Term
| Name the two gram(+) spore-forming rods |
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Definition
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Term
| How do bacillus and clostridium metabolize oxygen? |
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Definition
Bacillus: aerobic
Clostridium: anaerobic (closet) |
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Term
| What are the two pathogenic species of gram (+), aerobic, spore-forming rods? |
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Definition
Bacillus anthracis --> anthrax
Bacillus cereus --> gastroenterits (food poisoning) |
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Term
| What is unique about Bacillus anthracis? |
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Definition
| B. anthracis has a capsule composed of protein (poly-D-glutamic acid)--which prevents phagocytosis |
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Term
| pathophysiology of anthrax |
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Definition
| stable B. anthracis spore germinates and makes toxins inside the human body |
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Term
| Where do we contract anthrax? |
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Definition
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Term
| Where is the deadly anthrax exotoxins encoded? |
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Definition
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Term
| 3 proteins of anthrax exotoxin? |
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Definition
* Edema Factor --> Increased cAMP --> Impaired PMN function, massive edema
* Protective Antigen: promotes entry of EF into phagocytic cells
* Lethal Factor: inactivate protein kinase, stimulate macrophage to release TNF-alpha and interleukin-1beta (---> death) |
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Term
| What is encoded in the plasmid pXO2 in Bacillus anthracis? |
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Definition
| three genes necessary for synthesis of poly-glutamyl capsule of the bacteria |
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Term
| How is Bacillus cereus different from Bacillus anthracis? |
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Definition
| B. cereus is motile, non-encapsulated, and resistant to penicillin |
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Term
| What are two types of enterotoxins secreted by Bacillus cereus? |
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Definition
* heat-labile toxin: nausea, abdominal pain, diarrhea; 12 - 24 hrs; similar to that of cholera and E. coli
* heat-stable toxin: short incubation period followed by severe nausea and vomiting, with limited diarrhea; similar to Staph. aureus food poisoning |
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Term
| T/F: treat Bacillus cereus food-poisoning with antibiotics right away |
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Definition
| F: gastroenteritis caused by pre-formed spores (not bacteria themselves) |
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Term
| What is the gram(+), spore-forming, ANaerobic rod? |
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Definition
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Term
| What does Clostridium botulinum result? |
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Definition
| Botulism. Lethal neurotoxin causes fatal food poisoning, blocks the release of ACh from presynaptic cell in the ANS and motor endplates (causing flaccid muscle paralysis) |
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Term
| Adult botulism: source, symptoms, treatment? |
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Definition
* NEUROTOXIN in the canfood
* afebrile, double vision, dysphagia, muscle weakness, sudden respiratory paralysis
* antitoxin (equine, horse-drived) |
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Term
| Infant botulism: source, symptoms, treatment? |
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Definition
* Clostridium botulinum SPORES in honey
* floppy, dysphagia, muscle weakness
* human botulism immunoglobulin intravenous |
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Term
| How is wound botulism different from adult botulism? |
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Definition
| no prodromal gastrointestinal symptoms, longer incubation period, more likely to have a fever, elevated WBC count |
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Term
| What does Clostridium tetani cause? |
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Definition
| Tetanus: follows a puncture wound by a rusty nail or any other trauma by an object infected with spores |
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Term
| How does tetanus toxin (tetanospasmin) cause tetany? |
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Definition
| the toxin prevents the release of GABA/glycine in the inhibitory interneurons in the CNS |
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Term
| How often do you have to get tetanus booster shot? |
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Definition
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Term
| What are "trismus" and "risus sardonicus"? |
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Definition
trismus: lockjaw, severe muscle spasms in the jaw
* risus sardonicus: grotesque grinning expression from spasm of facial muscles |
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Term
| what is tetanus vaccine made of? |
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Definition
| formalin-inactivated toxin |
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Term
| What causes gas gangrene? |
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Definition
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Term
| What are 3 classes of infection by Clostridium perfringens? |
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Definition
* cellulitis/wound infection: with crepitus (gas pockets)
* clostridial myonecrosis: gas pockets in the muscles and subcutaneous tissue; treat with hyperbaric O2, antibiotics, removal of necrosis tissue
* diarrheal illness |
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Term
| What does clostridium difficile cause? |
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Definition
| Pseudomembranous Enterocolitis. Antibiotics --> wipe out normal flora --> C. difficile dominates --> toxin A: diarrhea, toxin B: cytotoxic. fever and abdominal cramping |
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Term
| Treating Clostridium difficile |
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Definition
* Vancomycin (oral, not IV)
* metronidazole: either oral or IV |
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