Ch.22: Microbial Disease of The Nervous System

Question 1

What is Bacterial Meningitis

Answer 1

infection of the membrane surrounding the brain & spinal cord; cross the blood-brain barrier

Question 2

What is Neisseria meningitides (meningococcal meningitis) caused by

Answer 2

caused by meningitides; gram-negative, aerobic diplococci with a capsule

Question 3

What are the virulence factors of Neisseria meningitis?

Answer 3

-Opa protein (entry into cell)
-Endotoxin; capsule; pili
-phase variation

Question 4

What is the diagnosis of meningococcal meningitis?

Answer 4

-begins as a throat infection, rash leads to bacteremia–> crosses the blood-brain barrier into the cerebrospinal fluid

Question 5

What is listeriosis

Answer 5

foodborne illness, characterized by flu-like, and GI symptoms

Question 6

What is listeria monocytogenes

Answer 6

-small, Gram-positive rods
-Widely distributed in soil/water
-in mammals, birds, fish, insects
-grow at low temps

Question 7

What is Clostridium species?

Answer 7

-Anaerobe grows in canned food releasing toxins; spores survive unless autoclaved
-Toxins interferes with neural transmission by blocking release of acetylcholine
-causes flaccid paralysis

Question 7

What is C. botulinum?

Answer 7

Botulism toxin (“Botox”)

Question 8

What is Clostridium Tetani

Answer 8

• C. tetani: tetanus toxin (tetanospasmin
• Anaerobe, grows in picture wound; blood flow interrupted; tissue becomes anaerobic

Question 9

What do tetanus toxin blocks

Answer 9

the release of GABA, inhibitory transmitter

Question 10

What does tetanus toxin cause

Answer 10

nerve impulses to go unchecked; spastic paralysis via excessive nerve signaling

Question 11

What are obligately anaerobic Gram-positive bacilli & endospore formers?

Answer 11

Clostridium tetani & clostridium botulinum

Question 12

What are the modes of action of tetanospasmin, and botulism toxin?

Answer 12

-Have 30-40% identity, and similar modes of action. Each are a A-B type toxins.

Question 13

What is rabies caused by

Answer 13

rabies virus (ss RNA); transmitted by animal bite; typically leads to fatal encephalitis.

Question 14

Steps of rabies virus infection

Answer 14

1.) Virus enters tissue from saliva of biting animal
2.) Virus replicates in muscle near bite and enters neuron of peripheral nervous system
3.) Virus moves up peripheral nervous system CNS
4.) Virus ascends spinal cord
5.) Virus reaches brain and causes fatal encephalitis
6.) virus enters salivary glands and other organs of victim

Question 15

What are the initial symptoms of rabies?

Answer 15

muscle spasms of the mouth and pharynx and hydrophobia

Question 16

How does the rabies virus multiply?

Answer 16

In skeletal muscle and then brain cells, causing encephalitis

Question 17

What is furious rabies?

Answer 17

animals are restless, then highly excitable

Question 18

What is paralytic rabies?

Answer 18

animals seem unaware of surroundings

Question 19

What are Negri bodies

Answer 19

viral inclusions present in affected nerve cells

Question 20

What is a zoonotic disease?

Answer 20

infections that are spread between people and animals