Case #395 May 2015

Stool specimens were collected from an asymptomatic 12-year-old boy from Myanmar as part of a refugee screening program. The stool was collected in 10% formalin and zinc PVA (Zn-PVA) and sent to the county health department for routine ova-and-parasite (O&P) examination. Figures AD show what was observed at 1000x magnification with oil on a trichrome-stained slide made from stool preserved in Zn-PVA. The objects shown in Figures AC measured 12-15 µm in length, on average; the object in Figure D measured 7 µm. What is your diagnosis? Based on what criteria?

Figure A

Figure B

Figure C

Figure D

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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