CNS Infections

Question 1

Myelitis

Answer 1

inflammation of the spinal cord

Question 2

meningitis

Answer 2

inflammation of the meninges

Question 3

How much time one has to send the CSF for analysis?

Answer 3

1 hr

Question 4

WHat is the most common cause of meningitis?

Answer 4

Viral

Question 5

Aseptic Meningitis means there is no pathogenic cause T/F

Answer 5

F, just that nothing grew on culture. could be due to viruses or the patient being given Antibiotics

Question 6

Main cause of bacterial meningitis in children and adults?

Answer 6

Neisseria meningitides (AUs B-C, World A)
Streptococcus pneumonia
Haemophylus influenza B (<5yo)

Question 7

Main cause of bacterial meningitis in neonates?

Answer 7

Neisseria meningitides (AUs B-C, World A)
Streptococcus pneumonia
Haemophylus influenza B 
E coli
Neisseria monocytogenes
Group B streptococci

Question 8

Main symptoms and signs of meningitis?

Answer 8

stiff neck
photophobia
fever
vomiting 
headache

Question 9

What does bacterial sources of meningitis in adults share in common?

Answer 9

Capsulated and can inhabit nose

Question 10

What is the gold standard for the diagnosis of bacterial meningitis?

Answer 10

grow bacteria from the CSF: Culture, Gram Stain, PCR

Question 11

Is symptoms of meningitis are present but CSF is normal what is the diagnosis?

Answer 11

Suspected Meningitis

Question 12

if patient has meningococcal meningitis what must have he had beforehand?

Answer 12

meningococcaemia (purpuric rash: non blanching)

Question 13

Characteristics of CSF

Answer 13

Glucose 60% of blood
protein <5x10^6 u/l
Blood -

Question 14

Characteristics of viral meningitis

Answer 14

high glucose
low protein
100s lymphocytes

Question 15

Characteristics of bacterial meningitis

Answer 15

1000s lymphocytes
low glucose
high protein
gram +

Question 16

Treatment of meningitis

Answer 16

1 Resuscitation/life support
2 fluids
3 antibiotics
4 contact prophylaxis

Question 17

What causes the symptoms in bacterial meningitis?

Answer 17

the immune response

Question 18

What is the antibiotic treatment for bacterial meningitis?

Answer 18

3Rd gen cephalosporins
If neonates
+ penicillin and gentomycin

Question 19

Define encephalitis

Answer 19

inflammation of the brain parenchyma mainly due to viral infection

Question 20

Most common cause of viral encephalitis

Answer 20

Herpes Simplex Virus

Question 21

Neurotropism
Neuroinvasiveness
Neurovirulence

Answer 21

1 replicates in nerve cells
2 enters and infects the CNS
3 capable of causing disease within nervous system

Question 22

Most common pathogen in meningitis

Answer 22

Enteroviruses

Question 23

What is one of the most serious viral diseases? cause

Answer 23

Viral encephalitis, herpes simplex virus and rabies virus

Question 24

What is post-infectious encephalitis?

Answer 24

inflammation and demyelination of the brain without any pathogen present (measles, chickenpox, rubella, mumps)

Question 25

Guillan Barre syndrome?

Answer 25

acute inflammatory demyelinating disease following viral infection (EBV, cytomegalovirus and HIV) causes debilitating paralysis

Question 26

Reye's Syndrome

Answer 26

Cerebral oedema w/out inflammation post infection of influenza or chickenpox in children (25% mortality rate) related with aspirin use for fever

Question 27

Viruses that are obligated neurotropics?

Answer 27

Herpes simplex virus and Rabies virus

Question 28

What virus can only reach the brain by blood infection?

Answer 28

polio

Question 29

What is the form of the genome for herpes virus?

Answer 29

linear dsDNA

Question 30

herpes virus has low ----1-- but high ---2---

Answer 30

neuroinvasiveness | neurovirulence

Question 31

What is the most common cause of severe sporadic encephalitis?

Answer 31

herpes simplex virus

Question 32

is herpes simplex virus enveloped?

Answer 32

yes, icosahedral

Question 33

Neuronal route is the most common way of infecting the brain by HSV?

Answer 33

true, rarely by blood

Question 34

What is the main way varicella zooster might reach the brain?

Answer 34

by blood after replication in the airway mucosa

Question 35

when does the rash appears in varicella zooster infection?

Answer 35

in the secondary viraemia after replicating in the spleen and the liver

Question 36

latent reactivation of varicella zooster virus shows as

Answer 36

Shingles

Question 37

Which viral infection produces LATs and ehat are they?

Answer 37

Latency Activated mRNA, because the DNA remains in the ganglia as episomes Herpes Simplex virus

Question 38

WHat type of genome does rabies virus has? is it enveloped?

Answer 38

-RNA and yes | helical

Question 39

Rabies is both very ---1--- and ----2----

Answer 39

neuroinvasive and neurovirulent

Question 40

where does rabies replicates before reaching the nerves?

Answer 40

muscle tissue at place of bite

Question 41

Rabies virus is perfect in hiding from the inmmune system T/F

Answer 41

F, its replication causes glycoproteins to show in the host cells membrane

Question 42

What part of the rabies virus is transported by the nerves?

Answer 42

nucleocapside

Question 43

Nerves show MCH 1

Answer 43

No they do not

Question 44

WHat is the characteristics of polio virus?

Answer 44

+RNA no envelope icosahedral capsule belongs to enterovirus

Question 45

polio virus has low ----1-- but high ---2----

Answer 45

Neuroinvasiveness | neurovirulence

Question 46

polio virus is neurotropic

Answer 46

False

Question 47

what is one of the complications of polio virus infection?

Answer 47

acute IRREVERSIBLE flaccid paralysis (<1%)

Question 48

why does poliovirus causes acute IRREVERSIBLE flaccid paralysis

Answer 48

because it is able to kill the cells of the ventral horn of the spine (also able to cross bbb)