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