Pathophysiology: Ca and PTH

Question 1

What are the fast PTH responses? Slow?

Answer 1

Fast: bone and renal resorption
Slow: Intestinal Vit D, renal effect takes time

Question 2

What senses Ca in the Parathyroid?

Answer 2

CaSR

Question 3

What are the top three causes of HyperPTH?

Answer 3

PT Adenoma
Familial HypocalURIA HypercalcEMIA
Lithium or HCTZ meds
<1% PT carcinoma

Question 4

What are the PTH dependent causes of high Ca?

Answer 4

HyperPTH, Familial HH, Li/HCTZ

Question 5

What are the PTH independent causes of high Ca?

Answer 5

Tumor
Granulomatous disease
Multiple myeloma

Question 6

Waht is the treatment of acute high Ca?

Answer 6

Saline (to correct polyuria)

Furosemide (to draw off Ca)

Question 7

What is the presentation of PT Adenoma? What do you to?

Answer 7

Stones: pain while peeing
Groans: constipation/GI pain
Bones: fractures?

Measure albumin, PTH

Question 8

What do you do to differentiate FHH and PT adenoma?

Answer 8

24 hour urine:
PTadenoma: high Ca
FHH: low Ca

Question 9

What is the defect in FHH?

Answer 9

CaSR, AD mutation

decreased Ca sensation removes negative feedback of PTH increasing Ca

Question 10

What is typical 24 hr urine in FHH?

Answer 10

<50-100

Question 11

What is 3* HyperPTH?

Answer 11

End stage renal disease, post kidney transplant causes Ca wasting in urine

Question 12

What cancers make Ca higher?

Answer 12

Small cell lung
Breast
*Mets, cytokines, multiple myeloma

Question 13

What do labs for cancer high Ca look like?

Answer 13

HIGH Ca, low PTH (PTHrelated peptide is made, NOT PTH!)

Question 14

What causes increased Ca in granulomatous disease?

Answer 14

1a Hydroxylase–>increased VitD3

Question 15

How do you tell difference between gland hyperplasia and adenoma?

Answer 15

Adenoma: one site
Hyperplasia: whole gland

Question 16

What is 2* hyperPTH?

Answer 16

Renal disease: HIGH PTH! but it doesnt work…

low Ca, high PO4, low VitD3

Question 17

What are causes of low Ca?

Answer 17

Albrights hereditary osteodystrophy
MEN syndromes

*acute pancreatitis, transfusion, tumor lysis, rhabdomyolysis, sepsis, bisphosphonates, hungry bone syndrome

Question 18

DDx for low Ca?

Answer 18

PTH low? HypoPTH, Mg deficiency, PO4 excess

PTH high? Vit deficiency, renal failure, PTH/VitD resistance

Question 19

How does low Ca present?

Answer 19

Agitation
Hyperreflexia
Convulsions
QT prolongation
Hyperextension

Question 20

Tx for acute low Ca?

Answer 20

Correct Mg

Calcium gluconate

Question 21

Tx for chronic low Ca?

Answer 21

Oral Ca
Vit D if PTH still present
HCTZ

Question 22

What is defect in PseudohypoPTH? What do they look like?

Answer 22

Gsa subunit mutation, cannot stimulate PTH via cAMP pathway

*Short stature, round face, “short 5th metacarpal”, obesity

Question 23

MEN definition?

Answer 23

Multiple Endocrine Neoplasia:

Multiple tumors, 1 patient

Question 24

When do MEN 1 patients get pancreatic cancer?

Answer 24

25-35, pituitary by 38, 1* HPT by 40

Question 25

MEN 1 includes?

Answer 25

``` Defect in MENIN: TSG MEN1 Chromosome 11 "PPP" Pancreas: hypoglycemia Parathyroid: high Ca, stones Pituitary: galactorea, weight gain, diarrhea ```

Question 26

Patient presents with polyuria, pain in peeing and lethargy, found passing out and says to have grown breasts and gained weight:

Answer 26

MEN1: PPP

Question 27

MEN 2a?

Answer 27

``` RET : RTK oncogene Chromosome 10 "TPP" Thyroid: medulary Pheochromocytoma Parathyroid ```

Question 28

MEN 2b?

Answer 28

``` RET/Cr.10-single AA! TPMM Thyroid: medulary Pheochromocytoma Marfan-looking Mucosal Neuromas ```

Question 29

Especially tall patient has lump in throat and bumps on tongue?

Answer 29

MEN2b

Question 30

Large round patient has kidney stones and is bugging out eyes....

Answer 30

MEN2a (terrible presentation... sorry)

Question 31

What branchial pouch do top 2 parathyroids develop from?

Answer 31

4th

Question 32

What branchial pouch do bottom 2 parathyroids develop from?

Answer 32

3rd (with Thymus!)