Bacterial Infections of CNS

Question 1

70% of all bacterial infections in 2000 were due to what 3 infections?

Answer 1

1. streptococcus pneumoniae
2. haemophilus influenzue
3. Neisseria meningitidis

Question 2

What are the two main types of bacterial meningitis

Answer 2

1. community acquired meningitis
2. nosocomial bacterial meningitis

Question 3

community acquired bacterial meningitis

Answer 3

acquired spontaneously from exposure to environment

Question 4

3 examples of community acquired bacterial meningitis

Answer 4

1. h. influenza
2. s. pneumonia
3. n. meningitidis
   aka the 3 most common bacterial infections

Question 5

nosocomial bacterial menigitis

Answer 5

acquired in the hospital or as a result of an invasive medical procedure

Question 6

3 examples of nosocomial bacterial menigitis

Answer 6

1. e. coli
2. other streptococcus spp
3. staphylococcus spp

Question 7

Epidemiology of bacterial infections

Answer 7

• has changed since introduction of vaccines
• highest burden is seen in africa
• the meningitis belt in africa

Question 8

what is the meningitis belt

Answer 8

• region of sub-saharan africa that experiences recurring outbreaks

Question 9

what are some factors that contribute to the recurring outbreaks seen in the meningitis belt

Answer 9

• weather related
• social/cultural influences
• health infrastructure

Question 10

7 common themes from community acquired bacterial infections

Answer 10

• extracellular organisms
• express virulence factors that allow them to survive in bloodstream <- prerequisite
• can target endothelia of the brain
  (most direct interactions)
• cross at areas that are considered leaky
• can be prevented through vacccinations
• similar groups are at risk

Question 11

Vaccines in the US

Answer 11

• no federal requirements, CDC can only make recommendations
• each state establishes vaccination requirements for school children
• this only applies to kids attending schools (public, private, and day care)

Question 12

Classic triad for meningitis

Answer 12

Headache/fever, malaise, and neck pain

Question 13

Listeria monocytogenes is normally contracted through

Answer 13

contaminated food

Question 14

Treponema pallidum is generally contracted how?

Answer 14

sexually transmitted

Question 15

Borrelia burgdorferi is generally contracted how

Answer 15

tick borne

Question 16

Burkholderia pseudomallei is generally contracted how?

Answer 16

tropical climate associated with water

Question 17

Commonalities of listeria monocytogenes, borrelia burgdorferi, and burkholderia pseudomallei

Answer 17

• these infections, in addition to meningitis, can also cause encephalitis and/or myelitis
• Occurrence should raise the suspicion of an immune deficiency or an unusual source of infection
• They are not normal commensals, must be acquired from external sources
• They all have specialized surfaces
• Can use multiple or unique ways to cross the CNS barriers
• L. monocytogenes can invade BMECs directly, then infect contiguous tissue, or use Trojan horse.
• The spirochetes use unique shape and motility to “drill” a hole between cellular barriers, including BBB
• B. pseudomallei can invade nerves peripherally and spread cell-to-cell back into the CNS.
• Big challenge, diagnosis!

Question 18

Myelitis

Answer 18

infection of the nerves and/or glia of the spinal cord that result in the inflammation of the spinal cord

Question 19

2 broad types of myelitis

Answer 19

acute and transverse

Question 20

Examples of most infectious diseases that cause myelitis

Answer 20

b. burgdorferi, s. aureus, b. pseudomallei, m. leprae, and most viruses

Question 21

most autoimmune diseases cause what type of myelitis

Answer 21

transverse myelitis

Question 22

example of viruses that can cause transverse myelitis

Answer 22

polio or herpes

Question 23

Transverse myelitis is mostly idiopathic because?

Answer 23

the cause is not known