Clostridium perfringens
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Bacteria - Gram Positive
- Staph aureus: Overview
- Staph aureus: Presentation
- Methicillin-Resistant Staph aureus (MRSA)
- Staph saprophyticus
- Strep pneumoniae: Overview
- Strep pneumoniae: Presentation
- Strep viridans
- Strep pyogenes: Overview
- Strep pyogenes: Presentation
- Strep agalactiae
- Strep bovis
- Enterococcus
- Bacillus anthracis
- Bacillus cereus
- Clostridium tetani
- Clostridium perfringens
- Clostridium botulinum
- Clostridium difficile
- Corynebacterium diphtheriae
- Listeria monocytogenes
- Nocardia
- Actinomyces
Clostridium perfringens
- Characteristics
- Common to all bacteria in Clostridia family
- Gram + rods
- Obligate anaerobic
- Spore-forming
- Spores live in soil
- Double zone of beta-hemolysis on blood agar
- Produces lecithinase (an exotoxin)
- Also known as phospholipase C or alpha-toxin
- Cleaves membrane lipid lecithins (phospholipase) to cause cell lysis (e.g. hemolysis), tissue necrosis, and edema
- increases platelet aggregation and adherence molecule expression on WBCs and endothelial cells, resulting in blood vessel occlusion and ischemia in downstream tissues
- Exposure
- Penetrating injury
- Spores enter via contaminated objects (e.g. soil, surgery)
- Penetrating injury
- Presentation
- myonecrosis (gas gangrene)
- Rapid developing necrotizing fasciitis in skin and soft tissue, mediated by lecithinase
- Tissue damage and necrosis with gas that can be felt on examination (crepitus)
- Purple-black discoloration of affected limb
- Late-onset food poisoning
- Caused by ingestion of large amounts of spores producing heat-labile enterotoxin
- Transient watery diarrhea occurs in 10-12 hours after ingestion
- Occurs slowly since toxin is not pre-formed
- Hemolysis
- myonecrosis (gas gangrene)
- Treatment
- Immediate surgical debridement for gas gangrene
- Surgical emergency, poor prognosis even with treatment
- Antibiotics
- Penicillin and clindamycin
- Immediate surgical debridement for gas gangrene