Parathyroid Function: Calc reg (start for exam 2)

Question 1

Describe Calcium jobs
m
o
m
b
n
i

Answer 1

maintained in narrow range
optical nerve impulse
muscle contractions
blood coag
normal secretions
initial adhesion

Question 2

What is calcium regulated by

Answer 2

hormonal control

Question 3

Describe PTH
secreted from…
what receptors
prim targets?

Answer 3

secreted from glands adjacent to thyroid
calcium sensing receptors
primary targets bone and kidney

Question 4

Describe bone and calcium
mobilizes….
increases..
releases…

Answer 4

mobilizes calcium from bone which increases bone reabsorbtion and releases minerals into blood stream

Question 5

Describe Kidney 3 effects
inc reab
inc phos
enhance a

Answer 5

increased reabsorb of renal tube calcium
increased phosph excretion
enhanced alpha-hydrox of 25 hydrox Vit D

Question 6

Describe calcitriol
active met of….induces active re …

Answer 6

active met of Vit. D induces active absorption of calcium in small intestine

Question 7

Describe low blood calcium

Answer 7

sensed by parathroid CSR - secretes PTH - activates cascade to restore normal blood ca

Question 8

Describe Vit D hormone

Answer 8

steriod hormone from cholesterol

Question 9

Describe Vit D3

Answer 9

rare in nature, liver/seafood, fortified milk, more potent then D2

Question 10

Describe Vit D2

Answer 10

edible mushrooms

Question 11

Describe endogenous VIT D
synth of
what is a natural ligand for…
treats 2nd….due to

Answer 11

synth of Vit D from sunshine
1,25 (OH) 2D - natural ligand for VIT D steriod receptor
(treats 2nd hyperparathy due to chronic renal failure)

Question 12

Activated Vit D
causes active…
how much absorbed passively
absence of?

Answer 12

causes active adsorbtion of calcium in small intestine
5-10% absorb passively
absence of phosphate (higher passive absorb)

Question 13

Describe hypocalcemia

Answer 13

decreased plasma [] calcium
lack of Vit D

Question 14

Describe Bones, what stimulates maturation

Answer 14

active Vit D stimulates osteoclast maturation

Question 15

Describe the steps ca+2 falling
stimulates
increases
decreased
increases 1

Answer 15

stimulates PTH, increases bone reabs, decreases urinary loss, Increases 1,25(OH)sD production

Question 16

Describe PTH
maintains…
P/V

3 organs

Answer 16

maintains optimal calcium levels: PTH/Vit D work w/ 3 organs

3 organs: GI/Kidney/Bone

Question 17

Describe GI regulation of PTH
norm..
altered function causes?

Answer 17

normal func required/opt absorbtion
altered intestinal funct: gastric bypass
bowel fistula
short bowel syndrome

Question 18

Role of kidneys in PTH
metabolism
renal failure…
..incr
state?

Answer 18

calcium metabolism
renal failure = dist in calcium/phosph metabolism
PTH inc renal tube aborb of calcium reducing renal loss
Hypercalcemia

Question 19

Bone physiology
how much calcium
storge of?

Answer 19

1kg of calcium
stoarge of calcium/magn./phosph

Question 20

Describe bone turnover (remodeling)

Answer 20

reg/coupled process, breakdown/creation
if “uncoupling” occurs mismatched form/reabs
inc fracture

Question 21

What are bone turn over markers used for?

Answer 21

to monitor therapy/predict bone fract risk

Question 22

Bone turnover marker for formation

Answer 22

alk phos total and specific bone ALP

Question 23

Describe the two types of bone

Answer 23

Cortical bone: shaft of bones, strong,light weight exremities

Trabecular bone: axial skeleton, cross hairs/honeycomb - trabeculae strenght for weight

Question 24

Describe parathyroid disorders
hypercalemia

mod elevation

chronic mild

Answer 24

hypercalcemia elev in calcium above expected normal
lethargy/coma

Mod elev: personality changes, kidney stones

chronic mild: sympt free

Question 25

What is the most common cause of hypercalcemia

Answer 25

PHPT outpt setting

Question 26

Describe PHPT (primary hyperparathyroidism) causes? key feature autonom prod of? gender association? inc due to multicha?

Answer 26

Hypercalc key feature: autonomas overprod of PTH by single gland woman 3x more inc due to multichannel analyzers

Question 27

Diagnosis of PHPT elevation of serum.. biochem findings inc excretion of inc al dec 25 inc 1

Answer 27

elev serum calcium/improp norm or elev PTH biochem findings: hypercalc/hypophosph inc urine calc excretion inc alk phosph dec 25-OH-D inc 1,25 (OH) 2D

Question 28

Management of PHPT what surgery? inoperative....half life insid kid bone loss?

Answer 28

parathyroidectomy intraoperative PTH half life 5 min drops rapidly insidious onset kidney stones 20-30% bone loss cortical > trabular bone

Question 29

Secondary Hyperparathyroid causes? low complete rise in? low c/p inc al hypo deficiency?

Answer 29

hypercalcemia - low blood calcium complete rise in PTH low calc/phosph inc alk phos hypocalc/phoph VIT D deficiency

Question 30

2nd/3rd HPT in renal failure what has a central role? what causes what changes....? failure to excrete.. proportional to?

Answer 30

kidney central roll CKD causes bone/skeletal changes kidney fails to excrete phosph (impaired Vit D) bone changes proportional to severity

Question 31

What differentiates 2nd/3rd HPT in renal failure sustained? trans... CKD reduces increases PTH?

Answer 31

sustained hypercalcemia some pts delevope transient hypercal CKD reduced urine phosph excret inc blood phosph PTH increased

Question 32

FHH familial hypocalcemia/hypercalcemia benign mutation to ..production and elevated....are? results in?

Answer 32

benign germline mutation CSR - upsets PTH production and calcium elevated not prognostic results in stable/mild hypercalcemia since birth

Question 33

Clinical features: of FHH familial hypocalcemia/hypercalcemia increased c inc m inc pt whats <100mg mutant end orgn... surgery?

Answer 33

Inc serum calcium inc serum magnesium inc PTH urine calc <100mg mutant CSR end org dysfunction not common NO SURGERY

Question 34

Describe Hyperthyrodism inc b/h PTH levels? disease state? what can cause hyperparathyroidism? hyper...?

Answer 34

inc bone reabsorbtion/hypercalcemia PTH dec addisons disease - low PTH steroid replacement HCTZ/lithium cause hyperthyroidism hypervitaminosis

Question 35

Describe PTH rp (parathryoid related protein) secreted by? similar to? receptors? healthy humans? lactation?

Answer 35

substance secreted by cancer struct similar to PTH/funct features same receptors healthy human levels should be low/none normal lactation can cause PTH rp

Question 36

Hypercalcemia due to PTHrp is not due to what root cause? secretion not reg by? PTHrp cant facilitate?

Answer 36

cancer secreation not regulated by very high BP PTH rp cant facilitate renal hydroxylation of 25 VIT D

Question 37

Hypoparathyroidism inad... common causes?

Answer 37

inadequate parathyroid gland function common causes: neck surgery - thyroidectomy accidental gland removal damage to glands in surgert

Question 38

Auto immune destruction in hypothyroidism

Answer 38

Type 1 diabetes hashimotos addisons malignant deficiencies

Question 39

Pseudohypoparathyroidism inherit ...lack of intestinal..

Answer 39

inherited disorder lack of PTH response intenstinal disorders result in malabsorb of calc/VIT D

Question 40

Rickets

Answer 40

before epith plate closure in children

Question 41

Osteomalacia

Answer 41

minerilization in adults

Question 42

Osteoporosis what type of bones? prevelence? malform/reab ratio? risk of? diseases?

Answer 42

porous bones in adults most prevelent bone disease in adults bone malformation/excessive reab 4:1 F:M hip fractures cushings disease