Microbiology Lecture 4.22: Clostridium perfringens

Which is the most isolated clostridium species?

C. perfringes

Can C. perfringes be a harmless colonizer?

Yes

Can C. perfringes cause severe infection?

Yes

Are C. perfringes hemolytic?

Yes

What do C. perfringes form in blood agar?

Double zone of hemolysis

What are C. perfringes a normal part of in humans?

Intestinal Microbiota

Where are C. perfringes widely present in?

1. Soil

2. Water

3. Feces-contaminated environments

What is the virulence factor of C. perfringes?

Alpha Toxin (Phospholipase C)

What damage is caused by alpha toxins?

1. Tissue necrosis

2. Edema + Shock

3. Hemolysis

How do alpha toxins cause tissue necrosis?

Destroys cell membranes

How do alpha toxins cause edema + shock?

Increase vascular permeability

When do C. perfringes infections arise?

Bacteria enters tissues via wounds or surgery

What are the transmission methods of C. perfringes?

1. Simple wound contamination

2. Cellulitis

What is the diseases caused by C. perfringes?

Clostridial myonecrosis (Gas gangrene)

Why is Clostridial myonecrosis life threatening?

Abundant alpha toxin production

What is Clostridial myonecrosis characterized by?

1. Gas in tissues

2. Extensive muscle necrosis

What is gas build up in Clostridial myonecrosis caused by?

Metabolic activity of rapidly dividing bacteria