PPID

Question 1

What is PPID

Answer 1

Pituritary pars intermedia dysfunction - pituitary disease - hyperadrenocrotism - ‘equine cushings’

Question 2

PPID signalment

Answer 2

Older horses - older they are more likely

>10 poss, >20 likely

Question 3

PPID CSs (6)

Answer 3

1. hypertrichosis - often begins as slow shedding then get retention of hair coat - thick regrowth within 1/2mo of clipping year round
2. laminitis - due to insulin dysregulation. Divergent rings suggestive of previous subclinical laminitis.
3. PU/PD - may not be boticed
4. lethargy
5. excessive sweating
6. weight loss/muscle mass atrophy

Question 4

Laminitis with PPID

Answer 4

Likely due to insulin dysregulation. Divergent rings suggestive of previous subclinical laminitis.
Peak incidence September, non PPID - May

Question 5

Uncommon neurological PPID presentation

Answer 5

blindness, collapse or seizures.

Due to expanding pituitary increasing pressure on the brain

Question 6

Altered parameters on bloods seen with PPID

Answer 6

Hyperglycaemia, raised liver enzymes, increased triglycerides, relative neutrophila & lympopenia

Question 7

1st line test for PPID

Answer 7

Resting plasma [ACTH] - can be taken any time of day
More sensitive July-November
PPID = increased [ACTH]
Recommended ACTH levels checked 2x annually

Question 8

2nd line test for PPID

Answer 8

TRH stim - good for early/subtle cases
ONLY use mid November - mid July
Withhold concentrate feed for 12h prior
Baseline ACTH, inject TRH IV, measure ACTH 10mins later
High ACTH at 0 or 10 = PPID
Not within 24hrs of an oral sugar test

Question 9

PPID management

Answer 9

• regular clipping
• dental care - prevent infections, maximise nutrient intake
• avoid concentrates high in soluble carbohydrates - try oil or low glycemic index options if need to gain weight
• regular farriery
• vaccines, worming, ectoparasite tx

Question 10

Main medical Tx PPID

Answer 10

Dopamine antagonism - pergolide mesylate (prascend) PO SID
Repeat ACTH stim 1mo later
CSs improvement expected 6-12wks
titrate to lowest possible dose

Used off licence in pregnant mares - care agalactica. Wean off 4-6wks prior to partition.

Question 11

Additional medical tx PPID

Answer 11

Trilostane - targets enzyme responsible for cortisol production from cholesterol.
little evidence of benefit in horses

Question 12

If insulin resistance suspected to be an issue in PPID can use

Answer 12

Metformin - insulin sensitising drug.