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Posted by

Date
May 2, 2010
4:31 pm

Tagged

Category
Microbiology

Answer to Case of the Week 50

Answer: As stated by cmassey, “Toxoplasma gondii. Criteria: rupturing cyst with what appear to be escaping tachyzoites. Morphology is crescent shape with a large nucleus and they appear to fit in the 4-8um by 2-3um size given in diagnostic literature.”

Great job to everyone who wrote in! This case demonstrates a few nice features of T. gondii. First, there are both cyst and free tachyzoite forms as seen here:

Also, many of the tachyzoites demonstrate the classic ‘arc’ shape (Toxon is Greek for arc):

2 Comments

Posted by
Chris

Date
May 2, 2010 @ 7pm

what was the history behind the biopsy?

Posted by
Parasite gal

Date
May 3, 2010 @ 10pm

To answer Chris’s question, the patient was immunocompromised with end-stage AIDS. That’s the only history I have.
thanks for writing in!
Bobbi

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