Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

SEM 5: SAM 1 > Parathyroid and Calcium Metabolism > Flashcards

Parathyroid and Calcium Metabolism Flashcards

1
Q

What hormone is responsible for the number of receptors in the intestine for absorption of calcium?

A

Vit D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How many parathyroid glands are present in a patient?

A

4, 2 on each thyroid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the principle cell present in the parathyroid gland?

A

Chief cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How does PTH act on the bone?

A
  • Binds to osteoblasts
  • Increases activity of osteoclasts to breakdown and release Ca and phosphorus
  • Decreases bone density
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How does PTH act on the kidney?

A
  • Blocks reabsorption of phosphorus
  • Increased excretion of phosphorus
  • Increases calcium absorption from tubules
  • Activates 1-alpha hydroxyase which stimulates production of Vit D
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the feedback loop that regulates PTH secretion

A

↓ Ca = ↑ PTH
↑ Ca = ↓ PTH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How does Vitamin D effect calcium levels?

A
  • Facilitates intestinal absorption of calcium in the gut
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the actions of calcitonin?

A
  • Reduces blood calcium
  • Suppresses reabsorption of Ca+ and phosphorus in kidney, increased excretion
  • Inhibits bone resorption by inhibiting osteoclasts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How does hypercalcemia affect kidney function?

A

Interferes with ADH, can’t concentrate urine, isosthenuric and PU/PD

(nephrogenic diabetes insipidus)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the clinical side effects of hypercalcemia?

A
  • PU/PD
  • Dystrophic calcification in organs
  • Cardiac dysfunction
  • Inappetence, V/D
  • Constipation in cats
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

DDx for Hypercalcemia?

A

DRAGONSHIT

  1. Vit D toxicity
  2. Renal failure
  3. Addisons
  4. Granulomatous dz
  5. Osteolysis (fracture, multiple myeloma)
  6. Neoplasia
  7. Spurious
  8. HyperPTH
  9. Idiopathic
  10. Toxins (ethylene glycol)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What neoplasias can cause hypercalcemia?

A
  • Anal sac adenocarcinoma
  • Mammary carcinoma
  • Lymphoma
  • Multiple myeloma (from osteolysis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How can ultrasound help diagnose hyperPTH?

A

If 1 parathyroid is overreactive, other parathyroid glands are usually small and atrophied

  • Overactive parathyroid may be large or normal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the causes of secondary hyperPTH, and what would you expect PTH and Calcium levels to be in this case?

A
  • Nutritional deficient Ca+ diet
  • Renal dz (loosing too much Ca+)

Secondary hyperPTH: will show ↑ PTH and ↓ Ca

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the causes of primary hyperPTH, and what would you expect PTH and Calcium levels to be in this case?

A

Idiopathic hyperplasia of the parathyroid gland

Primary hyperPTH: will show ↑ PTH and ↑ Ca

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What breeds are associated with primary HyperPTH?

A
  • Keeshond
  • GSD
  • Norwegian elkhound
  • Siamese cats
17
Q

What is the emergency treatment of hypercalcemia?

A
  • Diuresis (fluids) to flush out Ca+
  • Furosemide (once hydrated)
  • Glucocorticoids (decreases Ca+ reabsorption, BUT don’t give if neoplasia can’t be ruled out)
  • Calcitonin (short term only, eventually body makes AutoAb to salmon calcitonin)
  • Bisphosphates (good for chronic conditions and multiple myeloma… binds to bone and inhibits osteoclasts)
18
Q

How are bisphosphates beneficial in treating hypercalcemia?

A

Binds to bone and inhibits osteoclasts, has a long half life

Good for chronic conditions and multiple myeloma

19
Q

What are the disadvantages of using bisphosphates to treat hypercalcemia?

A
  • PO can cause esophagitis
  • Injection can cause AKD
  • Given on empty stomach
  • Spontaneous fractures in cats
20
Q

Why is calcitonin only recommended for acute treatment of hypercalcemia?

A

Usually using salmon calcitonin… body will eventually make AutoAb against it… not for chronic use

21
Q

What are the causes of hypoparathyroidism?

A

Primary - lymphocytic parathyroiditis

Iatrogenic - complication of thyroidectomy

22
Q

What breeds are associated with Hypoparathyroidism?

A
  • Toy poodles
  • Mini schnauzers
  • Labs
  • GSD
  • Terriers
23
Q

What are clinical signs of hypoparathyroidism?

A

CS due to hypocalcemia

  • Seizures
  • Twitching
  • Ataxia
  • Facial rubbing, biting at feet (Cats > dogs)
  • Arrhythmias
  • Pyrexia (fever) from tremors
24
Q

What are the PTH, Calcium and phosphorus levels in a hypoparathyroid patient?

A

↓ PTH, ↓ Ca, ↑ phosphorus

25
Q

What is the emergency treatment of hypocalcemia?

A
  • 10% calcium gluconate slowly IV, monitor ECG
  • Continue for a couple days until PO drug takes effect
  • Monitor temp
    Maintenance:
  • PO calcium
  • PO Vit D3

SEM 5: SAM 1 (35 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions