Lecture 5 - Parathyroid/calcium disorders

Question 1

PTH is released in response to low serum ____ or high serum ____

Answer 1

calcium, phosphate

Question 2

PTH:
increases reabs of calcium in the _____;
increases secretion of phosphate in the _____;
increases production of Vit D by stimulating ____ in the _____;
increases bone resorption of ….

Answer 2

DCT;
PCT;
1 alpha hydroxylase, PCT;
Ca and PO4

Question 3

calcitriol causes increased release of ____ which decreases bone formation.
calcitriol also increases calcium and phosphate reabsorption from the ____ and _____

Answer 3

FGF23;

GI, kidney

Question 4

calcium:

increase in concentration causes a _____ in refractoriness of stimulation of neurons and muscle cells

Answer 4

increase

causing coma, muscular weakness

Question 5

decrease in calcium leads to _____ in neuromuscular excitability–>translates into _____ and ____

Answer 5

increase;

tetany, convulsions

Question 6

what is the name of the calcium salt that is the major structural cation?

Answer 6

hydroxyapatite

Question 7

calcium:

alkalosis causes a _____ in binding affinity to albumin, ____ calcium levels and causing _____

Answer 7

increase;
lowering;
tetany, parasthesia

Question 8

calcium levels also decrease with decreased levels of serum ____ or increased levels of ____

Answer 8

albumin, phosphate

Question 9

hypocalcemia:
\_\_\_\_;
chvostek sign = 
trousseau sign =
in the heart: \_\_\_\_\_\_

Answer 9

tetany;
tap facial nerve–>contract muscle;
occlude brachial artery–>carpal spasm;
prolonged QT (risk of torsades)

Question 10

hypoparathyroidism: during ____ surgery, autoimmune destruction, ____ syndrome

Answer 10

thyroid;

digeorge

Question 11

digeorge syndrome:

CATCH 22

Answer 11

C = cleft palate
A = abnormal facies
T = thymic aplasia --> T cell deficiency
C = cardiac defects
H = hypo calcemia

22q11 deletion

Question 12

according to FA, normal serum calcium is between ____ and ____

Answer 12

8.4-10.2 mg/dL

Question 13

hypercalcemia symtpoms:

_____, ____, _____, _____, and ____ overtones

Answer 13

stones (nephrolithiaisis)
bones (bone pain)
groans (abdominal pain, constipation)
thrones (increased urinary frequency)
psychiatric (anxiety, impaired concentration)

Question 14

primary hyperparathyroidism:
usually due to ___ or ____;
in addition to the hypercalcemia symptoms mentioned, can have acute ____, ______ ulcers, nephrocalcinosis

Answer 14

adenoma, hyperplasia;
pancreatitis;
peptic

Question 15

familial hypocalciuric hypercalcemia:
due to defective ______ in multiple tissues. ____ than normal Calcium is required to suppress PTH =
mild ____ and hypo _____ with ____ PTH levels

Answer 15

Ca sensing receptors;
greater;
hypercalcemia, hypocalcuria;
normal to increased

Question 16

diuretics:
_____ diuretics decrease reabsorption –> hypocalcemia;
_____ diuretics increase reabsorption

Answer 16

loop;

thiazide

Question 17

hypercalcemia of malignancy can be due to ____ or _____

Answer 17

bony metastases;

PTHrp

Question 18

after confirming clinical hypercalcemia, what should you check next?

Answer 18

intact PTH
( if increased, primary HPTH or familial)

Question 19

with chronic renal failure:

___calcemia, ____phosphatemia, failure of _____ –> __ PTH levels

Answer 19

hypo, hyper;
vitamin D hydroxylation;
increased

Question 20

criteria for surgery of primary hyperPTH:
clinical manifestations of \_\_.
age \_\_\_ than 50 years;
creastinine clearance less than \_\_\_\_
current or past kidney \_\_\_

Answer 20

hypercalcemia;
less than;
60;
stones

Question 21

Vitamin D deficiency causes a ____ in urinary phosphate excretion

Answer 21

increase

Question 22

symptoms of hypophosphatemia:
bone ____, ____ levels fall causing an increase in Hb affinity = tissue ____;
encepalopathy, rhabdomyolysis

Answer 22

loss;
2,3 DPG;
hypoxia

Question 23

hyperphosphatemia:
renal ____, metastatic _____, ___calcemia

asociated with tumor lysis, rhabdomyolysis
hypo PTH

Answer 23

stones, calcification, hypo

Question 24

osteomalacia:
decreased VIT D –> ____ serum Ca –> ___ PTH –> ____ serum PO4

____ ALP

Answer 24

decreased, increased, decreased;

increased

Question 25

``` rickets symptoms: genu ____ (bow legs), bead-like _______ (rachitic rosary), _____ (Soft skull), frontal bossing ```

Answer 25

varum; costochondral junction; craniotabes

Question 26

_____ are characteristic radiological findings in osteomalacia. they are ____ of femoral neck/nearby areas

Answer 26

looser's zones; | pseudofractures

Question 27

chronic kidney disease: see ____ Ca absorption and/or ____ phosphate absorption . renal failure causes decreased ____ levels --> excessive levels of _____

Answer 27

decreased, increased; vitamin D; PTH (secondary HPTH)

Question 28

______ is due to high bone turnover caused by hypert PTH. causes ____ bone spaces

Answer 28

osteitis fibrosa cystica; | cystic

Question 29

what is tertiary hyper PTH?

Answer 29

autonomous/refractory hyper PTH resulting from CKD.

Question 30

3 stages of paget disease:

Answer 30

``` osteoclastic overactivation (lytic) mixed osteoblasts and osteoclasts osteoblast overactivation (sclerotic) ```

Question 31

``` paget's: localized or widespread bone disorder? associated with increased _____ size. ____ loss from foramen narrowing. ____ ALP ```

Answer 31

localized; hat; hearing; increased

Question 32

serum Vit D levels should be greater than ___ ng/mL

Answer 32

32