Case #454 – October, 2017

An eleven-year-old male from Arizona with no known past medical history was evaluated in the ophthalmology clinic after a 3-4 week history of progressive redness in his left eye, with associated pain and growth of a nodule. There was no record of travel outside the US. However, the patient went on a trip with his school on the Colorado River. An excisional biopsy of the left eye conjunctiva revealed objects consistent with a parasitic worm infection. Figures AE show what was found in the hematoxylin & eosin (H&E) stain of the biopsy. What is your diagnosis? Based on what morphologic features?

This case was kindly contributed by the Arizona State Health Department

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Figure A

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Figure B

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Figure C

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Figure D

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Figure E

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: December 11, 2017