Endocrine Pathology

Question 1

What skin lesion is associated with cushings disese

Answer 1

Calcinosis cutis

Question 2

Normally the adrenal glands should have what ratio of cortex to medulla?

Answer 2

3:1

Question 3

What MDx would describe a adrenal gland with a 4:1 ratio of cortex:medulla?

Answer 3

Adrenocortical hyperplasia

Question 4

Dog with tragic face
Mucopurulent exudate from the eyes
Significant subcutaneous fat

What endocrine disorder?

Answer 4

Hypothyroidism

Question 5

What consequence of hypothyroidism can be seen in the heart?

Answer 5

Coronary artery atherosclerosis

-hypercholesterolemia –> fatty tissue and macrophage infiltrate in the vascular wall

Question 6

What hormonal abnormality is associated with thyroid nodular hyperplasia?

Answer 6

Hyperthyroid

Question 7

What changes in the heart can be associated with hyperthyroidism

Answer 7

Hypertrophic cardiomyopathy

• enlarged with pale apex
• sunken necrosis and fibrosis

Question 8

What is the pathogenesis in which cardiac hypertrophy arises from hyperthyroidims?

Answer 8

Hyperthyroidism increased BP
Overcome increased afterload

Necrosis due to lack of blood supply to the cardiomyocytes

Question 9

What is the pathogenesis of acute kidney infarct in a hyperthyroid cat?

Answer 9

High BP -> cardiac hypertrophy –> diseased heart with poor flow –> thrombosis and embolism

Question 10

You have bilateral parathyroid hyperplasia, is this primary or secondary?

Answer 10

Secondary –> both enlarged because of an outside cause

Question 11

What is the stimulus for bilateral parathyroid hyperplasia?

Answer 11

Hypocalcemia -> stimulate parathyroid to increase PTH

Question 12

What are the two inflammatory disorders of the endocrine system?

Answer 12

Lymphocytic thyroiditis

Lymphocytic adrenalitis

Question 13

Mass in the medulla of the adrenal gland of the horse

Answer 13

Pheochromocytoma

Question 14

What common mass is found in the pancreas of a ferret?

Answer 14

Pancreatic islet carcinoma

AKA insulinoma

Question 15

What two endocrine tumors are common in ferrets?

Answer 15

Adrenocortical tumor -> hyperestrogenism

Pancreatic islet cell tumor -> hypoglycemia

Question 16

What is the MDx of a goat with enlarged thyroid in a goat

DDx?

Answer 16

Thyroid hyperplasia

Goiter

Question 17

T/F: goats affected with goiter are hyperthyroid

Answer 17

False!

Hypothyroid
Can’t make t4 -> Pituitary makes TSH –> ++ thyroid

Question 18

What are the possible EDx of goiter ?

Answer 18

Iodine deficient diet

Goiterogenic substances
-brassica plants or sulfonamides (interfere with the production of T4

Congenital (enzyme defect)

Excess dietary iodide

Question 19

How is alopecia associated with hypothyroid?

Answer 19

Cutaneous mucinosis (Chinese sharpei)

Question 20

Doggo

Gain in body weight
Bilaterally symmetrical alopecia, scaly skin
Myxedema

Answer 20

Hypothyroidism

Question 21

What are the typical lesions causing canine hypothyroidism?

Answer 21

Lymphocytic thyroiditis
Thyroid atrophy

-> no functional response to TSH due to inflammatory infiltrate or atrophy = no goiter

Question 22

Cat

Polyphagia with weight loss
Inappropriate urination
Mass in the thyroid.

What does the cat have too much of?

Answer 22

T3/T4

Question 23

What is the MDx for a nodular mass in the thyroid?

Answer 23

Nodular (adenomatous) thyroid hyperplasia

Question 24

What is the EDx of feline hyperthyroidism?

Answer 24

Adenomatous hyperplasia
Adenoma
Carcinoma

Question 25

T/F: you should expect to see an increase in T4 in a thyroid follicular cell tumor in a dog

Answer 25

False

Depends on differentiation of the cells
Almost always malignant and not producing thyroid hormone

Question 26

T/F: in thyroid neoplasia, cats usually have productive and benign neoplasia while dogs usually have non-productive and malignant neoplasia

Answer 26

True

Question 27

Doggo PM

Hypercalcemia
Rubber jaw (fibrous osteodystrophy)
Small pale kidney
Enlarged mass by thyroid

Dx?

Answer 27

Parathyroid hyperplasia

-> hyperparathyroid

Question 28

What is the cause of parathyroid hyperplasia?

Answer 28

Hypocalcemia

Question 29

What two main conditions can cause hypocalcemia leading to parathyroid hyperplasia?

Answer 29

Nutritional

• high P/low Ca
• hypovitamin D

Renal

• high P
• reduced vitD

Question 30

What is a primary cause of hyperPTH?

Answer 30

Parathyroid adenoma

Question 31

What neoplasias are associated with pseudohyperparatyroidism?

Answer 31

Anal sac or lymphoma

–> PTH-RP-> hypercalcemia

Question 32

What is the pathogenesis of fibrous osteodystrophy in hyperPTH patients?

Answer 32

PTH stimulated increased reabsorption of bone

Chronic PTH-> stimulate marrow stromal cells to differentiate into fibroblasts

High P and low vitD -> low Ca-> inability to properly mineralized growth bone due to low Ca and uremic acidosis