Microbiology case study! Help please!

dratelectasis · April 12, 2013

The patient was a 3-year old female referred to the pediatric clinic with a 5 week history of diarrhea. It was characterized as green and often watery. Although potty trained, she was occasionally incontinent of feces. She had no fever, nausea or vomiting. She was an only child who attended group day care and her mother had diarrhea for 3 days about 1 month previously. The family drank filtered water. Her physical examination was unremarkable. Upon stool examination, a typical unicellular protozoan parasite was seen under direct fluorescent microscopy.

1) what kind of parasites can cause such diarrhea?

2) Are there virulence factors of this pathogen?

3) This organism is of particular concern in children day care settings. Why?

4) Why can this organism cause outbreaks of infection that can affect thousands of individuals.

5) How are these infections typically diagnosed?

***Please note that I have my gut instinct on the amoeba species but it may be cryptosporidiosis or giardia. Any concrete ideas? I need to present the case by Monday. I don't need the answers to 2-5. I just need to know what the species is. Thank you very much in advance

And please, if you don't know the answer, don't reply.

Edited April 12, 2013 by dratelectasis

pwagen · April 12, 2013

And please, if you don't know the answer, don't reply.

Not really up to you who gets to reply on a public forum, now is it?

Parasites that cause diarrhea include Giardia lamblia, Entamoeba histolytica, and Cryptosporidium.

http://digestive.niddk.nih.gov/ddiseases/pubs/diarrhea/

Looking at those, it appears two of those can result in both bloody diarrhea and vomiting, which leaves the third one with symptoms that match, making it slightly more likely.

http://en.wikipedia.org/wiki/Giardia_lamblia#Manifestation_of_infection

http://en.wikipedia.org/wiki/Entamoeba_histolytica#Transmission

http://en.wikipedia.org/wiki/Cryptosporidium#General_characteristics

Edited April 12, 2013 by pwagen