Patho Micro Exam 2- Clostridium tetani

Clostridium tetani resembles a what in appearance?

drumsticks because of their round terminal spores

Is Clostridium tetani motile?

yes

Is Clostridium tetani a spore-former or not?

spore-former

Clostridium tetani spores are found where?

widespread in soil

How does Clostridium tetani typically enter the body?

Through a wound

Germination of C. tetani spores is favored by what?

necrotic tissue and poor blood supply

C. tetani is extremely sensitive to what?

oxygen

C. tetani causes what the disease?

tetanus "lockjaw"

What two toxins are produced by C. tetani?

tetanolysin and tetanospasmin

What type of toxin is tetanolysin?

hemolytic (type II)

What type of toxin is Tetanospasmin?

heat-labile neurotoxin (A-B)

What is tetanospasmin encoded by?

plasmid-encoded

What is the primary virulence factor for C. tetani?

Tetanospasmin

Where is tetanospasmin produced?

the wound site by vegetative cells

How is the tetanospasmin toxin taken up?

receptor-mediated endocytosis

Where does the tetanospasmin toxin go?

CNS

Once at the CNS, what happens?

the light chain goes to the cytosol

What does the tetanospasmin light chain do?

inactivate proteins that regulate the release of inhibitory neurotransmitters glycine and GABA

Because regulatory proteins have been deactivated, what happens?

spastic paralysis

If someone has tetanus, where will they have spasm?

In their back and their masseter muscles

Risus sardonicus

spasm of the masseter muscles that causes a characteristic grimace

Opisthotonos

arched back from spasms

What are symptoms of tetanus?

drooling, sweating, and irritability

Aside from spasms, what are other signs of tetanus?

cardiac arrythmias and respiratory failure

What is neonatal tetanus a result of?

Infection of the umbilical stump

Recovery of function for those who had tetanus requires what?

regeneration of nerve endings

What antibiotic absolutely cannot be given to those who have tetanus?

Penicillin

Why can't those infected with tetanus take penicillin?

it inhibits GABA activity, so spasms would only become more severe

What antibiotic is given to those with tetanus?

metronidazole

Passive immunization can be given to those infected with tetanus using what?

human tetanus immunoglobulin

What is in the tetanus vaccination?

tetanus toxoid