CNS infections

Question 1

sites/types of bacterial infections

Answer 1

• scalp, sinus, or ear infection - osteomyelitis - epidural abscess - leptomeningitis aka meningitis - brain abscess - encephalitis

Question 2

pathology of acute bacterial meningitis shows

Answer 2

subarachnoid space filled with neutrophils, bacteria, necrotic debris

Question 3

pathogenesis of bacterial meningitis

Answer 3

Direct extension or bacteremia

Question 4

________ of a parameningeal cranial infection from the mastoid air cells, paranasal sinuses, skull, etc.

Answer 4

direct extension

Question 5

a hematogenous dissemination of the bacteria

Answer 5

Bacteremia

Question 6

clinical signs of acute bacterial meningitis

Answer 6

presents clinically with fever, headache, stiff neck, and mental status changes

Question 7

meningeal inflammation means

Answer 7

stiff neck and headache

Question 8

communicating hydrocephalus

Answer 8

the obstruction is within the subarachnoid space or arachnoid vili

Question 9

non communicating hydrocephalus

Answer 9

the obstruction is within the ventricular system

Question 10

type of bacterial infection in meningitis is ___ dependent

Answer 10

age

Question 11

neonate bacterial meningitis infectious agents

Answer 11

Group B strep, Listeria, enteric bacilii

Question 12

agents that cause bacterial meningitis in children

Answer 12

S. pneumonia, N. meningitidis, H. influenzae

Question 13

agents that cause bacterial meningitis in adults

Answer 13

S. pneuomiae, N. meningitidis

Question 14

onset of acute meningitis

Answer 14

hours to days

Question 15

onset of subacute/chronic meningitis

Answer 15

weeks to months

Question 16

Organisms associated with subacute/chronic meningitis include

Answer 16

mycobacteria (tuberculosis), fungi (cryptococcosis), and spirochetes (syphilis, Lyme disease)

Question 17

idiopathic cause of meningitis

Answer 17

sarcoidosis

Question 18

Granulomatous inflammation, mainly involving base of brain, causing brain infarcts from verse involvement

Answer 18

tuberculous meningitis

Question 19

tuberculous meningitis can cause ____ mainly involving the base of the brain

Answer 19

granulamtous inflammation

Question 20

Answer 20

multinucleate giant cells in the granuloma

Question 21

stain of tuberculous meningitis

Answer 21

acid fast stain

Question 22

common cause of brain infection in immunocompromised individuals

Answer 22

cryptococcosis

Question 23

macroscopic findings of cryptococcosis

Answer 23

»Meninges thickened/opacified

»Slimy consistency

»Yellow-gray exudate in ventricles/perivascular spaces in immunocompromised.

»Subacute cases produce leptomeningeal fibrosis

• multiple small cysts in brain

Question 24

subactue cryptococcosis cases produce _______ fibrosis

Answer 24

leptomeningeal fibrosis

Question 25

50% cases show multiple _______ (“soap bubbles”) secondary to exuberant capsular material in brain (basal ganglia)

Answer 25

intraparenchymal cysts

Question 26

tuberculous meningitis can result in brain infarcts from vessel invovlement, leading to _____ damage and meningeal fibrosis. Meningeal fibrosis can cause \_\_\_\_\_\_\_\_.

Answer 26

- cranial nerve damage - hydrocephalus

Question 27

microscopic findings on cryptococcosis

Answer 27

- single budding yeast forms - surrounded by thick capsule, may shrink in tussue prep and leave "halo" around organisms - leptomeningeal inflammation: lymphocytes, plasma cells, gianet cells

Question 28

Types of neurosyphilis

Answer 28

- subacute leptomeningitis - chronic leptomeningitis with associated vasculitis and vasculopathy (meningovascular syphilis) - chronic spinal arachnoiditis with degerneration of dorsal roots and the posterior columns of the spinal cord (tabes dorsalis) - chronic low grade encephalitis - congenital neurosyphilis

Question 29

what is this

Answer 29

brain abscess

Question 30

pathogenesis of brain abscess

Answer 30

1. direct extension 2. implantation following head trauma 3. bacteremia from distant focus of infection

Question 31

direct extension from a parameningeal (cranial infection) can come from the _____ and cause a frontal lobe abscess

Answer 31

paranasal sinuses (sinusitis)

Question 32

direct extension from a parameningeal (cranial infection) can come from the __________ and cause temporal-lobe or cerebellar abscess

Answer 32

middle ear or mastoid air cells (otitis or mastoiditis)

Question 33

Direct extension may also cause an epidural abscess, subdural empyema, or \_\_\_\_\_\_

Answer 33

leptomeningitis

Question 34

bacteremia often creates how many brain abscesses?

Answer 34

multiple

Question 35

location of abscesses in brain

Answer 35

preferentially localizes to the gray-white junction

Question 36

focus of cerebritis after penetration of BBB by bacteria happens within ____ days

Answer 36

4-9 days

Question 37

formation of fibrous capsule happens day ____ in pathogenesis of a brain abscess

Answer 37

day 14

Question 38

a brain abscess typically presents as a \_\_\_\_\_\_\_

Answer 38

mass lesion

Question 39

in brain abscess, Patient may also have fever or \_\_\_\_\_\_\_.

Answer 39

leukocytosis

Question 40

clinical consequences of mass effect

Answer 40

- headache, nausea, and vomiting from increased ICP - potential for herniation

Question 41

a brain abscess causes local brain destruction that may result in \_\_\_\_\_\_\_\_\_\_

Answer 41

neurological deficits

Question 42

A diffuse inflammation of brain

Answer 42

encephalitis

Question 43

A diffuse inflammation of brain and spinal cord

Answer 43

encephalomyeiltis

Question 44

most common cause of encephalitis

Answer 44

viruses

Question 45

common viruses that cause encephalitis

Answer 45

- HSV 1 and other herpesviruses - arboviruses - HIV - rabies - enteroviruses

Question 46

Hematogenous Pathogenesis of CNS viral infection

Answer 46

from viremia after initial viral replication in GI tract (enteroviruses) or innoculation site (arboviruses)

Question 47

when viremia travels and infects leptomeningeal cells it causes

Answer 47

Stiff neck, headache, & fever; lymphocytic leptomeningitis

Question 48

infectino of cells in the brain (viral encephalitis) causes

Answer 48

Headache, coma, seizures, & fever; lymphocytic infiltrates & brain necrosis

Question 49

pathogenesis of viral infection can also be spread along axons by \_\_\_\_\_\_\_\_\_

Answer 49

retrograde spread

Question 50

HSV1 infection of oral cavity retrograde spread of virus goes to the ______ gangiion

Answer 50

trigeminal

Question 51

HSV 1 encephalitis primary involves the ____ and ____ lobes after infection

Answer 51

temporal and inferior frontal lobes

Question 52

initial infection of HSV1 occurs in ______ of cases and reactivation later occurs in ______ of cases

Answer 52

30% 70%

Question 53

viral trophism of poliovirus

Answer 53

anterior horn cells

Question 54

viral trophism of JC virus

Answer 54

oligodendrocytes - progressive multifocal leukoencephalopathy

Question 55

viral trophism of rabies virus

Answer 55

— hippocampus and cerebellum

Question 56

viral trophism of Varicella-Zoster virus

Answer 56

— dorsal root ganglia

Question 57

viral trophism of Lymphocytic choriomeningitis virus —

Answer 57

leptomeninges