30 Medical neuro dz Flashcards
ddx scheme for spinal cord disorders
DAMNIT Vdegenerativeanomalous metabolicneoplastic , nutritionalinfectious, inflammatorytraumatic, toxinsvascular disorders**most common
neurodegenerative disorders clinical presentation
slow, insidious onset, progressive(exception IVDD can present peracute thru chronic)familial, hereditarySYMMETRIC (ex. DM)
neuro anomaly disorders clinical presentation
nonprogressive or slowly progressive; symmetricseen early in life (exception vertebral malformations may take time and instability to worsen condition)may be incidental finding (ie. hemivertebra)
metabolic disorders clinical presentation
any age, acute or chronic presentationdiffuse, symmetric nonspecific signs (wax and wane)ex. lysosomal storage disorders
neoplasia and clinical presentation
any age, chronic, progressive with acute deterioration possibleasymmetric (focal–more common) or symmetric
nutritional neuro dz and clinical presentation
raresymmetrical , slowly progressivediffuse or multifocalex. thiamine deficiency, secondary HyperPTH
infxn/inflm neuro dz clinical presentation
acute or chronicasymmetric (more common) or symmetric progressive (but may wax/wane)
traumatic neuro dz and clinical presentation
acute non progressive (may stay static or improve with time)symmetric or asymmetric depending on lesion
vascular neurologic disorders and clinical presentation
acute non progressive (or improvement with time)focal and asymmetric
CSF fluid collection
sensitive but not specific for disease; collecting fluid from subarachnoid spacecerebellomedullary cistern (atlanto-occipital space) vs lumbar cistern (L5-6 dog, L6-7 cats)–collect close to lesioncollect NO MORE THAN 1 ml CSF per 5 kgcytology, culture, virology, immunologic studies
level of spinal cord taper
L5-6 dogL6-7 cat (may be able to do LS in cats)conus medullaris (taper portion) surrounded by nerve roots (caudal equina)subarachnoid space rarely extends to LS in dogs
what is xanthochromic CSF
CSF with yellow or straw-tinged colorsuggests previous subarachnoid hemorrhage (in the absence of hyperbilirubinemia)
normal vs abN CSF cell counts and TP
normal 0-5 WBC x 10^6; 5 WBC x 10^6
Antibody titer testing in CNS for what diseases
Toxoplasma gondiiNeospora canisEhrlichia sppRickettsia sppCoccidiodes immitisreflect direct exposure but does not confirm active infection (may need serial titers)IgM—acuteIgG–chronic
Antigen testing in CNS for what disease
Cryptococcus
high IgA in CSF and serum may indicate what disease process
steroid responsive meningitismost likely secondary to dysregulation of the immune system (TH2 and B cells)**other biomarkers: C reactive protein!
stain used to detect myelin
Luxol fast bluepost mortem staining of spinal cord for diagnosis of degenerative myelopathy
degenerative myelopathy pathophysiology
primary affects spinal cordcharacterized by diffuse axonopathy w necrosis lateral and ventral funiculi of TL spine (T3-L3 progressive UMN paresis and proprioceptive ataxia)demyelination and astrogliosisslowly progressive–no txGSD, Pembroke Welsh Corgi, Boxer, Ridgeback, Huskie
T/FDegenerative myelopathy is a UMN disease
TRUEDM is an UMN disease (T3-L3)10-20% may present with absent patellar reflexeslater in disease fecal and urinary incontinence
genetic risk factor for pembroke welsh corgis and degenerative myelopathy
homozygous missense mutation in superoxide dismutase (SOD1) geneSOD 1 is a gene that converts free radicals to H202 and oxygen to prevent damageabsence of it’s function leads to damage of axons and myelin
most frequently recognized infectious and noninfectious cause of menigomyelitis
infectious–canine distemper virus, protozoanoninfectious–steroid responsive meningitis
T/Fidiopathic/autoimmune meningomyelitides predominate in dog; infectious meningoencephalomyelitis predominate in cats
TRUEidiopathic/autoimmune meningomyelitides — doginfectious meningoencephalomyelitis — cats
idiopathic steroid responsive meningitis-arteritis pathophysiology
systemic immune dz characterized by inflammatory lesions of leptomeninges and associated arteries (occasionally associated with IM polyarthritis)typically respond to GCC (tx over 6 month)acute or chronic presentation; may relapseIMPORTANT DDX FOR CERVICAL SPINAL CORD DZ
CSF fluid in dogs with steroid responsive meningitis
acute: nontoxic PMNchronic: mononuclear cells
monitor treatment success of steroid responsive meningitis with what biomarker?
C reactive protein!IgA may never decrease despite remission
3 forms described for granulomatous meningoencephalomyelitis
- disseminated (most common): acute, rapidly progressive (poor px 8 d)2. multifocal3. focal: slowly progressive, like space occupying mass; may survive longer (114 d)
inflammatory characteristics of GME/MUE
angiocentricnonsupperativemixed lymphoidWHITE MATTER
most common MRI findings of disseminated GME
multiple hyper intensities on T2W or FLAIRscattered throughout CNS WHITE MATTER
characteristics of canine distemper virus menigoencephalomyelitis
unvx dogs; Paramyxoviridae virus family; affects all epithelial tissues (GI, resp, ocular, skin)FLEXOR spasms of limbs,neck, masticatory musclesusually puppies 2-6 mo of ageGRAY matter disease–die within 1 week; nonsupperative inflammationWHITE matter disease–most common demyelination; noninflammatory; die within 4-5 weeksmay progress to necrotizing inflammation
FIP meningitis
mutated form of nonpathogenic feline enteric coronavirusCNS meningitis is with NONeffusive or dry form (less common 30%)–perivascular, pyogranulomatous CNS infiltration
2 clinical syndromes of Toxoplasma and Neospora meningoencephalomyelitis
- meningoencephalomyelitis: cerebellitis, multifocal signs2. myositis-polyradiculoneuritis: LMN deficits; severe muscle atrophy with secondary limb contracture and arthrogryposis in young growing animals
potential sources of bacterial meningomyelitis and spinal cord empyema
–blood from other infectious foci (urine)–direct inoculation (wounds, needles)–direct extension from other parts of body (ocular, ears, cribiform plate)*systemic signs, focal pain, acute, progressive
treatment of bacterial meningomyelitis and spinal cord empyema
ideally culture/sensitivity; tx 1-4 months after clinical signs resolvemetronidazolefluoroquinolonechloramphenicol TMS3rd generation cephalosporins(CCFMS)
Discospondylitis background
bacterial and/or fungalyoung males predominatevariable presentation (pain–>paralysis)spread via hematogenous, lymphatic, directly (rare)may be due to rich vascular supply in end plates and “dead end” capillary loops
most common concurrent condition in dogs with Discospondylitis
UTI
organisms most commonly isolated from Discospondylitis patients
Staph EcoliBrucellaStrepKlebsiella Candida, Aspergillus
Combined blood and urine cultures ID organism in how many Discospondylitis cases
> 40%Burkert et al JAVMA 2005
initial Ab therapy while pending cultures for discospondylitis
selected based on Staph spp BUT 17% staph may be resistant to first generation cephalosporins(consider clavamox, TMS)
T/FFCE may show signs of clinical progression for the first few up to 24 hours after onset
TRUEmay progress initially but then usually static and improve with time
locations of FCE
43-47% LS30-33% cervicothoracicother study says 37-42% T3-L3
theories of how FCE occurs
- nucleus pulpous directly penetrates vessel2. remnant vessel within nucleus pulpous exists3. herniation of nucleus pulpous into bone marrow of vertebral body goes into sinuses4. neovascularization of a degenerated disc
T/FGray matter is more affected than white matter with an FCE
TRUEGray»_space; whitelikely due to higher metabolic demand in gray matter
gold standard dx of FCE
MRIshows focal sharply delineated hyper intensity on T2W Fast spin echo or hypo intense on T1Wischemic lesion to length ratio: compared to length of C6 or T2 body21% MRI of FCE had no detectable lesions
prognosis of FCE after 2 weeks
if no improvement seen in 2 weeks, considered to have a worse prognosis
FCE recovery time until motor, ambulation, and max recovery
motor 6 daysambulation 11 daysmax recovery 3.75 monthsdeRisio et al JVIM 2007 (per TJ page 409)
ischemic lesion length to C6 or T2 length ratiofor predicting outcome in dogs with FCE (Per TJ page 409)
with lesion: length rations >2 60% had unsuccessful outcome< 2 100% had a successful outcome
