Neurology Problem-Based Studies Part II Flashcards
what is the stride length like with general proprioceptive ataxia?
dysmetria
long stride length: no GP information, so onset of protraction of limb delayed
does the continuous or intermittent tail pull better assess weakness?
continuous tail pull
what is the walking tail pull response like with general proprioceptive deficits?
ataxic response
in what lesions would you see general proprioceptive deficits in all four limbs?
C1-5
C6-T2
what diseases are associated with focal spinal ataxia?
cervical vertebral malformation
trauma
is there a fever in cervical vertebral stenotic myelopathy?
no
what minimum sagittal diameter is considered normal in thoroughbreds?
> 0.5
what view in contrast myelography is best for assessing static compression?
neutral position
what are the aims with intervertebral fusion?
dynamic: avoid further compression
static: atrophy of hypertrophied areas (remodeling and atrophy of articular processes)
what is equine protozoal myelitis caused by?
intracellular protozoa: Sarcocystis neurona, less commonly Neospora hughesi
is there a fever with equine protozoal myelitis?
not usually
what are the diagnostic testing options for equine protozoal myelitis?
PCR: tissue
western blot
IFAT (indirect fluorescent antibody test)
ELISAs: surface antigens
how is equine herpesvirus-1 myeloencephalopathy transmitted?
respiratory
endogenous reactivation
what are the clinical signs with equine herpesvirus-1 myeloencephalopathy?
ataxia
+/- fever, respiratory signs, abortion
bladder dysfunction
cranial nerve deficits, central depression, behavior changes possible
perineal sensory deficits
how can you diagnose equine herpesvirus-1 myeloencephalopathy?
nasal, blood, CSF PCR
what is the average survival for rabies in horses?
5 days
most dead by 10 days
when is the peak prevalence of west nile virus?
september and october
fall
what percentage of horses with west nile virus show a fever?
25%
how is west nile virus diagnosed?
IgM for acute infection: ELISA
post mortem PCR or IHC on CNS tissue
what is the mortality of west nile virus?
20-40%
what does neural invasion in eastern equine encephalitis occur secondary to?
likely to vascular infection or invasion through olfactory epithelium
how can you manage eastern equine encephalitis?
vaccination with killed equine vaccine
mosquito control
not stable in environment
what are the common clinical signs with Anaplasma phagocytophila?
fever
anorexia
icterus
edema
petechiae
how can you treat Anaplasma phagocytophila?
tetracycline
minocycline
doxycycline
what is lyme disease caused by?
Borrelia burgdorferi
how can you treat Borrelia?
minocycline or doxycycline
ceftiofur
steroids
what happens in equine degenerative myeloencephalopathy?
diffuse non-compressive spinal cord disease
degeneration of neurons in white matter of spinal cord
what vitamin plays a significant roll in equine degenerative myeloencephalopathy?
deficiencies in vitamin E
what is the common stride length with GP deficits?
long
what causes diffuse spinal ataxia?
EDM
what causes multifocal spinal ataxia?
EPM
viral encephalitis
tick-borne
what are the two types of cervical vertebral stenotic myelopathy?
developmental disease in young horses
spinal cord compression due to osteoarthritic enlargement of articular processes in older horses
how is minimum sagittal diameter determined?
smallest diameter of cranial aspect of cervical canal
divided by
widest diameter of cranial aspect of vertebral body of same vertebra
how can you manage cervical vertebral stenotic myelopathy in a youngster?
can try dietary management
moderate to severe calorie restriction
what is the definitive host of Sarcocystis neurona?
opossum
what is the best test for equine protozoal myelitis?
ELISA of IgG response to unique surface antigens
serum:CSF titer ratio
what can you use to treat equine protozoal myelitis?
marguis/ponazuril
protazil/diclazuril
rebalance
what is the pathogenesis of equine herpesvirus-1?
multifocal vasculitis with ischemia
direct viral infection of vascular endothelial cells
has vaccination been shown to prevent the neurologic form of equine herpesvirus-1?
no
what are the classic form of rabies?
dumb: progressive depression
furious: progressive aggression
what can be seen in CSF with rabies?
increased protein and lymphocyes
may be normal
is west nile virus spread horse to horse?
no- viremia is too low
are there pathognomonic signs that distinguish west nile virus from other CNS diseases?
no
if a horse with west nile virus significantly improves within __________, then full recovery is expected within 1-6 months in 90%
3-7
is there a vaccine available for west nile virus?
yes, safe
what is the most important amplifier of virus activity in VEE?
horses
when does encephalitis occur with EEE?
after neuronal or hematogenous spread
what can be seen in CSF with EEE?
neutrophilia in acute stages
what fraction of horses that survive EEE have residual neurologic deficits?
2/3
how stable is EEE in the environment?
not stable
how can you diagnose Anaplasma phagocytophila?
PCR
inclusion bodies: 10-18 days post infection
what can be seen in horses with lyme?
ataxia, paresis, weight loss
neck stiffness, behavior
cranial or peripheral neuropathies
concurrent conjunctivitis and uveitis, fever
what are the clinical signs with equine degenerativee myeloencephalopathy?
age <2years
acute or slowly progressive symmetric proprioceptive ataxia
all limbs
no fever
