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Old 12-14-2013
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Bacteria Microbiology case - Gram negative rods

Hello guys,
Im new here and i need ur help I have to present a presentation in microbio on monday. We got this case and we had to find out which disease it is.
The topic is gram negative rods in enteric tract.

Case # 3.
Mr. D., a 33-year-old fully immunized, rather nervous accountant who is blood group O positive and taking H2 blockers for ulcer disease, his 29-year-old healthy wife and their 10-month-old baby boy returned from a 2-week trip to South America. The next morning Mr. D. passed a semisolid stool, which was quickly followed by a large watery bowel movement. Within an hour he passed another large watery stool, now opaque gray–white in color. He vomited several times and became slightly sweaty. After passing another large watery stool, Mr. D. called his physician, who advised him to go to the emergency department. When he arrived there Mr. D. was afebrile but had a rapid heart rate with a feeble pulse and low blood pressure. He complained of muscle cramps and dizziness. All these signs and symptoms were consistent with a significant loss of extracellular fluids. Laboratory studies showed a normal
leukocyte count, a slightly elevated level of serum sodium, a normal serum potassium level, and an elevated blood urea nitrogen level, also consistent with dehydration. A diagnosis of cholera was suspected. Mr. D. was immediately given 2 liters of fluid intravenously and then started on oral rehydration solution. His stool volumes progressively diminished over 48 hours, and he was discharged. Mrs. D., a native Peruvian, had two loose bowel movements on the second day of her husband's illness. Her stool culture grew only Escherichia coli.

1. Classify the pathogenic E. coli and representative serotypes. What are
the symptoms of diseases they may develop? What is the epidemiology?

2. What is the most likely organism causing Mr. D’s disease?

3. Are all enteric bacteria capable of causing disease, or are some more frequently pathogenic than others? Which enteric pathogens cause diarrhea and where do they come from?

4. What are the clinical manifestations caused by the diagnosed pathogen?

5. Why did Mrs. D. not show the same symptoms?

6. What factors are involved in colonization? What factors are involved in causing symptoms?

7. What is the proper therapy for this disease?

So this is the whole case. I`m unsure between cholera cause by vibrio cholera or travelers diarrhea cause by enterotoxigenic E.coli. The first question is confusing me -.-

hope u have any ideas
thank you in advance
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Old 12-14-2013
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pls can someone help me. i need to do the presentation on monday.

I DONT need the answers for the questions, i Just want to know if its Cholera or travelers diarrhea.

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