the nervous system

most common cause of dementia in young adults: called AIDS-dementia complex. 60% of individual with aids develop neurologic dysfunction

HIV

this is the most common cause of sporadic viral encephalitis:

HSV 1

this occurs in neonates born to women with this disease anc can cause viral encephalitis:

HSV 2

one of the major manifesttaions of neurosyphilis is meningeal, called this:

meningovascular neurosyphilis

an example of demyelinating disease. is autoimmune, most common disorder of myelin. is environmental and genetic that result in a loss of tolerance to self proteins (MYELIN ANTIGENS).

multiple sclerosis

these are bundles of paired helical filaments in the cytoplasm of the neurons that displace or encircle the nucleus.

neurofibrillary tangles

a type of chronic meningitis, is a tertiary stage of syphilis and occurs in only about 10% of individuals with untreated infection.

neurosyphilis

this is caused by invasion f the brain by TREPONEMA PALLIDUM and manifests as insidious but progressive loss of mental and physical functions with mood alterations, terminating in severe dementia.

paretic neurosyphilis

this is a clinical syndrome charcterized by diminished facial epression (masked facies), stooped posture, slowness of voluntary movement, festinating gait (progressively shortened, accelerated steps), rigidity, and a "pill rolling" tremor. this type of motor disturbance is seen in a number of conditions that share damage to dopaminergic neruons of the substantia nigra or to their projection to the striatum.

parkinsonism

these contain a central core of amyloid with or without a surrounding region of dystrophic neurites and tangles:

plaques

at the microscopic level, alzheimer disease is dagnosed by the presence of these: (a type of extracellular lesion), and this (a type of intracellular lesion)

plaques and neurofibrillary tangles

these are caused by rupture of a small intraparenchymal vessel. hypertenison is the most common cause.

primary brain parenchymal hemorrhage

this group of disease includes sporadic, familial, iatrogenic and variant forms of creutzfeldt-jakob disease (CJD). several animal disease from this group are known (mad cow).

prion disease (spongiform encephalopathies)

this disease is also called SPONGIFORM ENCEPHALOPATHIES because of the presence of microscopic vacuolation ("spongiosis") that develops with the cell bodies of nerons and in the surrounding neuropil in most cases

prion diseases

all these prion desease disorders are associated with abnormal forms of a normal cellular protein, termed this:, which can act as an infectious agent, since it propagates itself and injures the cells in whichit is present

prion protein (PrP)

this is transmitte dto humans by the bite of a rabid animal. virus enters the CNS by ascending along the peripheral nerves from the wound site. the patient shows extraordinary CNS excitability. periods of alternating mania and stupor progress to coma and death from respiratory failure:

rabies

the most frequent cause of clincially significant subarachnoid hemorrhage is rupture of this:. this is a thin walled out pouching of an artery

saccular (berry) aneurysm

this is the clinical designation othat applies to all three of these conditions:

stroke

in addition to pernicious anemia, deficiency of vitamin B12 may lead to this:, which is associated with patchy losses of myelin of the spinal cord. starts with tingling in lower extremities, but can progress to complete paraplegia:

subacute combined degeneration of the spinal cord

veins that extend from the cerebral hemispheres through the subarachnoid and subdural space empty into dural sinuses. these are prone to tearing and their disruption leads to this.

subdural hematoma

this is another form of neurosyphilis, resulting from damage to the sensory nerves in the dorsal roots producing impaired joint position sense and resultant ataxia

tabes dorsalis

name the 3 categories of meningitis:

1. acute pyogenic (bacterial) 2. aspetic meningitis (viral) 3. chronic

VASCULAR MALFORMATIONS of the brain are classified into 4 principal types based on the nature of the abnormal vessels:

1. arteriovenous malformations (AVM)-most common and most likely cause of hemorrage 2. Cavernous angiomas 3. capillary telangiectasias 4. venous angiomas

name the 3 traumatic parenchymal injuries:

1. contusion 2. diffuse axonal injury 3. concussion

vascular injury is a frequent component of CNS trauma and may occur in any of several compartments: name the compartments:

1. epidural 2. subdural 3. subarachnoid 4. intraparenchymal

name 2 metabolic and toxic disturbances of neurologic disease

1. thiamine deficiency 2. vitamin B12 deficiency

the three basic processes or the way cerbrovascular disease occurs is this:

1. thrombotic occlusion of vessels 2. embolic occlusion of vessels 3. vascular rupture

accumulation fo this in the brain initiates a chain of events that result in the morphologic hanges of alzheimer disease and ementia. it is derived from a larger membrane protein known as "amyloid precursor protein (APP)", which is processed in either of two ways.

Beta amyloid, or alpha beta.

occurs in neonatal or immunocompromised including AIDS patients, can cause viral encephalitis:

CMV

causes :Progressive Multifocal Leukoencephalopathy". the disease occurs invariably in immunocompromised patients including AIDS patients. affects oligodendroglia, resulting in demyelination:

JC virus

brain infarctions are sometimes preceded by transient episodes of neurologic dysfunction lasting from several minutes up to 24 hours. these episodes are termed this: and are caused by self limited episodes of vascular obstruction by atheromatous emboli. are important predictors to infarcts.

TIAs-transient ischemic attacks

in this, patients typically show systemic signs of infection superimposed on clinical evidence of meningeal irritations and neurologic impairment-including headache, photophobia, irritability, clouding of consciousness, and neck stiffness. bacteria may be seen aon a smear or cultured from CSF. this can be fatal if not treated.

acute pyogenic meningitis (bacterial meningitis)

this is the most common cause of demntia in the elderly. disoreintation, mood and behaviour changes, aphasia, disabled, mute, immobile. most cases are sporadic, but 5-10% are familial.

alzheimer disease

this is the most common form of neurodegeneration affecting the motor system. it is characterized by muscle atrophy ("amyotrophy") and hyper reflexia due to loss of both uppe and lower motor neurons. some are familial, involving the gene encoding a form of superoxide dismutase, SOD1. body becomes paralysed with progression, howerver intelligent levels are not affected. may invlve respiratory muscles, leading to recurrent bouts of pulmonary infection which causes death. (stephen hawkings)

amyotrophic lateral sclerosis (Lou Gehrig's Disease)

most common cause of epidemic encephalitis, occurs in the late summer when mosquitoes are most abundant (is insect born)

arbovirus

this is a misnomer. it is a clinical term for an illness comprising meningeal irritation, fever, and alterations of consciousness of relatively acute onset without recognizable organisms. is less fulminant thatn pyogenic meningitis. in most cases, a pathogen can eventually be idnetified, most commonly an enterovirus.

aseptic meningitis (viral meningits)

these represnt the most common group of primary CNS tumors

astrocytoma

these are nearly always caused by bacterail infections, can arise by direct implantation of organisms, local extension from adjacent foci, or hematogenous spread (heart, lungs, distal bones or after tooth extraction). they are destructive lesions and exhibit general signs of raised intracranial pressure.

brain abscesses

this is the most common cause of brain infacts

cerebral atherosclerosis

this is the 3rd leading cause of death. it denotes any abnormaility of the brain caused by a pathologic process involving blood vessels.

cerebrovascular disease

in neurosyphilis (tabes dorsalis), the loss of pain sensation, leading to skin and joint damage is called:

charcot joints

meningitis is usually an infection, but chemicals can do this also which is called:

chemical meningitis

several pathogens are associated with this, and there may also e a parenchymal component of the disease. long lasting meningitis

chronic meningitis

this describes reversible altered consciousness from head injury in the absence of contusion. the characteristic transient neurologic dysfunction includes loss of consciousness, temporary respiratory arrest, andloss of reflexes. amnesia for the event persists.

concussion

multiple aneurysms are sometimes referred to as this, but they are not present at birth but develop over time because of underylying defects in the vessel media

congenital

these occur when the brain collides w/ the skull during head injury. is caused by rapid tissue displacement, disruption of vascular channels, and subsequent hemorrhage, tissue injury, and edema:

contusions

this is a rare but well characterized prion disease that manifests clincially as a rapidly progressive dementia. it is sporadic in about 85% of cases, familial forms also exhist.

creutzfeldt-jakob disease (CJD)

a group of disease where normal myelin is broken down for inappropriate reasons, often by inflammatory processes

demyelinating diseases

these are characterized by widespread injury to axons within the brain. the movemnt of the brain relative to another region of the brain is thought to impact it and cause injury

diffuse axonal injury

these are a group of disease that are metabolic and the underlying structure of the myelin is abnormal or its turnover is abnormal

dysmyelinating disease (was never normal)

these are relatively rare. within the skull, such lesions usually occur as a complication of primary infection in the paranasal sinuses or mastoid or as a consequence of trauma.

epidural and subdural infections. ()epidural infections in this region tend to remain localized, whereas those involving the subdual space may spead widely.)

this may expand rapidly and is a neurosurgical emergency requiring prompt drainage. vessels that run in the dura, most importantly the middle meningeal artery, are vulneralbe to this injury, particularly with skull fractures.

epidural hematoma

this is where cerebral arterial occlusion leads to focal ischemia and infarction of CNS tissue.

focal cerebral ischemia

these are tumors of the brain parenchyma that histologically resemble different types of glial cells. major tumors of this category are astrocytomas, oligodendrogliomas, and ependymomas.

gliomas

this pattern of widespread ischemic/hypoxic injury occurs when there is a generalized reduction of cerebral perfusion, usually below systolic pressures of less than 50mmHg. clinical outcome ranges from a transient postischemic confusional state to brain death with diffuse cortical injury and brain stem damage

global cerebral ischemia

an inherited autosomal dominant disease characterized clinically by progressive choreiform, involuntary jerky movemnt and dementia. is relentlessly progressive, resulting id death after an average course of about 15 years. onset is related to the length of the trinucleotide repeat. increased suicide rate, w/ intercurrent infection being most common death.

huntington disease

this is the most common neurodegenerative disease associated with parkinsonism. absence of a toxic or other knonw underyling etiology and if they show clinical response to 1-dihydroxyphenylalanine (1-DOPA) they may be diagnosed with this:

idiopathic parkinson disease

in thiamine deficiency, the acute stages, if unrecognized and untreated, may be followed bya prolonged and largely irreversible condition called:, associated with profound memory disturbances

korsakoff syndrome

these are inherited diseases associated with mutations affecting the proteins required for formation of normal myelin or in mutations that affect the synthesis or degradation of myelin lipids. motor skill deterioration, spasticity, hypotonia, or ataxia can be seen.

leukodystrophies

in tabes dorsalis, the term for impaired joint postiton sense and resultant ataxia is:

locomotor ataxia

these occur predominantely in children and exclusively in the cerebellum. the tumor is often largely undifferentiated. is highly malignant, but is exquisitely radiosensitive.

medulloblastoma

these are predominantly benign tumors of adults, usually attached to the dura, and arising from the meningothelial cells that invest the arachnoid mater. most lesions of this occur outside the brain parenchyma.

meningiomas

this is an inflammatory process of the leptomeninges and CSF within the subarachnoid space.

meningitis

(this develops with spead of the infection from the meninges into the underlying brain)

meningoencephalitis

starting in 1995, a series of cases with a CJD-like illness appeared in the UK. they differed from typical CJD in several importan respects. the disease affected young adults and the neuologic syndrome progressed more slowly.

variant creutzfeldt-jakob disease

this is a parenchymal infection of the brain that is almost invariably associated with meningeal inflammation, and therefore is better termed MENINGOENCEPHALITIS.

viral encephalitis

in addition to the systemic effects of thiamine deficiency (beriberi), there may also be abrupt development of confusion, abnormalities in eye movement and ataxia, a syndrome termed this:

wernicke encephalopathy

because wernicke encephalopathy and korsakoff syndrome syndromes are closely linked, this term is often used:

wernicke-korsakoff syndrome