II-A. Systemic Bacteriology | 21. Clostridium tetani and Clostridium botulinum

Question 1

I. Clostridium tetani
1. What are the features of Clostridium tetani?

Answer 1

• terminal endospore formation
• peritrichous fimbriae
• beta-haemolysis on blood agar
• swarming!

Question 2

I. Clostridium tetani
2. What is the source of infection of Clostridium tetani?

Answer 2

usually from the environment (soil)

Question 3

I. Clostridium tetani
3. What is the route of transmission of Clostridium tetani?

Answer 3

direct inoculation (through injury)

Question 4

I. Clostridium tetani
4A. What is the disease caused by Clostridium tetani?

Answer 4

tetanus

Question 5

I. Clostridium tetani
4B. What are the features of tetanus?

Answer 5

1. spastic paresis of skeletal muscles
   - Trismus (lockjaw)
   - sardininan grin
   - opisthotonus
   - asphyxia! (resp. muscle paresis)
2. incubation time depends on the distance of infection site from the spinal cord

Question 6

I. Clostridium tetani
5. How do we diagnose diseases caused by Clostridium tetani?

Answer 6

• based on clinical sign and symptoms
• usually sampling is not performed (wound swab)
• laboratory: culturing (anaerobic)

Question 7

I. Clostridium tetani
6A. What is the therapy for diseases caused by Clostridium tetani?

Answer 7

• terminal endospore formation
• peritrichous fimbriae
• beta-haemolysis on blood agar
• swarming!

Question 8

I. Clostridium tetani
6B. What is the therapy before the appearance of symptoms (tetanus prone and high risk wounds)?

Answer 8

• wound care
• post-exposure immunization (booster tetanus-vaccine)
• wound care (necrectomy, lavage)

Question 9

I. Clostridium tetani
6C. What is the therapy for symptomatic disease?

Answer 9

• wound care
• intravenous TETIG (human anti-tetanus toxin immunoglobulin)
• antibiotics (penicillins, metronidazol)
• muscle relaxant, artificial ventilation

Question 10

I. Clostridium tetani
7. What is the prevention for diseases caused by Clostridium tetani?

Answer 10

DTPa mandatory vaccine

Question 11

II. Clostridium botulinum
1. What are the features of Clostridium botulinum?

Answer 11

• found in GI microbiota of different animals
• central or subterminal endospore formation
• intensive gas production

Question 12

II. Clostridium botulinum
8. What is the patho-mechanism of botulism?

Answer 12

Question 13

II. Clostridium botulinum
3. What are the virulence factors of Clostridium botulinum?

Answer 13

exotoxin A-E

Question 14

II. Clostridium botulinum
4. How does Clostridium botulinum infect

Answer 14

• usually only intoxication (technically food poisoning)
  +) in infants might be a real bowel infection
• wound infection might happen rarely

Question 15

II. Clostridium botulinum
5A. What is the source of infection of Clostridium botulinum?

Answer 15

Question 16

II. Clostridium botulinum
5B. Why is “contaminated food consumption (ingestion of preformed toxin)” the source of infection of Clostridium botulinum?

Answer 16

canned / fermented food
* anaerobic environment
* spores survive cooking, proliferate, produces toxin
* bacteria usually die over time, but the toxin is quite stable

Question 17

II. Clostridium botulinum
6. What are the diseases caused by Clostridium botulinum

Answer 17

botulism

Question 18

II. Clostridium botulinum
7. What are the feature of botulism?

Answer 18

• flaccid paresis (toxins inhibits ACh release of motoneurons)
• incubation period: few hours – 2 days
• spores are found in honey naturally!

Question 19

II. Clostridium botulinum
9. What is the effect of botulism to baby?

Answer 19

spores are found in honey naturally!
* as infants do not have a developed GI microbiota, they could be colonized
* bacterium produces toxin in the bowels (“infection”)
* “floppy baby syndrome”

Question 20

II. Clostridium botulinum
10. How do we diagnose Clostridium botulinum

Answer 20

• based on clinical signs and symptoms
• sampling: food, blood, stool
• laboratory: toxin detection (injecting animals; rarely)

Question 21

II. Clostridium botulinum
11. What is the therapy for Clostridium botulinum?

Answer 21

• IV antitoxin: trivalent human serum (anti-A, anti-B, anti-E antitoxin)
• antibiotics are not needed!