Case #488 – March, 2019

Fecal specimens were collected from a refugee population as part of a screening program. Specimens were collected fresh for a direct smear examination and in polyvinyl alcohol (PVA) from which smears were prepared and stained with trichrome stain. Figures AD show what was detected in one of the specimens using 1000x oil magnification; objects of interest measured 14-20 micrometers on average. Figure D is of the same objects at two different focal planes. What is your diagnosis? Based on what criteria?

parasitic image

Figure A

parasitic image

Figure B

parasitic image

Figure C

parasitic image

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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Page last reviewed: April 18, 2019