Module 4 -> Anaerobes & Clostridium

Anaerobes & Clostridium

Anaerobic Bacteria

Bacteria that live without oxygen; obligate anaerobes cannot tolerate oxygen.

Obligate Anaerobe

A bacterium that cannot tolerate oxygen.

Anaerobic Infections

Often mixed infections involving abscesses, wounds, pneumonia, abdominal infections, bacteremia, or enteric disease.

Anaerobic Antibiotic Rule

Aminoglycosides do not work against anaerobic bacteria.

Clostridium

A group of important anaerobic bacteria that includes several toxin-producing species.

Clostridium tetani

The bacterium that causes tetanus.

Tetanus

A disease caused by Clostridium tetani toxin that causes spastic paralysis.

Tetanospasmin

The neurotoxin produced by Clostridium tetani.

Tetanus Mechanism

Tetanospasmin blocks inhibitory neurotransmitters GABA and glycine.

Tetanus Paralysis

Spastic paralysis.

Tetanus Treatment

Antitoxin, wound debridement, and antimicrobials to stop further toxin production.

Tetanus Prevention

Vaccination.

Clostridium botulinum

The bacterium that causes botulism.

Botulism

A disease caused by botulinum toxin that causes flaccid paralysis.

Botulinum Toxin

A neurotoxin that prevents release of acetylcholine.

Botulism Paralysis

Flaccid paralysis.

Botulism Treatment

Antitoxin can neutralize unbound toxin.

C. chauvoei

A histotoxic Clostridium associated with severe muscle infections.

C. septicum

A histotoxic Clostridium associated with severe tissue infections.

C. novyi

A histotoxic Clostridium associated with severe tissue infections.

C. perfringens

A Clostridium that can cause enteritis, enterotoxemia, and tissue infections.

Histotoxic Clostridium

Clostridium species that cause severe tissue infections such as myositis and gas gangrene.

Clostridium perfringens Type C

Causes necrotizing enteritis in piglets.

Clostridium perfringens Type D

Causes pulpy kidney disease/overeating disease in sheep and goats.

Pulpy Kidney Disease

Another name for enterotoxemia caused by C. perfringens Type D.

Clostridium difficile

An organism that can overgrow after antibiotics disrupt normal intestinal bacteria.

Dysbiosis

Disruption of the normal microbial population.

C. difficile Disease

Can cause severe or fatal colitis after disruption of normal flora.

C. difficile Horse Warning

Clindamycin is contraindicated in horses according to the notes.

C. spiroforme

Causes enterotoxemia and explosive diarrhea in young rabbits.

C. spiroforme Rabbit Warning

Lincomycin, clindamycin, and erythromycin are contraindicated in rabbits.

Clostridium piliforme

The bacterium that causes Tyzzer's disease.

Tyzzer's Disease

An acute, potentially fatal disease causing diarrhea and focal liver necrosis.

C. piliforme Special Fact

C. piliforme is a Gram-negative exception and cannot be cultured in the laboratory.

Fusobacterium necrophorum

A Gram-negative anaerobe associated with liver abscesses and mixed infections.

Dichelobacter nodosus

A Gram-negative anaerobe associated with foot rot.

Foot Rot

A disease associated with Dichelobacter nodosus in cattle and sheep.