Case #452 - September, 2017

A man, with no reported travel outside of Canada and who was immunocompetent, had complaints of abdominal cramping and diarrhea that had been ongoing for more than two weeks. A stool specimen was collected for ova-and-parasite (O & P) examination which included a formalin-ethyl acetate concentration (FEA) and subsequent iron hematoxylin –modified acid-fast combination stain. Figure A shows what was detected on a wet mount prep and Figures B and C on the combination stained fecal smear. Objects of interest measured 25-30 micrometers on average. What is your diagnosis? Based on what criteria?

This case and images was kindly provided by the Cadham Provincial Public Health Laboratory, Winnipeg, MB

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Figure A

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Figure B

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Figure C

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.

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Page last reviewed: December 12, 2017