Endocrine Disorders

Question 1

what is euthyroid sick syndrome from

Answer 1

• changes to serum T3 or rT3 not caused by thyroid effect (illness or drugs)

Question 2

hyperthyroidism; serum levels, causes of primary vs secondary vs other causeand treatment

Answer 2

• High serum T3/T4
• Primary = thyroid adenoma in cats, thyroid carcinoma in dogs
• Secondary = pituitary adenoma
  o Graves disease = antibodies bind to TSH receptor and mimic = production of thyroid hormones
• Treating = reactive iodine, thyroidectomy, nutrition (iodine deficient), methimazole

Question 3

hypothyroidism; serum levels, causes of primary and treatment

Answer 3

• Low serum T3/T4
• Primary = immune mediated in dogs and idiopathic atrophy in cats
• treating = levothyroxine

Question 4

clinical signs of hypothyroidism

Answer 4

-intolerance to cold
-weight gain
-lethargy
-slow pulse
-slow reflexes
-depression

overall decreased metabolic processes

Question 5

clinical signs of hyperthyroidism

Answer 5

-intolerance to heat
-weight loss
-rapid pulse
-increased activity
-rapid reflexes
-excitability

overall increased metabolic processes

Question 6

what species do hyper vs hypothyroidism affect more

Answer 6

hypo = middle aged dogs
hyper= middle aged cats

Question 7

how do diagnose hypoparathyroidism, signs

Answer 7

hypocalcemia, low PTH, hyperphosphatemia

cardiac arrhythmias, seizures, weakness, ataxia

Question 8

hyperparathyroidism; cause of primary vs secondary, diagnosis, clinical signs

Answer 8

• Primary = excessive PTH secretion
• Secondary = kidney failure or vitamin D deficiency
• Diagnosis = hypercalcemia, high PTH, low phosphate
• Increased bone resorption, mineralization of soft tissues, polydipsia/uria (Ca blocks ADH)

Question 9

hypoadrenocorticism; causes of primary vs secondary, diagnosis of primary

Answer 9

• Secondary = undersecretion of cortisol and sex steroids due to loss of ACTH stimulation
• Primary (addisons) = hyposecretion of all corticosteroids
  o Diagnosis = ACTH stimulation test

Question 10

what is the other name for addisons disease

Answer 10

hypoadrenocorticism

Question 11

another name for cushings disease

Answer 11

hyperadrendocorticism

Question 12

hyperadrenocorticism; causes, diagnosis, treatment

Answer 12

-most common cause is administration of exogenous glucocorticoids
-an ACTH oversecreting pituitary tumor (secondary) is about 80% of endogenous cushings syndrome
-adrenal disease is rare

dexamethasone suppression test (exogenous)
ACTH stimulation test (endogenous)

dogs= mitotane and trilostane
horses = pergolide, PPID occurs in 20% of horses over 15

Question 13

diabetes mellitus; causes, treatment

Answer 13

• Type 1 = insufficient insulin, immune mediated or post pancreatitis in dogs, amyloidosis in cats
• Type 2 = insulin resistance, hyperadrenocortism or glucocorticoid and obesity
• Treatment; insulin, diet changes and weight loss

Question 14

diabetes insipidus; central vs nephrogenic, causes

Answer 14

-central = Lack of ADH secretion from the pituitary caused by injury to pars nervosa or supraoptic nucleus, injury or inflammation to pars nervosa or SO nucleus in hypo

-nephrogenic = Reduced ability of the kidneys to respond to ADH, acquired or hereditary