Parathryoid (HYPERcalcemia) Flashcards Preview

Endocrine > Parathryoid (HYPERcalcemia) > Flashcards

Flashcards in Parathryoid (HYPERcalcemia) Deck (27):
1

Loss of function seen in FHH is 

Psuedo-hypoparathyroidism

2

ADH acts on CaSR of the parathyroid cell to cause release of:

Parathryoid hormone

3

What can we use to treate severe hyperparathyroidism

A calcimimetic; cinacalcet

4

Excess PTH leads to excess Calcium...  what are symptoms of excess Ca?

• Fatigue, weakness • Nausea, vomiting, constipation • Anorexia • Polyuria, polydipsia • Dehydration • Memory impairment • Drowsiness, confusion, coma

5

Hypercalcemia is caused by an increase in PTH secretion, we see this in:

Primary hyperparathyroidism (usually a parathyroid adenoma)

6

Hypercalcemia results in a suppression of PTH secretion; what are some causes

Vitamin D intoxication, Hypercalcemia of malignancy (caused by PTHrp)

7

Hypercalcemia that is PTH Dependent is:

Primary hyperparathyroidism (PHPT)

8

Some causes of Primary hyperPT

–Sporadic (single and multiple gland disease, carcinoma) – Multiple endocrine neoplasias (MENs) – will be discussed in a subsequent session – Hyperparathyroidism jaw tumor syndrome

9

HOw do PTH secreating cells respond to high Ca++ in Primary HyperPT?

Decreased sensitivity of PTH-secreting cells to inhibition by plasma Ca++ and 

Increased or “inappropriately not suppressed” serum PTH levels.

10

What kind of Ca++ and Phosphate levels do we see in pts with Primary HyperPT?

Hypercalcemia (due to effects of PTH on bone resorption, calcium reabsorption, and increase in 1,25(OH)2D production in the kidneys).

Hypophosphatemia due to phosphaturic effects of PTH in the proximal tubules.

11

Some patients with PHPT are hypercalciuric despite PTHmediated increase in Ca++ reabsorption in the distal tubules because 

the filtered load of calcium exceeds the Tm for reabsorption.

12

Causes of Hypercalcemia PTH DEPENDENT

• Familial isolated hyperparathyroidism

• Familial hypocalciuric hypercalcemia (FHH)

• Ectopic PTH – RARE!

13

• Asymptomatic, modest, lifelong hypercalcemia

Hypocalciuria

• PTH not suppressed

• Autosomal dominant

• Surgery not indicated

Familial Hypocalciuric Hypercalcemia (FHH)

14

Mutation seen in FHH

- CaSR (chromosome 3) (~2/3)

• Codominant - neonatal severe hyperparathyroidism

15

Two findings in the bone you see with severe Primary Hyper Parathyroidism

Hyperpara osteitis: fibrous tissue in bone

Brown tumor: see lytic lesion anf ofteh multinucleated osteoclasts

16

What does a scanning EM of the bone look like in pt with PHPT

see cortical bone is thinned out, controverys over wheter trabeculated bone is spared or not

17

Causes of PTH-INDEPENDent Hypercalcemia

Malignancy

Calcitiro mediated; granulmos or inflammation

Yperthyroidism

milk alkali or calcium alkali syndrome

18

Has – N-terminal homology with PTH, use in assays, found in high conc in normal tissue and key for fetal development

Parathyroid-Hormone-Related Peptide (PTHrP)

19

Calcitriol (1,25[OH]2D)-Mediated Hypercalcemia can be caused by:

sarciod and lympohma

20

Your pt has elevated Ca+ levels, what test do you order next?

Order PTH

21

Hypercalcemic pt had PTH labs done, they have elevated PTH, what is our next step?

Most likely dx – primary hyperparathyroidism

Measure 24 hour urine calcium & creatinine to rule out FHH 

22

A primary process causing too much____ (primary hyperparathyroidism) will cause hypercalcemia [increased bone resorption and increased production of 1,25(OH)2D)].

PTH

23

A process which raises the serum calcium independent of PTH (for example a tumor producing PTH related protein or lytic bone lesions) will suppress ____

PTH.

24

Pt has Hypercalcemia and LOW PTH, what could be going on?

PTH independent HyperPT;

excess 1,25-D suggets cancer, sarcoid or hyperthyroidism

25

How do you tx pt with Hypercalcemia?

IV fluids; normal saline

Loop diuretics; furosemide but waith till AFTER pt is rehydrated

Calcitonin

Bisphosphonates

26

used to tx hypercalcemia, potently inhibit osteoclastic bone resorption.

Bisphosphonates

27

A drug to tx hypercalcemia: see a rapid reduction in Ca2+ can occur. “Escape" from the hormone commonly occurs within several days. Calcitonin can lower serum calcium by 1-2 mg/dL

Calcitonin