030215 infectious dis of nerv sys

Question 1

types of infection in nervous system

Answer 1

leptomeningeal inflammation (meningitis-pia and arachnoid)

parenchymal inflam (encephalitis/cerebritis/myelitis (sp cord) or brain abscess)

subdural or epidural inflam (empyemas)

Question 2

routes of infection entrance into brain

Answer 2

hematogeneous spread
local extension (air sinuses, infected tooth)
neural route (PNS to CNS)
direct implantation

Question 3

clinical signs of meningitis

Answer 3

headache
photophobia
stiff neck 
clouded consciousness
fever

Question 4

types of meningitis

Answer 4

hyperacute (under 24 hrs)
acute (2-7 days)-most common
subacute or chronic (over 1 wk)
aseptic

Question 5

hyperacute meningitis is usually caused by

Answer 5

meningococcal meningitis (neisseria mening)
sparse inflam

Question 6

acute meningitis is usually caused by

Answer 6

bacteria

usually from hematogenous spread

Question 7

subacute meningitis is usually caused by

Answer 7

TB, syphilis (often brain parenchyma also affected)

lymphocytes, plasma cells, macrophages appear in exudate

Question 8

aseptic meningitis is usually caused by

Answer 8

viruses. much less severe than bacterial causes.

summer, early fall
lymphocytic infiltrate in meninges

Question 9

how are brain abscesses unique

Answer 9

they form fibrous wall (usually, in brain healing, there’s just gliosis)

Question 10

causes of brain abscesses

Answer 10

usually bac or fungal:

immunocompetent–strep, staph
immunocompromised-toxoplasma, nocardia, isteria, gram neg bacilli, mycobacteria, fungi

Question 11

causes of bacterial meningoencephalitis

Answer 11

TB
syphilis
Lyme dis

Question 12

causes of encephalitis

Answer 12

bacteria
viruses
fungi

Question 13

what abnormalitiy would you detect for TB induced meningoecphalitis

Answer 13

CSF has elevated pressure and protein, decreased glucose, lymphocytic pleocytosis (increased lymphocyte count)

AFB stain may show bacteria

Question 14

tuberculoma

Answer 14

mass lesion w central necrotic core of caseation, surrounded by fibroblasts epitheliloid histiocytes, giant cells and lymphocytes

AFB are present in necrosis

Question 15

what pathological findings can be present for TB infec

Answer 15

tuberculoma

tuberculosis osteomyelitis

Question 16

major forms of syphilis-clinical

Answer 16

general paresis (thickened meninges, atrophic brain, impairment of cognition

meningovascular (like TB) (occlusion of vessels, focal neuro deficits)

tabes dorsalis (dorsal columns of sp cord)

Question 17

tabes dorsalis

Answer 17

chronic inflam in dorsal roots and ganglia w loss of neurons and associated degeneration of posterior columns (axons and myelin)

Question 18

causes of viral meningoencephalitis

Answer 18

arboviral encephalitis
herpes virus (HSV1, HSV2, CMV, VZV)
HIV
progressive multifocal leukoencephalopathy

Question 19

mood, memory, behavior abnormalities

Answer 19

HSV1 infection

Question 20

arboviral meningoencephalitis

Answer 20

important cause of epidemic encephalitis (West Nile, equine, etc)

Question 21

classic lesion for HIV encephalitis

Answer 21

microglial nodule containing multinulceated microglial cells that contain HIV virus (look at the slide)

Question 22

progressive multifocal leukoencephalopathy

Answer 22

occurs in immunosuppressed pts
caused by JC virus
infects oligodendrocytes