Parathyroid Flashcards Preview

Endocrine > Parathyroid > Flashcards

Flashcards in Parathyroid Deck (27):
1

Chotzeks sign

 

Trausseau's sign ypocacemic tetany

Chotzeks sign - tap on facial nerves > corner of mouth twitch

 

Trausseau's sign - BP cuff >20mmHg above systolic > clawed spasm

 

 

2

in PTH resistance, serum phosphorus is

high normal

2

Excess/deficiency of FGF23 can cause...

Excess: hypophosphatemia

imparied bone mineralization (genetic ricketts, tumor-induced osteomalcia)

 

Decreased - hyperphosphatemia and tumor calcinosis (calcified masses)

3

FGF423 action

made by osteocytes

increases urinary phosphate excretion

decreases renal production of 1,25(OH)2D

4

in hypoparathyroidism

Serum Ca

Serum PO-

Intact PTH

25-OHD-

 

Serum Ca - low

Serum PO4 - high/normal

Intact PTH = low normal

25-OHD3 -normal

4

in pseudohypoparathyroidism

 

Serum Ca

Serum PO4 -

Intact PTH

25-OHD3 -

 

Serum Ca low

Serum PO4 -high normal

Intact PTH high

25-OHD3 - normal

6

most common cause of PTH INdependent hypercalcemia 

cancer and granulomatous diseases

6

primary hypocalcemia caused by

 

secondary

deficiency in PTH secretion

 

secondary - renal failure - cannot produced adequate 1,25(OH)D)

malabsorption

vitamin D deficiency

7

highly regulated step 1-hydroxylating 25(OH)D to 1,25(OH)D is stimualted by

PTH

8

in PTH independent hypercalcemia, PTH is usually

supressed

8

pseudohypoparathyroidism = 

resistnace to PTH

10

Treatment of Hypercalcemia

IV fluids - normal saline

Loop diuretics (Furosemide) (augemnt Ca2 exretion)

Calcitonin - rapid reduction in Ca2 (escape occurs in several days)

Bisphosphonates - inhibit osteoclastic boen reabsorption

11

Familial hypocalciuric hypercalemia findings

asymptomatic lifelong hyercalcemia

hypocalciuria

PTH not surpressed

13

in secondary hyperparathrydoism

 

Serum Ca

Serum PO4 -

Intact PTH

25-OHD3 -

 

Serum Ca - low

Serum PO4 - low normal

Intact PTH - High

25-OHD3 - low 

14

in magnesium depletion

 

Serum Ca

Serum PO4 -

Intact PTH

25-OHD3 -

 

Serum Ca - low

Serum PO4 -normal 

Intact PTH - low normal 

25-OHD3 - N

15

Familial hypocalciuric hypercalcemia genetics 

AD

FHH1 most familes (CaSR on chromosome 3)

not all FHH have CaSR mutations

16

PTH-indepednet hypercalcemia etiology

Malignancy - bone metastes, PTH-related protein, osteoclast activating factors, unregulated calcitriol production, ectopic PTH

Calcitriol mediated granulomatous, inflammatory

Hyperthyroidism

Milk-alkali syndrome or calcium-alakli syndrome (CaCO3 over dose)

imobilization

 

17

deactivates 25D

24-hydroxylase

18

symtpoms hypocalcemia

Neuromusuclar iratability - parathesias, muscle cramps, tetany, 

lowered seizure threshold

mental status changes

prolonged QT, arrhythmias, CHF

basal ganglia calcification

cataracts

Chvosteks and trousseasus sign

19

treatment of hypocalcemia

IV calcium gluconate (initially)

Vitamin D2, D3, calcitriol

21

most common cause of PTH dependent hypercalcemia

hyperparathyroidism

22

2 underlying mechanisms of ECF volume contraction ion hypercacemia

Anorexia, nausea, vomiting

 

renal salt and water loss

23

in secondary hyperparathyroidism, serum phosphorus is

low normal (unless from renal failure, then it is low high)

24

skeletal morphology in primary hyperparathyroidism

BMD decreased preferentially at cortical sites

fractures increased

25

Calcimimetic (cinacalcet) can be used to treat

severe hyperparathyroidism

26

Calcitriol (1,25OH2D) mediated hypercalcemial =

 

found in:

non-renal/unregulated expression of 1-hydroxylase

 

sarcoid

lymphoma

tubercuolosis

27

findings in primary hyperparathyroidism

decreased sensitivity of PTH secreting cells to inhibition by Ca

increased/inappropriately not supresssed PTH

Hypercacelmia (bone resorption, calcium reabsorption, increase in 1,25D production in kidneys)

Hypophosphetemia - phosphaturic effects

some patients Hypercaciuric (filtered load exceeds Tm for reabsorption)