Equine Flash Notes - Equine Protozoal Myeloencephalitis Flashcards
what is the classic case presentation of a horse with equine protozoal myelitis?
horse with unilateral gluteal muscle atrophy that is NOT LAME
what two age groups predominate in horses affected with EPM?
1-5 years & over 13 years old
what clinical signs are seen in horses with EPM initially? what about weeks later?
unilateral gluteal muscle atrophy, weks later - broad spectrum CNS signs including multifocal asymmetric cranial nerve involvement, mild lameness/ataxia/head tilt, progressive hemiparesis, horner’s, unilateral masseter/temporalis muscle atrophy, somnolence, seizures, & recumbency - acute or chronic, progressive disease but may wax & wane but can also be subclinical
what differentials should make the list for EPM?
any equine neurologic disease that affects the CNS!!
T/F: there is no definitive antemortem test for EPM
TRUE
what does a positive serology from a western blot for EPM indicate? what about a negative result?
positive - only indicates exposure, negative - should rule out EPM
what is the prognosis for improvement from EPM? what about the prognosis for a cure?
fair to good 60% for improvement & guarded to poor for cure 10-20%
how is EPM prevented?
vaccination & opossum control
how is EPM treated?
antibiotics, anti-inflammatories for severe cases, folate inhibitors, & newer protozoals (triazineones, nitrothiazoles)
what two hosts are required for EPM? how are horses affected?
definitive host - opossum, intermediate host - armadillo, skunk, raccoon, otter, & cat
what agent causes EPM?
sarcocystis neurona
a horse with multifocal asymmetric cranial nerve signs tests negative by western blot for sarcocystis neurona. what is the likelihood of the horse actually having the disease?
very unlikely unless it is a very acute presentation
