Case #409 – December 2015

A 42-year-old dairy farmer sought medical attention for watery diarrhea, fever, and nausea that he had been experiencing for about one week. A stool specimen was collected for ova-and-parasite (O&P) work-up that included a formalin ethyl-acetate concentration. A fecal smear was prepared from the concentrate and stained with Kinyoun’s modified acid-fast stain. Figures AE show what was observed at 1000x magnification with oil in moderately high numbers on the acid-fast stained fecal smear. The stained objects measured 5 micrometers in diameter on average. What is your diagnosis? Based on what criteria? What, if any, other tests would you recommend?

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

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