The Ageing Horse Flashcards
What is a geriatric horse?
- > 15 years (which accounts for 30% of equine population)
What can slowing down be a sign of?
- PPID
- Pain
- Dental dx
- GI dx
- Ophtalmic dx
- neoplasia
‘Muscle Wastage’ - what can cause this?
- PPID
- Orthopaedic disease
what can cause hirsuitism?
PPID
What can cause ‘Weight loss’
- Muscle wastage
- Dental dx
- PPID
- GI dx
- NEoplasia
What metabolic diseases do we need to be thinking about
- PPID ‘cushings’
- Insulin dysreg/ EMS
T/F PPID should be considered as contributing factor in horses >15 yo
true
Describe what IS PPID?
What is the pathology in PPID?
- Exactly how this causes many of the clinical signs is not known,
many hormones are derived from the pars intermedia and will
play a role - Excess cortisol is believed to be the main problem
*Insulin dysregulation found in approx. 1/3 of PPID cases
CLS of PPID
- Hypertrichosis (pathognomonic)
- Laminitis (‘HAL’) – most significant clinical sign
- Redistribution of body fat/weight loss/muscle loss
- Pot belly appearance
- Exercise intolerance/low grade malaise/lethargy
- Recurrent/chronic infections – solar abscess, tooth root abscess,
sinusitis, dermatitis, endo- /ecto-parasites etc - PU/PD
- Abnormal sweating
When would we do Basal ACTH for PPID Daignostics.
- Best for many, severe or advanced clinical signs; older animals
- High clinical suspicion
- More sensitive in the Autumn
How to take a Basal ACTH sample?
- Collect an EDTA blood sample (any time of day) – normally purple top
- Keep sample cool (ice packs or fridge)
- Ideally centrifuge to separate the plasma
- Take the plasma off the sample and place in new EDTA tube
- Post in cool bag provided with cool packs
- (Plasma can be frozen (centrifuged only) – but avoid freeze/thaw cycles)
When should we do TRH STim test ?
- Best for few, mild or early clinical signs; younger animals
- Lower clinical suspicion
- Also useful when basal ACTH result is equivocal or PPID is suspected in spite of a
negative basal ACTH test - More sensitive than basal ACTH
When might TRH Stim test give false neg?
- TRH responses in the Autumn may give false positives – only useful in these months
to identify negative cases.
HOW to do a TRH Stim sample?
- Collect blood in EDTA tube for baseline ACTH
- Inject 1mg TRH IV
- Collect second EDTA blood sample exactly 10 mins later
- Handle this sample in the same way as for basal ACTH
DOpamine AgonistId Tx?
Domaine Agonist
Cyproheptadine hydrochloride
Describe how Dopamine agonist is used
- Reimposition of dopaminergic inhibition of pars intermedia
- Effective dose variable
- Monitor ACTH and clinical signs and adjust (1-3month later)
- If not responding can increase further
Dopamine agonist - name of drug?
Pergolide mesylate - only licensed option. -2mcg/kg per os q24hrs
Describe cyproheptadine hydrochloride
- Decreased ACTH secretion for pars distalis in humans in response to
cyproheptadine - Used in refractory cases although no benefit over pergolide seen in
studies
What other management for PPID tx?
- clipping
- diet
- Routine care
What Oa signs might be described with old age?
- ‘Difficulty getting up’
- ‘Clicking back legs’
- ‘Lame on both legs’
- ‘Picks up on Bute’
- ‘Lost weight’ – muscle or fat loss?
- Narcolepsy
Osft tissue degeneration?
- tendon and lig laxity from PPID
How can we use OA in geriatric horse
*NSAIDs
*IA steroids
* Adjunctive therapies
* Environmental management
* Keep up gentle movement
* Keep warm
* Supplements ?!?
What common dental dx with old age?
- Tooth loss
- Smooth mouth
- Loose teeth
- Malocclusions
- Overgrowth
- Diastemas
- Equine Odontoclastic tooth resorption and Hypercementosis (EOTRH)
