Disorders of the Parathyroid

Question 1

Parathyroid Glands are located

Answer 1

on the posterior surface of the thyroid

Question 2

Parathyroid Glands are responsible for secretion of

Answer 2

PTH (parathyroid hormone) - regulating serum calcium levels

Question 3

Increase in PTH causes an increase in

Answer 3

serum calcium

Question 4

Decreased PTH causes a decrease in

Answer 4

serum calcium

Question 5

PTH acts on several targets to alter serum calcium levels by

Answer 5

bones
kidneys
GI tract

Question 6

Vit D metabolism is necessary for

Answer 6

calcium homeostasis and absorption
no vit D = no calcium absorption
Vit D is activated in the kidneys
PTH stimulates activation

Question 7

Calcitonin functions to lower

Answer 7

serum calcium

Question 8

Calcitonin is secreted by the

Answer 8

thyroid in response to elevated serum calcium

Question 9

Hyperparathyroidism is

Answer 9

overactive parathyroid –> excess levels of PTH

Question 10

Two types of Hyperparathyroidism

Answer 10

Primary and secondary
Primary = problem is the parathyroids themselves
Secondary = problem is outside of the parathyroid

Question 11

Most common cause of Primary Hyperparathyroidism

Answer 11

single gland adenoma
associated with MEN 1, 2, 4, other risks = head and neck radiation

Question 12

Primary Hyperparathyroidism sxs

Answer 12

presents related to hypercalcemia:
bones, stones, abdominal groans, psychic moans, fatigue overtones

Question 13

Primary Hyperparathyroidism dx starts with

Answer 13

serum calcium
> 14 or PTH > 5x normal think cancer
urinary calcium to confirm - should be normal or high
low = kidney

Question 14

Imaging not necessary for dx but used for preop (Hyperparathyroidism)

Answer 14

US
SPECT CT

Question 15

Primary Hyperparathyroidism treatment

Answer 15

mainstay is parathyroidectomy
caution = transient hypocalcemia post-op
potentially take too much parathyroid = hypoparathyroidism

Question 16

Primary Hyperparathyroidism alternative treatment

Answer 16

Osteoporosis medications
DEXA every 1-2 years
Maintain hydration to prevent kidney stones
physical activity to maintain bone strength
AVOID thiazides diuretics, lithium
Loop diuretics to decrease calcium levels

Question 17

Secondary Hyperparathyroidism treatment

Answer 17

treat underlying cause if secondary
increase calcium if low (diet, supplements)
decrease phosphorus if high
increase Vit D if low
Hemodialysis if due to CKD

Question 18

Hypocalcemia may cause

Answer 18

secondary hyperparathyroidism
low serum Vit D

Question 19

Hypoparathyroidism is

Answer 19

reduced function of the parathyroid
can be due to surgical removal of the parathyroid(s) and/or thyroid glands
can also be due to autoimmune disorders or genetic mutations

Question 20

Hypothyroidism presentation

Answer 20

may be asymptomatic
sxs related to hypocalcemia:
paresthesias (hands, feet, perioral) - muscle spasms/ cramps - seizures
arrhythmias, wheezing, SOB, stridor

Question 21

Hypothyroidism PE findings/ signs

Answer 21

Chovstek’s sign - tap on facial nerve -> ipsalateral grimace
TRousseau’s sign - involuntary movement of wrist/hand with BP cuff inflation
Hyperreflexia

Question 22

Pts with Hypothyroidism are also more prone to

Answer 22

cataracts

Question 23

Hypothyroidism workup

Answer 23

reduced serum calcium
increased serum phosphorus
reduced PTH
no imaging necessary

Question 24

Hypothyroidism treatment

Answer 24

mainstay treatment is calcium and activated Vit D supplement - lifetime treatment
major side effects - constipation, caution for hypercalcemia, esp in CKD
if low magnesium - supplement
Thiazide diuretics to treat hypercalciuria