Fentanyl Overdose after Cystic Ovarian Tumor Removal Surgery in a Hermaphrodite Green Anaconda (Eunectes murinus)
A 27-yr-old female green anaconda (Eunectes murinus) presented with coelomic distention in the posterior half of its body. On examination with imaging diagnostics, a fluid-filled cavity that seemed to be related to reproductive tissue was discovered. Diagnostics of this fluid confirmed cystic fluid, and a fine-needle aspirate of the mass determined that it was ovarian tissue. Ovariectomy and mass removal surgery was performed. During surgery, there was discovery of an additional unrecognized organ near the reproductive tract. Histopathology revealed an ovarian cystic neoplasm consistent with a granulosa cell tumor, and biopsy of the unknown structure was identified as a testis. Postoperatively, the green anaconda was administered fentanyl transdermal patches for analgesia and developed a severe adverse reaction, which improved after administration of the opioid reversal agent naltrexone. This is the first report of hermaphroditism in a snake as well as suspected negative side effects of transdermal fentanyl in a snake.Abstract
Photograph of the extruded cystic ovarian tumor and testis of a green anaconda (Eunectes murinus) taken intraoperatively. The ovarian tumor is denoted with a black triangle, and the rounded swelling surrounding it demonstrates the fluid-filled, encapsulated cyst associated with this neoplasm. The testis presented as an unexpected semifirm mass caudodorsal to the ovary and cyst, denoted here with a black asterisk. It was within its own sac, near to but unrelated to the female reproductive tract.
Microscopic images of the degenerative testis of the green anaconda (Eunectes murinus). The biopsy consisted of multiple cystic tubules filled with elongate structures suspected to be spermatids (asterisk), consistent with seminiferous tubules and testis. Tubules were found within congested fibrovascular connective tissue, with epithelial cells on the periphery and scattered heterophils. No tissue of adrenal or ovarian origin was noted. H&E stain; × 40 magnification. Courtesy of IDEXX Veterinary Diagnostic Services.
