Parathyroid Gland Pathology

Question 1

What do the chief cells of the PT gland produce?

Answer 1

PTH

Question 2

Is there fat in the thyroid?

Answer 2

No

Question 3

Is there fat in the parathyroid?

Answer 3

Yes - increases with age

Question 4

What is the function of PTH?

Answer 4

Increases the levels of free Ca2+ in the blood

Question 5

What are the effects of PTH?

Answer 5

• Activates osteoclasts
• Increased renal Ca2+ reabsorption
• Increased conversion to active Vitamin D
• Decreases Pi

Question 6

What is the most common cause of hypercalcemia that is clinically apparent?

Answer 6

Malignancy

Question 7

What is the most common cause of incidental hypercalcemia?

Answer 7

Hyperparathyroidism

Question 8

What gender is mainly affected by Primary Hyperparathyroidism?

Answer 8

Females

Question 9

Parathyroid Adenoma

Answer 9

• Almost always solitary
• Increased radionuclide uptake
• Encapsulated lesion

Question 10

Parathyroid Hyperplasia

Answer 10

Usually multiple glands and can be diffuse or nodular

Question 11

Parathyroid Carcinoma

Answer 11

Infiltrate adjacent structures

Question 12

What are the clinical manifestations of primary hyperparathyroidism?

Answer 12

“Painful bones, renal stones, abdominal groans and psychic moans”

Question 13

What is the most common cause of secondary hyperparathyroidism?

Answer 13

Renal Failure

Question 14

Tertiary Hyperparathyrooidism

Answer 14

Autonomous hyperparathyroidism with symptomatic hypercalcemia

Question 15

Hypoparathyroidism

Answer 15

Decreased PTH and hypocalcemia

Question 16

What are the features of hypoparathyroidism?

Answer 16

• Tetany
• Numbness
• Parathesia
• Seizures
• Laryngospasm

Question 17

Chvostek Sign

Answer 17

Contraction of facial muscles from tapping facial nerve

Question 18

Trousseau Sign

Answer 18

Carpal spasms from occlusion of blood in the forearm by a BP cuff

Question 19

Pseudohypoparathyroidism

Answer 19

Normal PTH with hypocalcemia due to end organ resistance.

Question 20

A 38-year-old man sees his physician because of abdominal pain, nausea, and constipation for the past 3 days. On physical examination he has no palpable abdominal masses and bowel sounds are present. His lungs are clear to auscultation. He has a heart rate of 80 with an irregular rhythm. An EKG demonstrates a shortened QT(corrected) interval and a prolonged PR interval. He has a stool positive for occult blood. Upper GI
endoscopy reveals multiple 1 cm diameter shallow ulcerations of the gastric antrum. Which of the following laboratory test findings is most likely to be present in this man?

A) Thyroid peroxidase antibody of 4 IU/mL
B) Serum calcium of 12.4 mg/dL (ref 8.5 -10.5 mg/dl)
C) Blood glucose of 225 mg/dL (ref 70- 100 mg/dl)
D) Total serum thyroxine of 21 ug/dL (ref 5-11 ug/dl)
E) Plasma cortisol of 45 ug/dL at 8 am (ref 4-22 ug/dl)

Answer 20

B) Serum calcium of 12.4 mg/dL (ref 8.5 -10.5 mg/dl)

Question 21

A 50 year old man diagnosed with papillary thyroid carcinoma underwent total thyroidectomy. Within a few hours of surgery the patient complained of tingling of his fingers.
Which of the following laboratory tests should be ordered to direct further therapy for this patient.

A. serum TSH
B. serum parathormone
C. serum ionized calcium
D. serum Total T4

Answer 21

C. serum ionized calcium