Case #216 – November, 2007

An asymptomatic, 35-year-old male with no known travel history went to his physician at a wellness clinic for a routine examination. An ova and parasite (O & P) examination was performed as part of the laboratory work-up at the State Health Laboratory. Unusual objects were observed in the formalin-concentrated stool, and the specimen was sent to CDC for diagnostic assistance and possible identification. Figures A-D were captured from wet mounts of the specimen. The objects measured approximately 50 micrometers by 42.5 micrometers. What is your diagnosis? Based on what criteria?

Figure A


Figure B


Figure C


Figure D

This case was kindly contributed by the Washington State Public Health Laboratories.

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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