Come to CE with Me- PPID Update for Vets
Dechra’s continuing education event was largely a basic recap of what’s known on PPID plus info on the new Zygolide FDA-approved generic, but here are some slides that I think were good reminders:
PPID vs EMS (insulin dysregulation)
Signalment- PPID: older like 15+ years, EMS: middle aged 5-15 yrs ± predisposed breed
Clinical Signs- hypertrichosis, muscle atrophy, pendulous abdomen, laminitis, hyperhydrosis, polyuria/polydipsia, EMS: obesity, regional adiposity, laminitis; normal haircoat
Diagnostics- PPID: baseline ACTH, TRH Stim test, EMS: resting glucose, insulin, OST or ITT, metabolic panel
Treatment- PPID: Pergolide, EMS: levothyroxine, metformin, SGLT2 inhibitors
Management- PPID; re-test 1-2 times per year, ± diet, EMS: diet, exercise, supportive care if laminitic
Reminder than PPID and EMS are not mutually exclusive, and there’s an increased chance if one then both
Practical tips:
whole blood samples can wait up to 8 hours in the fridge if necessary before being centrifuged. After centrifugation, plasma samples can be stored in the freezer at -20 degrees C for up to 30 days or -80 C for up to 60 days. Freeze-thaw cycles should be avoided
A basic dental/float doesn’t affect ACTH measures, but avoid diagnostic testing within 24-48 hours of sedation. Low to moderate pain of at least 24 hours duration does not appear to impact diagnostic testing for baseline ACTH or TRH Stim. Testing may be performed on laminitic horses but it is ideal to postpone until severe pain is controlled.
Both glass and plastic EDTA tubes can be used for collection
PPID treatements outside of Prascend/Zygolide:
Cyproheptadine: serotonin antagonist
May be helpful if added to pergolide, but minimal effect alone
Bromocriptine: short acting dopaminergic agonist
limited data
Trilostane: 3-beta-hydroxysteroid dehydrongenase inhibitor
unlikely to benefit PPID- absence of hyperadrenocorticism
PPID Treatment: Evaluate clinical signs ± endocrine testing 1-3 months after starting treatment, and then every 6-12 months
Improved clinical signs and adequate lab response > no change in pergolide dose, reassess every 6-12 months
Poor clinical response with adequate lab response > evaluate for alternate causes and consult with equine endocrinologist or internal medicine specialist
Good clinical response with persistently abnormal endocrine testing> may increase or maintain pergolide dose, consult with specialist
No improvement in clinical signs > increase dose by 1-2 mcg/kg, reassess signs and endocrine testing in 1-3 mo > persistent.recurring clinical abnormalities> refractory case, consult with endocrinologist or internal med spec