Week 2 - Part 2 Flashcards
(23 cards)
Multiple Sclerosis
most common demyelinating disease of CNS
demyelination is multifocal,, disseminated in time and space
more female, 20-40yo, northern climates
classic type to rapidly progressive (Marburg or Balo’s)
Path: plaques of demyelination usually in periventricular or optic nerves
plaquesc can be active (macrophages, lymphocytes), inactive (myelin loss with axons preserved), or shadow (partial)
Mechanism: autoreactive CD4(MHC-II) T-cells (for MBP, MOG, PLP)
breakdown of BBB, infiltration of immune cells, de/remyelination, gliosis, axonial degeneration
maybe also reactive oxygen, antibody-mediated, or excitotoxicity
Clinical courses: relapsing-remitting, secondary progressive, primary progressive, progressive relapsing
Clinically isolated syndrome (CIS) may be indicative of MS, likelyhood based on lesions on MRI
Acute disseminated encephalomyelitis (ADEM)
monophasic demyelinating disease with acute onset
recent viral illness prodrome
more in children
headache, lethargy, coma (very ill)
most completely recover, high-dose steroids
Path: Perivenous demyelination with axons preserved,, MRI shows multiple extensive lesions, CSF has increased WBCs
T-cell mediated hypersensitivity
Neuromyelitis optica (Devic disease)
relapsing synchronous bilateral optic neuritis and spinal cord lesions
more females, asians
severe vision loss
Path: necrosis, demyelination, inflam cells
AQP4 IgG antibodies
Central pontine myelinolysis
(Osmotic demyelination syndrome)
monophasic loss of myelin in base of pons, can be extrapontine too
limb weakness, gaze, speech,, neuropsychiatric and neurologic sx
assoc with too rapid correction of hyponatremia
tx is to recreate the original osmotic state, correct slowly
Demyelinating Optic neuritis
inflammatory optic neuropathy
assoc with MS (may be early sign)
acute vision loss, pain worse with eye movement, decreased color vision
usually recover well rapidly, good long-term prognosis
Transverse Myelitis
acute or subacute myelopathy accompanied with indicators of inflammation
combo of sensory, motor and bladder/bowel sx
Lhermitte sign, paroxysmal tonic spasms
complete= monophasic, symmetric severe loss
Incomplete= patchy involvement, more likely MS
Major events in human brain devo
Neurulation- 3-4wk- neural tube, PNS, leptomeninges
Prosencephalic- 2-3mo- paired cerebral hemispheres, other shapes
Neuronal prolif- 3-4mo- neurons in cerebrum
Neuronal migration- 3-5mo- layered cortex
Organization- 5mo– organization
Myelination- birth– “top” first, then the rest by 2yo
Neural tube defects
disturbance of formation of neuroectodermal or overlying mesodermal structures
trisomies, FOLIC ACID def, etc, valproic acid
high maternal AFP on screen
Spina bifida= occulta(mild) or cystica (meningocele or myelomeningocele, complications- hydrocephalus, chiari II)
anencephaly= die within days
encephalocele= pedunculated masses of cerebral tissue and dura protruding through cranial defect, covered by skin, usually occipital,, Meckel-Gruber syndrome
Disorders of migration and sulcation
Polymicrogyria= too many small fused gyri, disordered neuron organization, caused by intrauterine ischemia, focal or diffuse
Agyria (lissencephaly)= absence of gyri, neurons only migrate part way
Pachygyria= fewer broad gyri, small brain, Miller-Dieker syndrome
Schizencephaly= uni or bilateral clefts within cerebral hemispheres, abn morphogenesis
Disorders of cleavage of forebrain
Arrhinencephaly:
-Holoprosencephaly= craniofacial defect,, can be alobar, semilobar, or lobar
-Olfactory aplasia
due to sporadic failure in 4-6wk gestation
auto dom form with SHH gene
Agenesis of corpus callosum
due to insult to commissural plate during embryogenesis
no cingulate gyrus either
Probst bundles
can be asymptomatic (except on particular language tests)
assoc with other probs, Aicardi syndrome (females)
Chiari malformations
Type 1= chronic tonsillar herniation, assoc with hydrocephalus, 90% also have syringomyelia
Type 2= herniated cerebellar tissue through formen magnum, causes hump in brainstem/spinal cord,, assoc with myelomeningocele,, lowe CN defects,, vitA deficiency
Malformations of the cerebellum
Dandy Walker malformation= agenesis of the vermis, hydrocephalus,, assoc with isotretinoin
Syringomyelia
fluid filled cleft-like cavity in spinal cord
assoc with chiari type 1
also seen post-trauma
progressive loss of pain/temp/vibration/motor
Perinatal hypoxic/ischemic/hemorrhagic lesions
Hypoxic/ischemic=
-white matter necrosis (periventricular leukomalacia)- sharpy defined foci of necrosis in WM, common in premies, selectively vulnerable oligos
-gray and white matter (multicystic encephalopathy)- 3rd trimester, sponge-like cysts remain, caused by extensive ischemia
Hemorrhagic= subependymal germinal plate hemorrhage- often break through into ventricular system, related to extreme physical distress (premature)
Perinatal insults cause Cerebral palsy, non-progressive neurologic motor deficits
8 points of mental status exam
Appearance/attitude/behavior speech (rate, rhythm, tone) mood(subjective)/affect(objective) thought form/process and content perception (hallucinations) sensorium/cognition insight (self awareness/reflection) judgement
A snake moves toward prey silently in jungles
Kraepelinian triad for mania
elation
flight of ideas
increased psychomotor activity
Diagnosing a manic episode
distinct period, at least one week
persistently elevated, expansive mood (or irritable)
also 3 of: gradiosity, decreased need for sleep, hyperverbal, racing thoughts, distractibility, psychomotor agitation, pleasurable activity with painful consequences
Stages of mania
1: (acute) increased psychomotor, labile mood, tangential thought, sexual preoccupation, high but not out of control
2: (delusional) more pressured speech, depression, hostility, assaultive behavior, delusions
3: (delirious) desparate, panic, frenzied, bizarre, hallucinations, disorientation
Medication for Bipolar
Lithium (cheapest)
anti-seizure (carbamazapine, valproate, lamictal, clonazepam)
neuroleptics/antipsychotics (aripiprazole, chlorpromazine, olanzipine, quetiapine, risperidone, ziprasidone)
antidepressants
omega-3 fatty acids
Diagnosing major depressive episonde
depressed mood or loss of interest or pleasure
+ 4 of: weight change, sleep change, psychomotor change, fatigue, worthless, guilt, decreased concentration, suicidal thoughts
Also NOT: mixed episode, substance abuse, or bereavement
Stages of bereavement
shock (numbness, crying, denial)
preoccupation with the deceased (guilt, anger, sadness)
resolution
Drugs for depression
tricyclics (1st line, sides= dry mouth, sedation, ortho hypotension)
SSRIs (harder to dose, sides= headache, nausea, insomnia, anxiety, sex drive)
atypicals
MAOIs
others
