer 35

osteoporosis (but not used often)

Question 36

what are the AE of teriparatide

Answer 36

generally well tolerated. hypercalcemia and hypercalciuria. orthostatic hypotension US boxed warning: risk of Osteosarcoma

Question 37

what are the contraindications of teriparatide

Answer 37

hypercalcemia, severe renal impairment

Question 38

What is the MOA for Raloxifene

Answer 38

selective estrogen receptor modifier (SERM) acts like estrogen agonist in bone thereby decreasing bone resorption and overall bone turnover bone density is increased

Question 39

what are the indications for Raloxifene

Answer 39

osteoporosis in postmenopausal women

Question 40

what are the AE of Raloxifene

Answer 40

hot flashes, leg cramps, peripheral edema, DVT/PE

Question 41

what are the contraindications of Raloxifene

Answer 41

history of DVT/PE, pregnancy

Question 42

what are the effects of thiazides (HCTZ) on calcium levels

Answer 42

decrease urinary Ca2+ excretion inhibits secretion of Calcium sometimes leading to elevated calcium levels in the blood

Question 43

what are the effects of loops diuretics (furosemide) on calcium levels

Answer 43

increase urinary calcium concentration useful in treatment of hypercalcemia because it stimulates tubular calcium excretion

Question 44

what are the toxicity symtpoms of fluoride

Answer 44

GI effects such as N/V/D, severe cases renal or cardiac dysfunction

Question 45

where is the total body fluoride contained

Answer 45

in bones and teeth