August 2013

Ocular nematode?

 A one-year-old spayed female black lab was adopted from a shelter/rescue in Tulsa, Okla., 6 months previously.  The dog was current on all vaccinations and tested negative for heartworm antigen at the time of adoption.  The owner presented the dog because she was pawing at her eye.  The dog was not current on heartworm prevention at the time of examination. Mild sedation and close inspection exposed the source of irritation.

​Surgical removal and microscopic examination revealed...
​
Excision of the worm from the conjunctival sac revealed it was a female approximately 11.4 cm in length.

These larvae were found upon microscopic examination of the uterus.

What is your diagnosis?

Answer

These are first-stage larvae of Dracunculus insignis.  The long-thin tails of the larvae are distinctive. Normally found in subcutaneous connective tissue of limbs, D. insignis females can occasionally be found in the conjunctiva, heart, vertebral column, and scrotum.