Case #167 – November, 2005

A 45-year-old woman went to her physician with complaints of recurring abdominal cramping, bloating, and infrequent diarrhea. Her travel history included a 10-day camping trip in Alaska, and her symptoms had started approximately 2 weeks after her return. Her physician ordered an ova and parasites (O & P) examination. Figures A-D show objects observed on a trichrome stained fecal smear; A-C were found in moderate numbers on the smear, while D was found in very few numbers. The objects shown ranged in size from 5 to 7 micrometers. 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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