Case #363 – January 2014

A 49-year-old female passed a worm-like object approximately three weeks after attending a Thanksgiving potluck for 200 people. Prior to the Thanksgiving meal, the patient had experienced diarrhea for two weeks. The worm was presented to a local hospital. Follow-up stool ova-and-parasite (O&P) examinations were negative. The Microbiology Department took digital images (Figures AC) of the worm and sent them to the DPDx Team for diagnostic assistance. The initial finding from the images was reported simply as ‘cestode’ and the specimen was forwarded to the DPDx Team for further study. Upon arrival, the specimen was placed in lactophenol for clearing. Figures D and E show what was observed in the proglottids after clearing for two days. The objects measured 60 micrometers in length on average. What is your diagnosis? Based on what criteria?

Figure A

Figure B

Figure C

Figure D

Figure E

This case and images (in part) were kindly provided by the Evanston Hospital Microbiology Department, Evanston, IL.

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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