Exam 3 Parathyroid Function & Calcium Regulation

Name the 3 regulators of Calcium
Vitamin D
PTH
Calcitonin
Does PTH raise or lower Calcium levels?
Raise
Does Calcitonin raise or lower Calcium levels?
Lower
True or False:
Calcium is involved in the neuromuscular system; it initiates muscle contraction
True
Which organ converts Vit D3 to 25-hydroyl Vitamin D
Liver
Which organ converts 25-hydroyl Vitamin D to the active form under the control of PTH?
Kidneys
What does Active Vitamin D target the intestines for?
Absorption of Calcium
True or False:
There are 4 parathyroid glands embedded in or near the thyroid gland
True
Does low concentration or high concentration of Calcium trigger the release of PTH?
Low Concentration
Does low concentration or high concentration of Calcium trigger the release of Calcitonin?
High Concentration
True or False:
When there is high calcium and calcitonin is released, calcium is Excreted into the Urine
True
When there is high calcium and calcitonin is released, calcium is excreted into the urin. What happens to the plasma calcium levels?
Lower
What does HYPERcalcemia lead to?
Kidney stones
GI problems/anorexia
CNS symptoms
Bone demineralization
What is the #1 cause of HYPERcalcemia?
Hyperparathyroidism
Other than Hyperparathyroidism, what are 2 other causes of HYPERcalcemia?
Multiple Myeloma
Drugs, inherited
In general, what happens to PO4 when Calcium increases?
Decreases
In general, what happens to PO4 when Calcium decreases?
Increases
High PO4 in junk food and soda may cause plasma Calcium levels to be what?
Lower
What are the following symptoms associated with:
Tetany
Heart dysfunction, confusion, bone fractures
HYPOcalcemia
What are 6 causes of HYPOcalcemia?
Parathyroid dysfunction
Insufficient Vitamin D
Insufficient dietary Calcium
GI malabsorption
Kidney disease
Drugs
What is the cause of Primary HYPERparathyroidism?
Parathyroid tumor
What does the Parathyroid tumor stimulate in Primary HYPERparathyroidism?
Excess PTH Production
What causes excess Calcium to be sucked from bone, kidneys, and intestines?
Excess PTH Production
What are the following symptoms associated with:
Renal stones, renal damage, GI problems, CNS symptoms, bone fractures
Primary HYPERparathyroidism
What is the #1 cause of elevated Calcium?
Primary HYPERparathyroidism – Parathyroid tumor
The following is seen in what kind of HYPERparathyroidism?
Increased Calcium
Decreased PO4
Increased PTH
Increased ALP
Primary HYPERparathyroidism – Parathyroid tumor
The following is seen in what kind of HYPERparathyroidism?
Decreased Calcium
Increased PO4
Increased PTH
Increased ALP
Secondary HYPERparathyroidism – Vitamin D Deficiency or Renal Failure
True or False:
In secondary hyperparathyroidism, decreased absorption of Calcium OR decreased tubular retention of Calcium turns on PTH
True
True or False:
In secondary hyperparathyroidism, Plasma Calcium levels remain LOW despite HIGH levels of PTH
True
What does Secondary HYPERparathyroidism cause in kids?
Rickets
What does Secondary HYPERparathyroidism cause in adults?
Osteomalacia
What are the 2 most common causes of HYPOparathyroidism?
Accidental injury to parathyroid glands
Autoimmune disease
True or False:
In HYPOparathyroidism, since PTH production is hampered, Calcium levels remain low
True
True or False:
Tetany may develop due to Hypoparathyroidism & Hypocalcemia
True
The following is seen in which disease/disorder:
Decreased PTH
Decreased Calcium
Increased PO4
HYPOparathyroidism
What will be increased in All of the following:
Primary Hyperparathyroidism, Secondary Hyperparathyroidism, & Hypoparathyroidism
ALP
Intraoperative PTH – levels are measured during surgery to determine extent and success of what?
Tumor removal
Successful removal of hypersecreting tissue is indicated by at least a _____ decrease in the blood PTH level within 10 minutes after resection.
50%
Successful removal of hypersecreting tissue is indicated by at least a 50% decrease in the blood PTH level within how many minutes after resection.
10 minutes
What is associated with the following:
Breakdown product of bone cartilage
N-Telopeptide (NTx)
What does high levels of NTx in urine indicate?
Excessive bone turnover
What are high levels of NTx consistent with?
Osteoporosis
What is Bone specific ALP?
Ostase
What is used to monitor the response to osteoporosis therapy?
Ostase
What substance does parathyroid hormone regulate in plasma?
Calcium
In order to raise Calcium, which two organs does PTH target?
Bbone
Kidneys
In order to raise Calcium, what does PTH cause to happen?
Bone – release/secrete Calcium
Kidneys – Make Active Vitamin D and reabsorb more Calcium
What is the counter-regulatory hormone that serves to lower this substance?
Calcitonin
For each of the following disorders, indicate if results will be increased, decreased, or normal:
Hyperparathyroidism
Calcium – Increased
PO4 – Decreased
PTH – Increased
ALP – Increased
For each of the following disorders, indicate if results will be increased, decreased, or normal:
Vitamin D Deficiency
Calcium – Decreased
PO4 – Increased
PTH – Increased
ALP – Increased