Robbins - Parathyroid

Question 1

Polygonal cells w/ central, round, uniform nuclei, pink cytoplasm, dark blue secretory granules, sometimes water-clear appearance (glycogen)

Answer 1

Chief cells

Question 2

Large cells, many mitochondria, clear glycogen

Answer 2

Oxyphil cells

Question 3

PTH - functions (4)

Answer 3

Increased calcium reabsorption, increase phosphate excretion, increase vitamin D activation (calcium absorption), release calcium and phosphate from bone

Question 4

Woman, normal checkup, high Ca++, high PTH

Answer 4

Primary hyperparathyroidism

Question 5

Small solitary lesion in the neck, well-circumscribed, hypercellular w/ monomorphic polygonal cells w/ secretory granules, surrounded by normal tissue w/ shrunken glands

Answer 5

Parathyroid adenoma

Question 6

Parathyroid adenoma (solitary mass, nothing else) - genetics

Answer 6

Cyclin D1

Question 7

Parathyroid adenoma can be associated w/ what syndromes? Genetics?

Answer 7

MEN type 1 = MEN1
MEN type 2 = RET
Familial hypocalciuric hypercalcemia = CASR

Question 8

Minor enlargement of all 4 parathyroid glands, hypercellular chief cells with little to no fat

Why not parathyroid carcinoma?

Answer 8

Parathyroid hyperplasia

No invasion or metastases

Question 9

Hyperparathyroidism:

- Bone

Answer 9

• Osteoporosis (decreased bone mass)

Question 10

Hyperparathyroidism, vascular and hemorrhagic mass of fibrous tissue and macrophages w/in bone

Answer 10

Brown tumor

Question 11

Hyperparathyroidism, peritrabecular fibrosis, cystic brown tumors, increased osteoclast activity

Answer 11

Osteitis fibrosa cystica (rare)

Question 12

Hyperparathyroidism:

- Kidneys

Answer 12

Nephrolithiasis (calcium), nephrocalcinosis (calcification of renal interstitium and tubules)

Question 13

Hyperparathyroidism:

- Stomach, lungs, heart, and/or blood vessels

Answer 13

Calcification

Question 14

Symptomatic hypercalcemia - bones, stones, moans, groans

Elevated ___ on lab evalulation

Answer 14

Hypercalcemia of malignancy (most likely)

PTHrP

Question 15

Most common sources of hypercalcemia of malignancy

Answer 15

Lung, breast, H/N, renal cancers

Multiple myeloma

Question 16

Hypercalcemia:

- Bones

Answer 16

Osteoporosis, fractures, brown tumors

Question 17

Hypercalcemia:

- Kidneys

Answer 17

Nephrolithiasis (painful, obstructive urination), chronic renal insufficiency (polyuria and polydipsia)

Question 18

Hypercalcemia:

- GI

Answer 18

Constipation, ulcers, pancreatitis, gallstones

Question 19

Hypercalcemia:

- CNS

Answer 19

Depression, lethargy, seizures

Question 20

Hypercalcemia:

- Neuromuscular

Answer 20

Weakness, fatigue

Question 21

Hypercalcemia:

- Cardiac

Answer 21

Aortic/mitral calcification

Question 22

Secondary hyperparathyroidism - causes

Answer 22

Chronic hypocalcemia - renal failure, dietary deficiency, vitamin D deficiency, malabsorption

Question 23

Tertiary hyperparathyroidism - what is it?

Answer 23

Autonomous, excessive parathyroid glands

Question 24

Most common cause of hypoparathyroidism?

Answer 24

Surgical removal w/ thyroid

Question 25

Chronic mucocutaneous candidiasis, adrenal insufficiency, hypoparathyroidism

Genetics?

Answer 25

Autoimmune polyendocrine syndrome type 1 (ASP1)

CASR gain of function

Question 26

Clinical symptoms of hypoparathyroidism

Exam signs?

Answer 26

Tetany (paresthesias, spasms), mental status changes (minor to severe), parkinsonian movement (paradoxical calcification of basal ganglia), long QT interval

Chvostek and Trousseau signs (hypocalcemia)

Question 27

High PTH, hypocalcemia, hyperphosphatemia

Association?

Answer 27

Pseudohypoparathyroidism (resistance to PTH)

G-protein defect –> TSH, FSH/LH resistances