Weight gain and hypothyroidism Flashcards
List 3 non-pathological reasons for weight gain
over feeding
reduced exercise
predispositions = age, neutering, breed, owner
List 2 diseases that cause higher caloric demand
acromegaly
insulinoma
List a systemic disease with normal caloric demand which cause weight gain
hyperadrenocorticism
What disease causes normal appetite but decreased metabolic rate
hypothyroidism
what is acromegaly associated with in cats
usually associated with functional pituitary adenoma
mostly males middle age/older
what is acromegaly associated with in dogs
usually unneutered females
due to elevated progesterone levels in the luteal phase OR exogenous progesterone admin (iatrogenic)
what is the clinical signs of acromegaly
weight gain
cutaneous thickening
macroglossia- enlarged tongue
increased dental spacing
signs associated with diabetes- PU/PD, polyphagia
why do animals with acromegaly get diabetes mellitus
due to insulin resistance-
Describe how to diagnose acromegaly
clinical signs
elevated serum GH and IGF-1 (growth hormone)- can get false neg if early insulin therapy
Describe how to treat acromegaly
GOLD STANDARD
Surgery - dogs spay and take mammary strip
Cat- hypophysectomy but expensive
Radiotherapy
drugs such e.g. somatostatin analogues, dopaminergic agonist
what are insulinomas
Functional neuroendocrine tumour of pancreas - B cells
produce excessive insulin
List the clinical signs of insulinoma
increased appetite and weight gain
Weakness, ataxia, collapse, seizures- particularly after exercising/ fasting OR feeding
describe how to diagnose insulinomas
Demonstrate hypoglycaemia (BG <3mmol/l) while clinical signs, which resolve with glucose admin
exclude other causes of hypoglycaemia
what % of insulinomas are visible on ultrasound
50-75%
what is the treatment of choice for insulinoma
excisional biopsy- care is metastatic, but this will help with clinical signs
describe dietary management of insulinomas
multiple small meals high in protein, fat and complex carbs
describe medical management of insulinomas
Diet management
preds- insulin antagonist
More expensive options:
octreotide- inhibits insulin synthesis and secretion
Diazoxide - stimulates gluconeogenesis
Describe the staging of insulinomas
Stage I: Only pancreas affected
Stage II: Regional lymph node metastasis
Stage III: Distant metastasis
What is the prognosis of insulinomas
Stage I- with surgical excision >2 years
Stage II or III- approx. 6 months regardless of treatment.
List 2 causes of primary hypothyroidism
Idiopathic thyroid gland atrophy OR
Immune-mediated lymphocytic thyroiditis
what is the most common cause of hypothyroidism in dogs
> 95% primary causes
describe signalment of hypothyroidism in dogs
Middle age- older
Mostly large breed
describe the signalment of hypothyroidism in cats
Usually older cats following treatment for HyperT4
Often little/ no signs but can worsen renal dx - often silent
Describe the clinical signs of hypothyroidism
very variable - easy to attribute to normal aging
increased weight gain without increased appetite
dull
heat seeking behaviour
increased shedding- dry skin
tragic facial expression
