August, 2008

Case 233
A 37-year-old man began experiencing severe diarrhea about one week after attending a family social event.  At the request of his medical provider, a fecal specimen collected in the two-vial system consisting of one vial with 10% formalin and one vial with Zn-PVA (zinc-based polyvinyl alcohol) was submitted for examination.  An FEA concentration procedure and wet mount examination was done on the formalin preserved specimen.  Figures A-C shows structures that were found in moderate numbers at 1000x magnification.  The structures measured about 8-10 micrometers in diameter.  A smear was made from the specimen preserved with PVA and stained using trichrome.  Figures D and E show similar round objects that were observed.  What is your diagnosis?  Based on what criteria?  What other testing methods would you suggest?

A	B

 

C	D

 

E

Click here for the answer to Case 233.

Case 234
A 29 year-old man with travel history to Costa Rica, Belize, and Nicaragua developed an ulcerative lesion on his right foot.  The lesion did not respond to over-the-counter medications so the patient went to his health care provider.  He was referred to an infectious disease specialist due to his travel history.  A biopsy was performed near the edge of the lesion and the tissue specimen was sent to a reference laboratory for testing.  The tissue specimen was divided into two parts, one of which was used to inoculate a NNN slant for culture.  The other part was used to prepare a touch-prep smear, which in turn was fixed with methanol and then stained with Giemsa.  Figures A and B show what was observed on that smear.  What is your diagnosis?  Based on what criteria?

A	B

Click here for the answer to Case 234.

Images presented in the monthly case studies are from specimens submitted for diagnosis or archiving.  On rare occasions, clinical histories given may be partly fictitious.