Case #149 – February, 2005

A live worm was recovered from a 3-year-old’s diaper. The child was healthy and had not traveled outside of the country. The worm was preserved in 10% formaldehyde and forwarded to the Swedish Institute for Infectious Disease Control (SMI) for examination. The worm’s size was reportedly 6 cm long when first discovered, although when fixed, it measured 3.5 cm in length and 0.6 cm in width. Also due to fixation, the worm was brittle and had almost broke in half; no eggs or other structures came out of the broken area. At the tip of the thickest end, there was a crater-like opening with no apparent lips or teeth. Lab personnel at SMI captured images of the worm under a dissecting microscope and submitted a composite image, Figure A, to DPDx telediagnosis assistance. What is your diagnosis? Based on what criteria?

Figure A

Figure A

This case was kindly contributed by the Swedish Institute for Infectious Disease Control.

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: August 24, 2016