Diabetes Insipidus and GH endocrinopathies

Question 1

What is acromegaly?

Answer 1

XS GH causing the overgrowth of bone and soft tissue

Question 2

GH pathway

Answer 2

Anterior pituitary –> GH –> liver –> IGF-1 –> tissues

Question 3

Acromegaly main causes?

Answer 3

progestins in dogs

pituitary tumor in cats

Question 4

_____ can cause GH secretion by decreasing pituitary _____.

Answer 4

Hypothyroidism; Somatostatin

Question 5

Increased GH does what?

Answer 5

increases insulin resistance (causes DM, cats)

increases bone/cartilage/soft tissue proliferation

Question 6

canine Acromegaly clinical signs?

Answer 6

stridor airway compromise - pharyngeal hyperplasia
extra skin 
mammary tumors 
diabetes
space between teeth
gingival overgrowth

Question 7

acromegaly clin path?

Answer 7

hyperglycemia and glycosuria in concurrently diabetic cats
elevated ALP and ALT
mild hyperP
high or low PCV

Question 8

acromegaly dx?

Answer 8

IGF-1 assay

Question 9

most common clinical finding in feline acromegaly?

Answer 9

insulin-resistant DM, but rarely KA because insulin –> liver –> decrease ketogenesis

Question 10

feline acromegaly signs ?

Answer 10

PD/PU/polyphagia
organ enlargements 
cardiomyopathy
lameness
CNS dysfunction in late stages
diabetes

Question 11

acromegaly treatment?

Answer 11

iatrogenic –> discontinue progesterone treatment
natural onset in dog –> spay (OHE)
pituitary tumor –> surgery or radiation
NO medical therapy
give insulin if diabetic

Question 12

acromegaly prognosis?

Answer 12

dog- good

cat- poor (long term)

Question 13

Diabetes insipidus (DI)

Answer 13

PD > 100ml/kg/day

PU > 90 ml/kg/day

Question 14

ADH function?

Answer 14

ADH made in hypo –> PP –> kidney –> water retention

Question 15

DI types ?

Answer 15

Pituitary (central) - ADH does not reach kidney

Nephrogenic - kidney not responsive to ADH

Question 16

DI signs?

Answer 16

history of PU/PD
normal PE and chems
hyposthenuria (<1.008)

Question 17

DI dx?

Answer 17

water deprivation test
vasopressin test
combination of the 2
ADH trial

Question 18

If able to concentrate urine after water deprivation test?

Answer 18

Psychogenic (primary) PD

Question 19

If NOT able to concentrate urine after water deprivation test?

Answer 19

DI. Is it central or nephrogenic? –> ADH (V2) test

Question 20

If able to concentrate urine after vasopressin test?

Answer 20

pituitary (central) DI

Question 21

If NOT able to concentrate urine after vasopressin test?

Answer 21

nephrogenic DI

Question 22

nephrogenic DI treatment?

Answer 22

chlorothiazide

low Na diet

Question 23

______ is associated with prolonged water deprivation because become _____.

Answer 23

hypertonic encephalopathy; hypernatremic

Question 24

pituitary dwarfism incidence?

Answer 24

german shepherds

simple autosomal recessive

Question 25

pituitary dwarfism signs?

Answer 25

truncal alopecia and hyperpigmentation
subpar gonadal development
clinically hypothyroid

Question 26

pituitary dwarfism lab findings?

Answer 26

low IGF1 and basal T4 and gonadotropin

Question 27

pituitary dwarfism treatment?

Answer 27

GH but $$$

thyroxine is better! treats clinical signs

Question 28

NEVER water deprive beyond _____.

Answer 28

3-5% weight loss

Question 29

central DI treatment?

Answer 29

DDAVP