Principles of Testing for Endocrine Disease

Question 1

What are the disorders of the Pituitary Gland that have been diagnosed in small animals?

Answer 1

• Pituitary dwarfism
• Acromegaly
• Diabetes insipidus
• SIADH (Syndrome of inappropriate antidiuretic hormone secretion)

Question 2

What are the disorders of the Thyroid Gland that have been diagnosed in small animals?

Answer 2

• Hyperthyroidism

- Hypothyroidism

Question 3

What are the disorders of the Parathyroid Gland that have been diagnosed in small animals?

Answer 3

• Hypoparathyroidism

- Hyperparathyroidism

Question 4

What are the disorders of the Pancreas that have been diagnosed in small animals?

Answer 4

• Diabetes mellitus

- Insulinoma

Question 5

What are the disorders of the Adrenal Gland that have been diagnosed in small animals?

Answer 5

• Hyperadrenocorticism
• Hypoadrenocorticism
• Phaeochromocytoma
• Hyperaldosteronism
• Adrenal hyperplasia syndrome

Question 6

What are the disorders of the Intestines and Renal system that are considered more rare, which have been diagnosed in small animals?

Answer 6

• Gastrinoma

- Polycythaemia

Question 7

What are the top 3 endocrine disorders of the Dog?

Answer 7

1) Diabetes Mellitus
2) Hyperadrenocorticism
3) Hypothyroidism

Common in only certain breeds and should be considered in ddx:
- Hypoadrenocorticism

Question 8

What are the 2 most common endocrine disorders of the Cat?

What are the 2 emerging endocrine disorders of the Cat?

Answer 8

1) Diabetes mellitus
2) Hyperthyroidism

Emerging:

1) Acromegaly
2) Hyperaldosteronism

Question 9

What is the normal reference range for Glucose in the Dog?

Answer 9

3.5 - 7.5 mmol/L

Question 10

When measuring Insulin levels, what other parameter MUST you measure ?

Answer 10

Insulin should always be measured with Glucose

Question 11

When measuring PTH levels, what other parameter MUST you measure ?

Answer 11

Calcium should always be measured with PTH

Question 12

Which test is more confirmatory; Basal Hormonal Level of Dynamic Test?

Answer 12

Dynamic Test

Question 13

Define Sensitivity

Answer 13

Sensitivity is the number of Diseased patients that test correctly POSITIVE

aka Diseased, test Truly Positive

Question 14

Define Specificity

Answer 14

Specificity is the number of Healthy patients that test correctly NEGATIVE

aka Healthy, test Truly Negative

Question 15

A Screening Test should have high or low Sensitivity and Specificity?

Answer 15

High Sensitivity

Lower Specificity

Question 16

A Diagnostic Test should have high or low Sensitivity and Specificity?

Answer 16

High Specificity

Lower Sensitivity

Question 17

How can we assess Adrenal function?

Answer 17

Basal Test: cortisol levels

Dynamic: ACTH response test + Low dose dexamethasone response test

Question 18

How can we assess Thyroid function?

Answer 18

Basal Tests: 
Total T4
Free T4 (more accurate than total T4)
Total T3 (rarely used)
TSH (cant use in cats, helpful in diagnosing hypothyroidism in Dogs)

Question 19

How can we assess Parathyroid function?

Answer 19

Basal Tests:
PTH (must also measure Ca)
PTHrp: used when malignancy is a ddx

Question 20

What hormone can we test for Dwarfism and Acromegaly?

Answer 20

• Growth Hormone: used for Dwafism and Acromegaly

- IGF-1: used for Dwarfism and Acromegaly

Question 21

What hormone can we test for Insulinoma’s and Diabetes Mellitus?

Answer 21

• Insulin

note: must also test glucose levels too

Question 22

What hormone can we test for Alopecia X

Answer 22

• 17-OH Progesterone

Question 23

What hormones can we test for Adrenal tumors?

Answer 23

• 17-OH Progesterone

- Aldosterone (especially when animals are not presenting with abnormal electrolyte changes)

Question 24

What hormone can we test for erythrocytosis?

Answer 24

• Erythropoietin