EQ SC Disease 2 Flashcards
EPM testing
Antibodies in serum only indicate exposure - which most horses have been exposed
Antibodies in CSF
- infection of CSF and intrathecal antibody production
Compromised BBB
Contamination of CSF w peripheral blood
Effective testing for EPM
Check ratio of concentration of antibodies to S. Neruona and N. Hughesi in serum, to CSF (serum/titer ratio)
High titer or low serum/titer ratio in conjunction with clinical signs of EPM is strongly suggestive
Diagnosing EPM
Sudden onset of neurological signs consistent w EPM
Possibility of exposure
Presence of antibodies
Treating EPM
Sulfadiazine
Pyrimethamine
Duration of treatment is 6-9 months
Drugs have poor CNS penetration ability
Second generation treatment
Ponazuril (marquis)
Diclazuril (protazil)
Decoquinate (compounded)
Ponazuril
Requires a loading dose and treatment lasts about 27 days
Co-administration w oil raises absorption and CSF concentrations. FDA approved
^^$$ ($800/month)
Diclazuril
Food pellet that mixes with food
No loading dose, treatment for 28 days . FDA approved
$$$ (800/month)
Decoquinate
Oral admin for 10 days
Not FDA approved
Cheapest form of treatment
Why is co treating with anti-inflammatory drugs a good idea>
Anti inflammatory drugs
Vitamin E - 6-8kIU/day
Immunomodulators: leavmisole, Eq stim, equimune, zylexis
EPM prognosis
Progressive disease and athletic performance is poor with no treatment
50-80% of treated horses improve
10-20% of treated horses recover fully
10-20% of treated horses relapse
EPM differentials
Trauma
Equine herpesvirus myeloencephalopathy
Parasitic myeloencephalitis
Polyneuritis equi
EPM prevention
Reducing ingestion by opossum feces
Routine health maintenance of barn cats
Stop feeding barn cats in open area to reduce opossum attraction
Equine herpes virus myeloencephalopathy
Caused by EHV1
- respiratory disease in young horses
- abortion in mares
- pneumonia in neonatal foals
Pathogenesis of EHM
Endotheliotropic, immune mediated vasculitis of arterioles of spinal cord/brain
Causes hemorrhage, thrombosis, ischemia of white matter and occasionally the gray matter of the Spinal cord /brain
Signalment for EHM
Usually adult horses
Pregnant or lactating mares
May effect more than one horses on a premise. Close contact airborne
EHV1 transmission
Herpes becomes latent in host & becomes activated by stress and then becomes infectious
EHM history
Sudden onset of in coordination
Starts with one horse then many affected
Reported on breeding farm, race track or training stable
Associated with respiratory disease or abortion
Often late winter or early spring
Clinical findings for EHM
Biphasic fever - day 1-2, day 6-7 (neuro signs begin)
Nasal discharge
Depression
Hind limb weakness/in coordination
Loss of bladder tone
Dog sitting position
Recumbancy
EHM neurological signs
Symmetric paresis, ataxia, hypometria in pelvic limbs
Symmetric paresis, ataxia, hypometria in pelvic and thoracic limbs
May exhibit weak, floppy tail, inability to defecate & urinary incontinence
CN deficits & seizures (rare)
EHM diagnostic testing
CBC - normal
Biochem - CK if recumbent
CSF - xanthochromia & increased protein
Nasal swab & whole blood: PCR test
Virus isolation & serology not clinically useful
EHM differentials
Trauma
Equine protozoal myeloencephalitis
Polyneuritis equi
Botulism
EHM treatment
Isolation
Primary supportive care
Anti inflammatory meds
Antiviral meds
Anti inflammatory meds
Flunixin
DMSO
Dexamethasone
