Bacteria I Gram (+)

Question 1

Genus Clostridium Shape

Answer 1

Bacilli (rod shaped)

Question 2

Primary Pathogenic Members of the Genus Clostridium

Answer 2

C. botulinum: Botulism

C. difficile: Gastro-enteritis

C. perfringens: Gastro-enteritis, Gas Gangrene

C. tetani: Tetanus (Lockjaw or Trismus)

Question 3

Tetanus Transmission

Answer 3

1. Endospores in environment
2. Endospores enter through deep cut
3. Endospores only germinate if circulation is poor (e.g., anaerobic environment)
4. Vegetative cells produce tetanospasmin

Question 4

Clostridium toxins

Answer 4

Tetanospasmin:

• From C. tetani
• Aka tetanus toxin (TeTx) or spasmogenic toxin
• Blocks GABA and glycine (inhibitory NT)  unrestrained muscle activity

Botulinum Toxin (BT):

• From C. botulinum
• Aka botulin or botox
• Blocks acetylcholine release (excitatory NT)  flaccid muscle paralysis

Question 5

Tetanus Symptoms

Answer 5

Due to toxins
Spastic paralysis (no muscle relaxation)
Profuse sweating
Opisthotonos (every muscle is contracting-position)
Risus sardonicus (Grin) 
Tachycardia
Patient is fully alert

Question 6

Tetanus Treatment

Answer 6

Clean wound

TIG: tetanus immune globulin (passive vaccine)

TAT: tetanus antitoxin (from horses: serum sickness)

Muscle relaxants

Assisted breathing (respirator, tracheostomy)

Antibiotics (penicillin, tetracycline)

Question 7

Tetanus Prevention & Control

Answer 7

Toxoid vaccine (the “T” in DTaP)

Booster injections at time of wounding

Public education

Question 8

Botulism Transmission

Answer 8

1. Endospores accidentally incorporated into commercial or home canning containers
2. Bottling/steaming insufficient to kill endospores
3. Endospores germinate in can; toxin produced
4. Human ingests toxin-laden food

Question 9

Botulism Symptoms

Answer 9

Due to toxins

Headache
Double-Vision
Slurred Speech
Progressive Flaccid Paralysis
Eventual respiratory failure

Patient is fully alert

Question 10

Botulism Treatment

Answer 10

Antitoxin (HBAT—heptavalent botulism antitoxin):
Only for certain subtypes
From horse: serum sickness

Respiratory problems may persist for months or years

Sometimes permanent neurological damage

Question 11

Botulism Prevention & Control

Answer 11

Don’t eat food from bulging or hissing cans

Inactivate the toxin: boil 10 minutes

Inactivate/kill the bacterium:
Boiling is insufficient
Need heat AND pressure (e.g., pressure cooker)

Can food in acidic conditions: (create an environment that the bacteria does not like)
Salt
Sodium nitrite
Vinegar

Question 12

Gas Gangrene Transmission

Answer 12

1. Puncture
2. Endospores germinate in wound
3. Toxins produced
4. Patient has infection + intoxication

Question 13

Gas Gangrene Symptoms

Answer 13

Anaerobic Cellulitis:

• Local
• Toxins/gases produced
• “Snap, crackle, pop” (tissue die-off)

Necrotizing Fasciitis:

• Moves systemic
• Painful
• Necrotic; invariably fatal if untreated

Question 14

Gas Gangrene Treatment

Answer 14

Treatment:
Debridement or amputation
Antibiotics specific to the strain
Hyperbaric oxygen chambers

Question 15

Gas Gangrene Prevention & Control

Answer 15

Sore/wound hygiene

Question 16

C. Difficle Transmission

Answer 16

Normal Gut Flora

1. C. difficile is in gut at low numbers
2. Broad-spectrum antibiotics destroy other flora AND/OR Anti-acid medications favor survival, growth
3. C. Difficile populations swell
4. Infection + intoxication

Question 17

C. Difficile Symptoms

Answer 17

Diarrhea

Advanced cases:

• Cramping
• Fever
• “Pseudomembranes” of bacteria and intestinal wall evacuated
• Death if colon ruptures

Question 18

C. Difficile Treatment

Answer 18

• Withdraw broad-spectrum antibiotics, acid suppressors
• Treat with narrow-spectrum antibiotics
• Fecal microbiota transplantation

Question 19

C. Difficile Prevention and Control

Answer 19

Prevent spread from infected individuals, especially nosocomially