Calcium Phosphate Flashcards Preview

Med 1 Endo > Calcium Phosphate > Flashcards

Flashcards in Calcium Phosphate Deck (87)
Loading flashcards...
1

How much of serum calcium is bound to a protein?

45%

2

What protein is calcium most commonly bound to?

Albumin

3

Because albumin levels will alter the serum calcium levels, in order to measure ionized Calcium effectively, one must

Correct for Calcium

0.8 * (4.0 - Pt's Albumin) + Serum Calcium

4

Alkalosis is indicated by what in reference to calcium?

Increased binding to albumin

5

Acidosis is indicated by what in reference to calcium?

Decreased binding to albumin

6

Calcium is regulated by

Parathyroid Hormone (PTH)
Vitamin D

7

Negative inhibition can be caused by acting what receptor?

Calcium Sensing Receptor (CaSR) to stop release of PTH

8

Where are the Calcium Sensing Receptors?

Parathyroid Gland

9

By inhibiting the release of PTH, what will happen in the kidneys?

Calcium will be excreted due to decreased Calcium reabsorption

10

PTH does what to the kidneys?

1. Increases Calcium Reabsorption
2. Increases Phosphate Excretion
3. Activates Vitamin D

11

What triggers PTH release?

Low blood calcium detected by the Parathyroid

12

Where are the parathyroids located?

Snake eyes on the thyroid gland (4)

13

When PTH is released, it affects which two things directly?

1. Bones
2. Kidneys

14

When Vitamin D is activated by the Kidney, it will affect what organ?

Small Intestine

15

Vitamin D causes what to happen in the Small Intestine?

Increases absorption of calcium from the diet

16

When PTH acts on the Bone, what does it do?

Stimulates osteoCLAST activity
-- Bone is resorbed which releases calcium into the blood stream

17

The overall affect of PTH release is to?

Increase Serum Calcium

18

High levels of Calcium in the blood will do what to the thyroid gland?

Stimulate to release Calcitonin

19

When Calcitonin is released from the thyroid (due to high Ca2+ levels in the blood), what happens?

Calcitonin will inhibit osteoclasts.

This will decrease blood Calcium levels.

20

When there is a decreased Calcium level in the blood, this will stimulate what to do what?

Stimulate the Parathyroid Gland to release more PTH

21

What in the parathyroid released PTH?

Chief cells

22

What is the form of Vitamin D released from the kidneys by PTH activation that acts on the Small intestines to increase dietary calcium absorption?

Calcitriol

23

Increased blood calcium can cause what to the bone?

Calcification

24

Common Symptoms with Hypercalcemia

1. Dehydration
2. Anorexia/Weight Loss
3. Pruritus
4. Fatigue
5. Weakness
6. Hypotonia (low muscle tone)
7. Myopathy (proximal)
8. Mental status change
9. Seizure/Coma
10. Bradycardia
11. Atrial or Ventricular Arrhythmia
12. Nausea Vomiting Constipation
13. Ileus
14. Pancreatitis
15. Dyspepsia
16. Polyuria
17. Nephrocalcinosis

25

Two broad causes of Hypercalcemia

1. PTH Dependent
2. PTH Independent

26

PTH Dependent causes of Hypercalcemia could be due to?

1. Primary Hyperparathyroidism (ademona, 4 gland hyperplasia)
2. Familial Hypocalciuric hypocalcemia
3. Tertiary Hyperparathyroidism

27

PTH Independent causes of Hypercalcemia could be due to?

1. Malignancy (direct bone invasion, PTH rp release, Increased 1,25 Vitamin D synthesis)
2. Vitamin D Intoxication
3. Medications (thiazides, Lithium)
4. Granulomatous Dz
5. Hyperthyroidism
6. Vitamin A intoxication

28

Granulomatous Diseases

TB
Fungal Diseases
Sarcoidosis

29

Granulomatous Diseases & Vitamin D Intoxication cause

Increased 1,25 Vitamin D, which causes increased absorption of Ca2+ from the intestines

30

Thiazides and Familial Hypocalcemic Hypercalcemia cause

Increased reabsorption of Ca2+ in the kidneys