CNS infections

Question 1

what are the main causative organisms in viral encephalitis ?

Answer 1

HSV
chicken pox measles
Enterovirus

Question 2

bacterial meningitis can be classified into?

Answer 2

acute pyogenic meningitis
chronic meningitis

Question 3

localized bacterial infections can be classified into

Answer 3

abscess
empyema

Question 4

what are the main causative organisms of acute pyogenic meningitis ?

Answer 4

E.coli or group B streptococci ( in infants)
Neisseria meningitides ( young adults)
streptococcus pneumonia ( older patients)

Question 5

what is the main causative organism in chronic meningitis ?

Answer 5

mycobacterium tuberculosis

Question 6

what are the CNS infections caused by viruses ?

Answer 6

acute aseptic meningitis
encephalitis
brain stem and spinal cord syndrome

Question 7

what is meningitis ?

Answer 7

an acute inflammatory process involving the leptomeninges ( arachnoid and pia mater)

Question 8

what is the degree of exudate extension in meningitis ?

Answer 8

it may extend into the perivascular virchow robin spaces
however direct extension into the brain is rare

Question 9

what are the types of infectious meningitis ?

Answer 9

acute pyogenic
aseptic
chronic

Question 10

how can you differentiate between the various subtypes of infectious meningitis ?

Answer 10

CSF examination

Question 11

what are the bacteria most commonly causing bacterial meningitis?

Answer 11

Children under 10 years:
streptococcus pneumoniae
neisseria meningitides
Newborn period:
Group B streptococci
E.coli and listeria
Adults:
streptococcus pneumonia

Question 12

what is the gross picture in acute pyogenic meningitis ?

Answer 12

evident purulent exudate within leptomeninges on the surface of the brain , sulci are obscured by the exudate

Question 13

what are the typical CSF findings in in acute bacterial meningitis?

Answer 13

low glucose
high protein
high cell count with many PMN
Lactate dehydrogenase is also increased with bacterial meningitis

Question 14

how do we obtain a CSF sample ?

Answer 14

through a lumbar puncture

Question 15

what do we have to check before proceeding with a lumbar puncture ?

Answer 15

we have to check for papiloedema ( increased intraocular pressure) this means that intracranial pressure is too high to safely perform a lumbar puncture

Question 16

what are the typical CSF findings in viral infections?

Answer 16

low white blood cell count
predominance of lymphocytes
normal to elevated protein levels
CSF to glucose ratio is usually normal

Question 17

what are the CSF findings in fungal infections ?

Answer 17

predominance of lymphocytes
elevated protein levels
low glucose levels

Question 18

what are the CSF findings in tubercular infections?

Answer 18

predominance in lymphocytes
elevated protein levels
low glucose levels

Question 19

what are the classifications of CNS tuberculosis ?

Answer 19

Intracranial
spinal

Question 20

chronic meningitis?

Answer 20

TB

Question 21

what is tuberculous encephalitis ?

Answer 21

a syndrome exclusively present in infants and children

Question 22

what is the presentation of tuberculous encephalitis ?

Answer 22

comes in the form of stupor, convulsions , coma but without meningeal irritation or focal neurological deficit

Question 23

gross picture of a tuberculoma?

Answer 23

well circumscribes greyish white lesion with some fibrous encapsulation

Question 24

what would you find microscopically in a tuberculoma ?

Answer 24

giant cells
caseous necrosis
epitheliod cells

Question 25

what stain is used to identify TB

Answer 25

Zeihl neilson acid fast stain

Question 26

what kind of necrosis occurs with brain abscess ?

Answer 26

liquefactive necrosis

Question 27

what is a tuberculous brain abscess ?

Answer 27

an encapsulated collection of pus containing viable tubercular bacilli without a definite tubercular granuloma

Question 28

what would the microbiology of the tuberculous brain abscess show ?

Answer 28

TB bacilli

Question 29

what is the gross presentation of cryptococcal meningitis ?

Answer 29

Cerebral cortex shows multiple small cyst-like structures throughout the gray and white matter (soap bubble lesions)

Question 30

what do the cyst like structures in cryptococcal meningitis correspond to ?

Answer 30

corresponding to dilated perivascular (Virchow-Robin) spaces

Question 31

what do the 'soap bubble lesions' contain ?

Answer 31

contain mucoid material characteristic of Cryptococcal meningitis

Question 32

inflammatory response in cryptococcal meningitis ?

Answer 32

barley

Question 33

what are the characteristic location involvement in HSV encephalitis ?

Answer 33

inferior and medial temporal lobes

Question 34

what damage does HSV produce in the cerebral cortex?

Answer 34

hemorrhagic meningoencephalitis , The virus directly infects cells in the cerebral cortex, causing necrosis and a glial reaction

Question 35

what are the layers surrounding BV in HSV encephalitis ?

Answer 35

BV surrounded by lymphocytic infiltration which surrounded by haemorrhage causing necrosis

Question 36

how do CNS infections reach intracranial structures?

Answer 36

through hematogenous spread direct extension from nearby structures direct source ; trauma injury

Question 37

if we want to give empirical ab what to give ?

Answer 37

3rd generation cephalosporins ( cetriaxone)

Question 38

what ab to give with a confirmed case of meningococci meningitis ?

Answer 38

Penicillin G

Question 39

what are the antimicrobial prophylaxis required for close contact patients

Answer 39

single dose ciprofloxacin or rifampicin

Question 40

what are the preventative measures of bacterial meningitis ?

Answer 40

vaccination against strep pneumonia and N.meningitidis C and H.influenza

Question 41

how do we treat the complications of bacterial meningitis ?

Answer 41

for the dehydration ( IV fluids) give dexamethasone to decrease oedema give anticonvulsants

Question 42

what antibiotic to use with anaerobic bacteria ?

Answer 42

metradinazole

Question 43

what is the surgical treatment for brain abscess ?

Answer 43

stereotactic aspiration of the brain abscess , excision

Question 44

what to give for raised intracranial pressure ?

Answer 44

mannitol IV

Question 45

how to treat and manage a case of viral encephalitis?

Answer 45

control fever give antivirals - acyclovir for 2 weeks proper anti epileptic drugs

Question 46

treatment for fungal meningitis ?

Answer 46

symptomatic treatment

Question 47

what would confirm a diagnosis of Rabies ?

Answer 47

saliva testing , ab in CSF

Question 48

what is the treatment for rabies ?

Answer 48

human rabies vaccine

Question 49

locked jaw and gave birth recently ?

Answer 49

ask about tetanus shot (clostridium tetani)