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drpkaur
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08/13/06 - 11:18 AM

.A 57 year old man is brought to the Emergency Department by his family. He has a high fever (104OF) and blood pressure of 60/0 (normal for this man is 130/70). Blood cultures reveal the presence of lactose positive bacteria on MacConkey agar plates. Which of the following is most likely responsible for this man’s illness?

A.Heat stroke
B.LPS made by Escherichia coli
C.Double stranded RNA from a virus
D.Peptidoglycan made by Staphylococcus aureus
E.Myocardial infarct

vallia
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08/13/06 - 12:54 PM

B

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unique1
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08/13/06 - 02:34 PM

B . Ecoli is lactose +ve on MacConkey agar.

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Dragonfly
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08/16/06 - 06:59 AM

B.

Lactose (+) --> E.K.E. = E.coli, Klebsiella, Enterobacter

Slow Lactose Frementors --> Slov --> Serratia , vibrio

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drpkaur
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08/16/06 - 08:39 AM

good B is correct

which bacteria this is. Lac+ on MacConkey is from E. coli, not Staph. Answers A, C, and E aren’t related to anything you learned about at this point, and if someone has a bacteria in the blood along with shock symptoms you should think about it being a septic shock. E. coli has LPS and is the most common cause of G- sepsis (lipid A component of LPS)

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