Misc neuro disorders Flashcards
(53 cards)
1
Q
rundown of MS?
A
- most common acquired disease of myelin. Mainmjob of myelin is to increase speed at which impulses propagate along myelinated fiber
- body mistakenly directs Abs and WBCs (lymphocytes, macrophages, proteolytic enzymes) against proteins in myelin sheath
- results in inflammation and injury to sheath and ultimately to nerves that it surrounds
- the result may be multpile areas of scarring (sclerosis)
- initiating cause is unkown!
2
Q
Where are the areas of demylenation of MS found?
A
- found scattered in white matter of brain, spinal cord and optic nerve
- eventually damage can slow or block nerve signals that control muscle coordination, strength, sensation and vision
3
Q
Pathogenesis of MS? Characterized by?
A
- involves autoimmune mediated inflammatory demyelination and axonal injury:
- peri-vascular infiltrates by lymphocytes and monocytes
- MHC antigen expression
- HLA-DR2 - increases risk
- characterized by relaspses, followed in most cases by some degrees of recovery: relapsing-remitting
- eventually progresses to continual disease
4
Q
Areas commonly affected by MS?
A
- optic nerve
- corticobulbar tracts (speech and swallowing)
- corticospinal tracts (muscle strength)
- cerebellar tracts (gait and coordination)
- spinocerebellar tracts (balance)
- longitudinal fasciculus (conjugate gaze, EOMs)
- posterior cell columns of spinal cord (position and vibratory sense)
5
Q
MS most common in?
A
- in women
- usually occurs b/t ages 15-50
- annual incidence rate is increasing
- genetic link established
- geographical factors: more common in countries with temperate climates, including Europe, southern canada, N US, and SE australia, reason unknown
6
Q
Enviro factors in MS?
A
- many viruses and bacteria have been suspected of causing MS, most recently the EBV
- some studies have suggested that developing infection at critical period of exposure may lead to conditions conducive to development of MS a decade or more later
7
Q
Sxs of MS?
A
- weakness, numbness, tingling, or unsteadiness in limb - “Lhermitte’s sxs)
- unilateral visual impairment
- fatigue
- spastic paraparesis
- diplopia
- disequilibrium
- muscle weakness
- sphincter disturbance such as urinary urgency or hesitancy
- dysarthria
- mental disturbance
8
Q
Signs of MS?
A
- optic neuritis (can often be initial episode for pt who develops MS)
- opthalmoplegia
- nystagmus
- spasticity or hyperreflexia
- babinski sign
- absent abdominal reflexes
- labile or changed mood
9
Q
Diff in MS in younger and older pts?
A
- younger: subacute or acute onset of focal neuro sxs and signs reflecting:
optic nerve, pyramidal tracts, posterior columns, cerebellum, central vestibular system (vertigo) - older: insidiously progressive myelopathy:
spastic leg weakness, axial instability, bladder impairment
10
Q
MS pattern of disease?
A
- majority of pts have resolution of initial sxs then fall into following pattern of relapsing-remitting disease - this is seen in majority of pts, interval of months to year after initial episode b/f new sxs develop or original ones reoccur
- infection, fever, and trauma precipitate or trigger exacerbations
- relapsse are more likely during 2-3 months following pregnancy (immune system is building back up)
- as disease progresses increasing disability with weakness, spasticity, ataxia, impaired vision, and urinary incontinence
11
Q
diff forms of MS?
A
- secondary progressive: clinical course changes so that a steady deterioration occurs, unrelated to acute relapses
- primary progressive disease: less common, steady progression from onset, disability develops at relatively early stage
- benign: no disability, return to normal in b/t attacks
- relapsoing-remitting: never new disaibilty b/t attacks, but after attack - baseline is worse
12
Q
How do you dx MS?
A
- complete hx and physical
- signs and sxs complaints
- neuro exam
- neuroimaging is an adjunct to clinical info:
MRI of head or cervical cord (85% clinically definite in MS pts, IV gadolinium enhances acute lesions) - clinical dx: 2 or more exacerbations greater than 2 months apart, last 24 hrs each but recover
- CT scans are not helpful and not sensitive
- if neg MRI ans suspicious - do LP - can have protein elevations, lymphocytosis, elevated IgG, myelin abs, oligoclonal bands
but tests can be altered in variety of inflamm neuro disorders and aren’t specific for MS
13
Q
Lesions of MS are? Where do they commonly occur?
A
- multifocal
- hyperintense (light up)
- occur predominantly in:
peri-ventricular white matter
corpus callosum
cerebellum
cerebellar peduncles
brainstem
spinal cord
14
Q
Definitive dx of MS?
A
- requires intermittent or progressive CNS sxs supported by evidence of 2 or more CNS white matter lesions occurring in an appropriately aged pt
- clinical picture must indicate involvement from different part of CNS at diff times
15
Q
Probable dx of MS?
A
- multifocal white matter disease but only one clinical attack, or with hx of at least 2 clinical attacks but signs of only one lesion
- preferably a neuro consult when MS suspected or confirmed
- kurtzke expanded disability status scale used to measure disease progression (0-10)
16
Q
Tx basis for MS? Tx for minimally affected pts?
A
- directed at modifying course and managing primary sxs
- minimally affected pts:
reqr no specific tx
encourage to maintain healthy lifestyle:
avoid excessive fatigue, emotional stress, viral infections, extremes of temperatures - physical therapy
17
Q
Pharm tx categories?
A
- tx acute sxs
- modify course of disease
- interrupt progressive disease
- tx continuing sxs
18
Q
What is mainstay of tx for acute exacerbations? How does it help?
A
- corticosteroids
- reduce inflammation
- improve nerve conduction
- long term admin doesn’t alter coruse of disease and can have harmful side effects
19
Q
What drugs are used to modify course of MS?
A
immune modifiers:
interferon 1a
interferon 1b
glatiramer acetate
20
Q
Drugs used for progressive MS?
A
- immunosuppressants: methotrexate (rheumatrex) cyclophosphamide (cytoxan) mitoxantrone (novantrone) azathiprine (imuran)*
21
Q
Tysabri (natalzumab) tx?
A
- lab produced monoclonal ab
- designed to hamper movemetn of potentially damaging immune cells from bloodstream across BBB into brain and spinal cord
- approved in 2006 as monotherapy for tx of relapsing forms of MS
- but it increases risk of progressive multifocal leukocephalopathy (PML - further damages myelin) - only recommended for those who have inadequate response to or can’t tolerate alt MS therapy
22
Q
sx tx of MS - spasticity?
A
- dantrolene (muscle relaxant)
- baclofen (muscle relaxant, antispasmodic)
23
Q
Sx tx of MS - fatigue?
A
- modofinil (provigil - CNS stimulant) - also used to tx hypersomnolence and narcoplepsy!
- amantadine - antiviral
24
Q
What is cerebral palsy?
A
- not caused by problems in muscles or nerves
- IT IS caused by abnormalities in parts of brain that control muscle movements
- it is a disease of childhood
- majority of children are born with it, although it may not be detected until months or years later (early signs usually appear b/f 3 - around 18 months - notic baby has deficits)
- a non-progressive disorder, but secondary orthopedic deformities such as hip dislocation and scoliosis are common
25
Diff times when cerebral palsy can occur?
- caused by damage to young developing brain
- can occur during pregnancy (75%):
infections, insufficient perinatal O2, prematurity, Rh incompatibility
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during childbirth (5%):
asphyxia during labor and delivery
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after birth (15%):
brain injuries that occur during 1st 2 years of life -
brain infections (meningitis), head traumas (trauma, child abuse)
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26
4 major classifications of cerebral palsy?
- reflect area of brain damaged
- spastic
- athetoid
- ataxic
- mixed
- in 30% of all cases - spastic form is found along with one of the other types
27
Presentation of Spastic CP?
most common type, 70%
presentation:
- damage to corticospinal tract, motor cortex or pyramidal tract
- affect nervous system ability to receive gamma amino butyric acid
- hypertonic
- spastic hemiplegias
- spastic diplegia (lower extremities are affected than upper body)
- spastic quadriplegia
28
Athetoid or dyskinetic CP?
- mixed muscle tone (hypertonia, hypotonia)
damage occurs to extrapyramidal motor system and/or pyramidal tract and basal ganglia
20% of all cases
- presentation:
have trouble holding themselves upright, steady position for sitting or walking
- often show involuntary motions
- takes a lot of work and concentration to get their hand to certain spot (scratching their nose)
- may not be able to hold onto things (toothbrush)
29
Ataxia CP
- problems with balance, especially when walking - due to damage of cerebellum, 10% (rarest form)
presentation:
- hypotonia and tremors
- motor skills like writing, typing, or using scissors might be difficult
- is common for these individuals to have difficulty with visual or auditory processing of objects and instability in balance and relation to gravity
30
All types of CP are characterized by? Most common manifestations?
- characterized by:
abnorm muscle tone, posture, reflexes, or motor development and coordination
- classical sxs:
spasticity
unsteady gait
dysarthria
soft tissue findings consist largely of decreased muscle mass
-most common manifestations include:
lack of muscle coordination when performing voluntary movements (ataxia)
- stiff or tight muscles and exaggerated reflexes (spasticity)
31
How do newborns and babies present with CP?
- floppy movements
- unable to roll over
- unable to sit, crawl or walk
- birth defects - irreg shaped spine, small jawbone or small head, sometimes occur along with cerebral palsy
32
How does CP present in older children?
- walking with one foot or leg dragging
- walking on toes, a crouched gait or a scissored gait
- muscle tone that is either too stiff or too floppy
33
Secondary sxs of CP?
- seizures
- spasms
- other involuntary movements
- speech or communication disorders
- hearing or vision impairments
- cognitive disabilities
- learning disabilities
- behavioral disorders
34
Dx of CP?
- usually takes several months to several years to dx
- most children with CP are dx around 18 months
- parents and caregivers usually first to notice
- health professional dx CP based on baby's medical hx (parents observations of developmental delays included), PE, and results of screening tests
- based on eval movements:
muscle tone - floppy or stiff
```
check reflexes:
persistence of certain reflexes called primitive reflexes that are normal in younger infants, but generally disappear by 6-12 months of age
- moro reflex - startling
- walking reflex
- rooting
- sucking
- tonic neck
- palmar grasp
- babinski
```
- see if baby has developed preference of using R or L hand until at least 12 months
- careful medical hx - attempt to rule out any other disorders
- add tests - developmental questionnaires, CT, MRI of ead, or US of brain
- US is helpful for fetal monitoring where CP may be suspected
35
Imaging findings of CP?
osseous findings mirror specific muscular deficits in a given person with CP:
- shafts of bones are often thin (gracile)
- metaphyses often appear quite enlarged (ballooning)
- articlar cartilage may atrophy, leading to narrowed joint spaces
- may exhibit a variety of angular jt deformities
- spasticity and an abnormal gait can hinder proper and/or full bone and skeletal development
- tend to be shorter in ht
- bones can gro at diff lengths, may have one leg longer than the other
36
Prognosis of CP?
- brain damage doesn't progress but sxs DO become worse
37
Tx of CP?
- can't be cured, tx often improves child's capabilities
tx may include:
PT and OT, ST
- drugs to control seizures, relax muscle spasms, and alleviate pain
- surgery to correct anatomical abnorm or release tight muscles
- braces and other orthotic devices
- wheelchairs and rolling walkers
- communication aids such as computers with attached voice synthesizers
38
What is ALS?
- incurable fatal neuromuscular disease characterized by progressive muscle weakness, resulting in paralysis
- attacks nerve cells in brain and spinal cord, motor neurons which control movement of voluntary muscles, deteriorate and eventually die. When the motor neurons die, the brain can no longer initiate and control muscle movement. Because muscles no longer receive the messages they need in order to fxn, they gradually weaken and deteriorate
- a progressive, fatal, neurodegenerative disease caused by degeneration of motor neurons in CNS that control voluntary muscle movement
39
Fxn lost in ALS?
- causes muscle weakness and atrophy throughout the body caused by degeneration of Upper and lower motor neurons
- unable to fxn, the muscles weaken and atrophy
- resulting in loss of ability to initiate and control all voluntary movement, although bladder and bowel sphincters and muscles responsible for eye movement are usually but not always spared
- cog fxn is generally spared for most pts (5% will have FTD)
- higher proportion 30-50% also have more subtle cog changes which may go unnoticed but are revealed by detailed neuropsych testing
- sensory nerves and ANS which controls fxns like sweating, are generally unaffected but may be involved for some pts
- diaphragm and intercostal muscles weaken, FV and inspiratory pressure diminish
- BIPAP used ,eventually mechanical ventilation reqd
- majority of people die of resp failure or pneumonia, death usually occurs w/in 2-5 years after initial dx
40
Who does ALS affect?
- can strike at any age, most people b/t 40-70 when disease strikes and men are affected slightly more frequently than women
- est 5000 people in US are dx with disease each year
41
Cause of ALS?
- known hereditary factor in familial ALS, where condition is known to run in families, although it only accounts for 5% of all cases
- for pts w/o family hx of disease - 95% of cases, mo known cause
- some enviro causative factors - suggestive for increased incidence in western pacific
- military veterans are at increased risk (neurotoxic chemical exposure?) - gulf war or could be CTE that mimics ALS
42
Earliest sxs of ALS?
- obvious weakness or muscle atrophy
- other presenting sxs:
muscle fasciculation (twitching), cramping, or stiffness of affected muscles, muscle weakness affecting an arm or a leg, and or slurred and nasal speech
- parts of body affected by early sxs of ALS depend on which motor neurons are damaged first
- aboud 75% of people contracting disease experience limb onset ALS first - upper limb or lower limb (may experience awkwardness when walking or running or notice they are tripping or stumbling often with dropped foot)
arm onset - difficulty with tasks such as buttoning a shirt or writing
43
Bulbar onset ALS?
- 25% of cases
- worse prognosis
- pts first notice difficulty speaking clearly or swallowing. Speech may become slurred, nasal in character or quieter
- other sxs include difficulty swallowing and loss of tongue mobility, smaller proportion of pts experience respiratory onset ALS where intercostal muscles that support breathing are affected first
44
Dx of ALS?
- to be dx pts must have signs and sxs of both upper and lower motor neuron damage that cant be attributed to other cases
- no test can provide definitive dx
- dx primarily based on sxs and signs physician observes in pt and series of test to rule out other diseases
- obtain full hx and usually conduct neuro exam at regular intervals to assess whethere sxs such as muscle weakness, atrophy, hyper-reflexia and spasticity are getting worse
45
Neuro testing?
- EEG
- EMG: support dx
- nerve conduction velocity: specific abnorm in NCV reslts may suggest for example, that pt has form of peripheral neuropathy or myopathy rather than ALS
- MRI: usually normal can be used to rule out other diseases
46
Progression of ALS?
- most pts eventually aren't able to walk, or stand, use hands or arms
- have difficulty swallowing and chewing, increase choking, maintaining wt a problem
- pts usually don't have problem with cognitive abilities so aware of progressive loss of fxn - may become anxious and depressed
- a small percentage go on to develop FTD
- larger proportion experience mild problems with word generation, attention and decision making
47
Slowing progression of ALS?
- FSA approved only one drug tx:
- riluzole (rilutek):
reduce damage to motor neurons by decreasing the release of glutamate via activation of glutamate transporters
- may offer other neuroprotective effects, by means of Na+ and Ca++ channel blockades, inhibition of protein kinase C and promotion of NMDA receptor antagonism
- doesn't reverse damage already done to motor neurons
48
Clinical trials with ALS pts and riluzole?
- lengthens survival by several months, may have greater survival benefit for those with bulbar onset
- drug also extends time before pt needs ventilation support - pts must be monitored for liver damage while on this drug
49
What is Wernicke-Korsakoff syndrome? Caused by?
- results from chronic alcoholism
| - caused by deficiency of thiamine (vitamin B1)
50
Characteristics of Wernicke-Korsakoff syndrome?
- confusion
- amnesia
- confabulation (most distinguishing feature - fill in memory with imaginary events)
```
- other features:
acute weakness
paraylsis of EOMs
nystagmus
ataxia
peripheral neuropathy
diplopia
```
51
Diff for wernicke-korsakoff syndrome?
- temporal lobe epilepsy
- temporal lobe infarction
- concussive head injury
- transient global amnesia
- anoxic encephalopathy
- alzheimer disease
- 3rd ventricle tumore
- herpes simplex virus sequela
52
How do you dx Wernicke-Korsakoff syndrome?
- sxs
- CBC (to r/o infection)
- Coags (r/o bleeding disorder)
- serum/urine drug test (toxins)
- liver enzymes
- CT scan - rule out hemorrhage
- *MRI: will show acute lesions of wernicke's
53
Tx of Wernicke-korsakoff syndrome?
- supplemental thiamine, usually by starting with an initial IV or IM dose followed by supplemental po doses
- it is impt to start thiamine tx before giving any glucose as encephalopathy will be worsened by glucose
