Clostridium-Bacillus (EXAM III) Flashcards
Describe the gram stain & shape of Clostridium bacteria:
Gram positive; rods
A major virulence factor of Clostridium is that:
Endospore forming
Describe the oxygen requirement of Clostridium & spores:
Obligate anaerobes; spores are O2 resistant
Where can Clostridium be encountered:
Environment (soil) & intestinal mucous
How can we detect spores of Clostridium:
Endospores stain hot malachite green
Endospore staining is also used for:
Aerobic endospore formers like Gram + bacillus
Describe the virulence factors of Clostridium:
Spore formation
The spores of clostridium contribute to virulence because:
- Resistant to destruction
- Resistant to sterilization
- Resistant to antibiotics
How might we remove clostridium spores from a medical device?
Autoclave (Heat under pressure)
Boiling is NOT effective
When the disease-causing components is solely due to the toxin, this is referred to as:
Intoxication
The type of Clostridium that gives rise to severe form of food poisoning leading to paralysis if untreated:
Clostridium Bolulinum
In addition to food ingestion, Clostridium Botulinum may cause Botulism by:
Soil or fecal contamination
_______ is possible form soil or fecal contamination
Wound botulism
Explain how infant botulism occurs:
Because of lack of full development of normal intestinal flora, if Clostridium Botulinum is introduced to infant between weeks 30 & 20 it has the capability of rapid overgrowth
Describe the effects of infant botulism:
Muscle weakness; rarely paralysis
How does infant botulism resolve?
Normally resolves as intestinal flora develops
Describe the virulence factors of Clostridium Botulinum:
Botulinum neurotoxin (A-B exotoxin) blocks acetylcholine release
What does botulinum neurotoxin (A-B exotoxin) block & what does this cause?
Blocks Acetylcholine release; causes flaccid paralysis - can lead to death
Because Clostridium botulinum does not ______ it acts through _____
Invade tissues; toxins
The spores of clostridium botulinum are _____, while the botulinum toxin is _____
Heat-stable; heat-labile
How long does anti-toxin neutralization to the botulism toxin take to be effective?
Weeks to months
The form of Clostridium that is typically caused by dirty, puncture wounds (knife, bullet, tattoo) that are typically opportunities for the anaerobic growth of this pathogen:
Clostridium tetani
Describe the oxygen requirements of Clostridium Tetani:
Anaerobic
Bacterial growth of Clostridium Tetani remains _____ but the tetanus toxin _____
Localized; spreads
What toxin is responsible for the virulence of Clostridium Tetani?
Tetanospasmin
Describe Tetanospasmin:
Tetanus A-B exotoxin/neurotoxin; plasmid encoded
Describe the mechanism of action of tetanospasmin:
Blocks GABA & Glycine; leads to loss of inhibitory input to motor neuron excitation leading to spastic paralysis
In Clostridium tetani, the spastic paralysis is due to:
Uncontrolled muscle contraction caused by Tetanospasmin
The effects of Tetanospasmin may be:
Localized & one-sided (on opposite side of infection)
Describe the effects of anti-toxin against tetanospasmin:
Usually too late for anti-toxin treatment
Clostridium Tetani does not _____ so it acts through _____
Invade tissues; toxins
A dramatically deadly disease characterized by the in ability of muscle relaxation:
Tetanus
Tetanus toxin prevents:
Muscle relaxation
Infection with tetanus systemically can cause:
- Cardiac arrythmias
- Blood pressure swings
- Dehydration