Case #183 – July, 2006

A family visited different U.S. states during a one week vacation. Approximately eight days after their trip, two family members began experiencing diarrhea. They went to their family physician and reported that while they were traveling they swam in hotel pools and at a waterpark. The physician requested stool samples for an ova and parasite (O & P) examination, along with other testing. The samples collected for the O & P were preserved in 10% formalin and then sent for examination. Figure A shows rounded objects seen on a modified acid-fast stained slide made from a formalin-ethyl acetate (FEA) concentrate of one of the specimens. The same objects were seen in specimens from the other family member who was ill. The objects measured 4.5-5.5 micrometers in diameter. What is your diagnosis? Based on what criteria?

Figure A

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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