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15 Cards in this Set
- Front
- Back
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what disease do Shigella cause
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Bacillary dysentery, severe cramping, abdominal pain, and diarrhea with blood and mucous
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PAthogenesis mode of activity in Shigella
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Invasion of mucosal cells in distal Ileum and colon
As few as 200 organisms are able to cause disease |
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Gram/morphology of Shigella
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Gram negative rods
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TSI results of Shigella
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K slant, A butt
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H2S production in Shigella
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Negative
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Growth pattern on MacConkey
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no lactse fermentation, colorless colonies
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motility of Shigella
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non
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Gas from glucose feremntation (Shigella)
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No
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Virulence factors of Shigella
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O antigens divided into A,B,C,D
Heat labile Shiga neurotoxin (produced by S. dysenteriae |
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What is the mode of avtivity for Shiga neurotoxin
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A subunit - inhibits protein synthesis, alters ability to transport electrolytes, neurotoxic acitivty (convulsions-coma)
5 B subunits - binds toxin to suscpetible cells |
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How is Shigellosis spread
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person to person, with asymptomatic carriers
day cares, hospitals, ccruise ships |
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Prevention and control of shigellosis
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isolate and treat active cases
hygiene, sewage disposal, chlorinated H2O |
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Good tests to differentiate S. sonnei from other Shigella
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OPNG +
Ornithine Dec + INdole - |
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Good tests to differentiate S. dysenteriae from other Shigella
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Mannitol -
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Good tests to differentiate S. flexneri
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Raffinose Delayed
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