what are the 5 most common pituitary disorders seen in SA?
- Hypersomatotropism
- Hyposomatotropism
- Cushing’s
- Diabetes insipidus
- Altered libido/ dysmenhorrhea
If an animal is drinking too much there are 2 options- which are they?
- 1ry PU
- 1ry PD
If the animal wants to drink - is it primary PU or primary PD?
primary PD
If an animal has to drink, is it primary PU or primary PD?
primary PU
In Primary PU- which system is involved?
Renal dysfunction- the kidneys can neither concentrate nor dilute their urine properly
In primary PD, which system is involved?
CNS
‘psychogenic’
In primary PD, what can be seen with the USG?
It can vary greatly!! 1.001 –>1.050
In primary PU, increased water intake is normal or abnormal?
abnormal
In primary PU, water consumption is necessary or unnecessary?
necessary- activated by osmo and baroreceptors
How can you tell if an animal has primary PU or primary PD?
You put it into hospital hospital and see if it still drinks.
If animal with PU/PD is in hospital and does not drink, does it have primary PU or primary PD?
Primary PD- doesn’t NEED to drink
What will the USG be for an animals with primary PU?
Poorly modifiable and potentially inadequate
Cushings disease- can the animal have PU/PD?
Yes
Primary PD
Hyperthyroidism in cat- can the animal have PU/PD?
Yes
Primary PD
What disease could this be? What hormone is responsible?
acromegaly- hypersomatotropism
increase in GH —> increase in IGF-1
These cats look normal, but all of them have uncontrollable diabetes and …?
hypersomatotropism
Which hormone do we measure when we are testing for acromegaly?
IGF-1
(it is a better biomarker than pulsatile GH)
What causes hypersomatotropism in the dog?
- exogenous progestins
- ovarian tumour secreting progesterone
How common is hypersomatotropism in cat?
1/ 4 diabetic cats in the UK
What are the clinical features of dogs with hypersomatotropism?
- Increased interdental spaces
- deep set facial features
- insulin resistance
- (hyperglycemia)
What are the clinical features of a cat with acromegaly/ hypersomatotropism?
- Can look normal
- uncontrollable DM
- increased body size
- prognathism (advanced lower jaw)
- organomegaly (kidney/ liver)
How do we diagnose hypersomatotropism in cats?
- Serum IGF
(make sure to do only after one month of insulin treatment for DM- as IGF needs insulin in order to be produced!) - MRI of the head showing pituitary tumour
In diabetes insipidus, will the urine be dilute or hyperconcentrated?
Profoundly dilute.
No ADH to push AQII to the lumenal membrane which means no water can escape the collecting tubules!!
Why does hypersomatotropism lead to PU/PD?
IGF1–> insulin resistance –> hyperglycemia–> glucosuria —> PU/PD
