Calcium and Bone Disorders

Question 1

Normal PTH, high calcium suggests:

Answer 1

Primary hyperparathyroidism
or
Familial Hypocalciuric Hypercalcemia

Question 2

Name 5 causes of PTH independent hypercalcemia

Answer 2

Malignancy
Granulomatous disease
Vitamin A toxicity
VItamin D toxicity
Milk alkali syndrome

Question 3

Main defense against hypercalcemia

Answer 3

PTH suppression

Question 4

Phosphorus level in primary hyperparathyroidism

Answer 4

normal-low b/c increased PTH mediated renal excretion

Question 5

Best approach of treatment for primary hyperparathyroidism

Answer 5

Parathyroidectomy

Question 6

Describe the expected levels in primary hyperparathyroidism:
Ca:
PTH:
Phosphorus:

Answer 6

Ca: increased
PTH: increased
Phosphorus: low-normal

Question 7

If patient’s serum calcium is not too high, has osteoporosis and refuses to have parathyroidectomy to treat his primary hyperparathyroidism, you should treat with ____

Answer 7

bisphosphonate

Question 8

If patient’s serum calcium is very high and refuses to have parathyroidectomy to treat his primary hyperparathyroidism, you should treat with ____

Answer 8

Cinacalcet = calcimiertric

Mimics calcium → binds Ca sensing receptors (CaSR) on parathyroid tissue → decrease PTH secretion → decrease Ca level

Question 9

Cinacalcet (calcimiertric) treats all of the following except:
A. Severe secondary hyperparathyroidism
B. Hypercalcemia due to parathyroid carcinoma
C. Familial Hypocalciuric Hypercalcemia
D. Primary hyperparathyroidism

Answer 9

C

Question 10

Describe the expected levels in Familial Hypocalciuric Hypercalcemia
Ca:
PTH:
Urinary Ca:

Answer 10

Ca: mildly elevated
PTH: normal - slightly elevated
Urinary Ca: VERY low
Distinguishes FHH from primary hyperparathyroidism

Question 11

Name the disorder:

Inactivating mutation in gene of calcium-sensing receptor

Answer 11

Familial Hypocalciuric Hypercalcemia

Question 12

Which of the following is NOT a symptom of hypercalcemia?
A. Fatigue
B. Tetany
C. Bradycardia
D. HTN 
E. Polyuria

Answer 12

B. sign of HYPOcalcemia

Question 13

Describe the expected levels in Milk Alkali Syndrome:
Ca:
PTH:

Answer 13

Ca: increased
PTH: low

Normal PTH-rP, 25 OHD, 1,25 (OH)2D, Vitamin A, SPEP to rule out other PTH independent causes

Question 14

Acute therapy of PTH independent hypercalcemia

Answer 14

Fluids to induce natriuresis

Question 15

Intermediate therapy of PTH independent hypercalcemia

Answer 15

IV bisphosphnates:
Zoledronic acid
Pamidronate

Question 16

Describe the expected levels in PTH independent hypercalcemia:
Ca:
PTH:

Answer 16

Ca: high
PTH: low
Trying to unsuccessfully correct calcium b/c another process is driving calcium up

Question 17

Hypercalcemia of malignancy w/ PTHrP seen in (2)

Answer 17

Lung

Renal cell

Question 18

Hypercalcemia of malignancy w/ 1,25 (OH)2 vitamin D seen in (2)

Answer 18

Lymphoma

Leukemia

Question 19

Most common cause of hypercalcemia in hospitalized patients

Answer 19

Hypercalcemia of malignancy

Question 20

Describe the expected levels in hypoparathyroidism:
PTH:
Ca:
Urine Ca:
Phosphorus:

Answer 20

PTH: Low (Normal: should be high in low Ca)
Ca: Low
Urine Ca: High (PTH normally promotes renal calcium reabsorption)
Phosphorus: High (PTH normally promotes renal P excretion)

Question 21

Treatment of hypoparathyroidism

Answer 21

Calcium

Calcitriol (1,25 OH2D)

Question 22

Which of the following is NOT a symptom of hypocalcemia?
A. Parasthesia
B. Tetany
C. Confusion/fatigue/depression
D. QT shortening
E. Seizures

Answer 22

D. QT prolongation

Question 23

Inflating a blood pressure cuff to 20 mmHg above systolic blood pressure for 3 minutes inducing the Carpopedal spasm

Answer 23

Trousseau’s sign

Sign of hypocalcemia

Question 24

Elicited by tapping facial nerve → contraction of (contralateral/ipsilateral) facial muscles

Answer 24

Ipsilateral

Chvostek’s sign

Question 25

All of the following are treatments for hypoparathyroidism EXCEPT: A. Calcium B. Vitamin 25(OH)2D C. Human recombinant PTH

Answer 25

B. Vitamin 1,25(OH)2D: Must be active form b/c PTH not available to activate. A. IV if tetany. Oral otherwise C. Just approved. Not ideal.

Question 26

When you see hypocalcemia, check ___ to evaluate for cause.

Answer 26

PTH

Question 27

Low calcium, high PTH suggests (4)

Answer 27

Poor calcium intake Vitamin D deficiency PTH resistance: pseudohypoparathyroidism Vitamin D resistance

Question 28

``` Describe the expected lab values for Vitamin D deficiency: Ca: PO4: PTH: 25(OH)D: 1,25 (OH)2D: ```

Answer 28

``` Ca: low PO4: low b/c PO4 b/c need vit D to absorb PTH: high 25(OH)D: low 1,25 (OH)2D: low/normal ```

Question 29

``` Describe the expected lab values for PTH resistance (pseudohypoparathyroidism): Ca: PO4: PTH: 25(OH)D: 1,25 (OH)2D: ```

Answer 29

``` Ca: low PO4: high PTH: high 25(OH)D: normal 1,25 (OH)2D: low ```

Question 30

``` Describe the expected lab values for Vitamin D resistance: Ca: PO4: PTH: 25(OH)D: 1,25 (OH)2D: ```

Answer 30

``` Ca: low PO4: low PTH: high 25(OH)D: normal/low 1,25 (OH)2D: high b/c try to make more vit D to overcome resistance due to defective receptor ```

Question 31

T/F: Treatment for Vitamin D deficiency includes calcitriol, the activated form.

Answer 31

False. Treat with Vitamin D2 or D3. | o No need for activated form (calcitriol) since patient can make PTH

Question 32

``` Which disorder? Ca: low PO4: low PTH: high 25(OH)D: normal/low 1,25 (OH)2D: high ```

Answer 32

Vitamin D resistance

Question 33

``` Which disorder? Ca: low PO4: high PTH: high 25(OH)D: normal 1,25 (OH)2D: low ```

Answer 33

PTH resistance (pseudohypoparathyroidism)

Question 34

``` Ca: low PO4: low PTH: high 25(OH)D: low 1,25 (OH)2D: low/normal ```

Answer 34

Vitamin D deficiency