Flashcards in Calcium Phosphate Deck (87)
How much of serum calcium is bound to a protein?
What protein is calcium most commonly bound to?
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
Alkalosis is indicated by what in reference to calcium?
Increased binding to albumin
Acidosis is indicated by what in reference to calcium?
Decreased binding to albumin
Calcium is regulated by
Parathyroid Hormone (PTH)
Negative inhibition can be caused by acting what receptor?
Calcium Sensing Receptor (CaSR) to stop release of PTH
Where are the Calcium Sensing Receptors?
By inhibiting the release of PTH, what will happen in the kidneys?
Calcium will be excreted due to decreased Calcium reabsorption
PTH does what to the kidneys?
1. Increases Calcium Reabsorption
2. Increases Phosphate Excretion
3. Activates Vitamin D
What triggers PTH release?
Low blood calcium detected by the Parathyroid
Where are the parathyroids located?
Snake eyes on the thyroid gland (4)
When PTH is released, it affects which two things directly?
When Vitamin D is activated by the Kidney, it will affect what organ?
Vitamin D causes what to happen in the Small Intestine?
Increases absorption of calcium from the diet
When PTH acts on the Bone, what does it do?
Stimulates osteoCLAST activity
-- Bone is resorbed which releases calcium into the blood stream
The overall affect of PTH release is to?
Increase Serum Calcium
High levels of Calcium in the blood will do what to the thyroid gland?
Stimulate to release Calcitonin
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.
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
What in the parathyroid released PTH?
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?
Increased blood calcium can cause what to the bone?
Common Symptoms with Hypercalcemia
2. Anorexia/Weight Loss
6. Hypotonia (low muscle tone)
7. Myopathy (proximal)
8. Mental status change
11. Atrial or Ventricular Arrhythmia
12. Nausea Vomiting Constipation
Two broad causes of Hypercalcemia
1. PTH Dependent
2. PTH Independent
PTH Dependent causes of Hypercalcemia could be due to?
1. Primary Hyperparathyroidism (ademona, 4 gland hyperplasia)
2. Familial Hypocalciuric hypocalcemia
3. Tertiary Hyperparathyroidism
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
6. Vitamin A intoxication
Granulomatous Diseases & Vitamin D Intoxication cause
Increased 1,25 Vitamin D, which causes increased absorption of Ca2+ from the intestines