Two weeks ago a paper was published in the Acta Veterinaria Scandinavica journal.  The first reported case of an Endometrioma in a dog.  A German Shepherd, to be precise.  Now don’t be too surprised; primates have been found to develope endometriosis: gorillas, monkeys, and baboons.  But this is the first time captured in literature that an animal has developed an Endometrioma.  What’s that?  A blood-filled cyst consistent with Endometriosis, sometimes referred to as a Chocolate Cyst.

The German Shepherd was 11 years old and was presented to a hospital in Brazil and had been suffering for the past month from dehydration, anemia, and prostration (laying down stretched out).  She had previously had “multiple natural deliveries,” had gone into heat routinely twice a year, and was never given any contraceptives.  During her precursory examination, she suddenly passed away.  An autopsy was performed and a mass was discovered on her left ovary.  Upon inspection and biopsy, it was confirmed to be an Endometrioma.  They theorize that animals, especially a dog, must develop Endometriosis through the coelemic theory, since they do not shed their endometrial lining or have retrograde menstruation.  She also did not have heightened levels of estrogen or hormones, which is another theory in Endo among humans.  What is the coelomic theory? I had to look it up, too :

The coelomic metaplasia theory. This theory proposes that the coelomic (abdominal) cavity contains cells capable of dedifferentiating into endometrial tissue. This theory is based upon embryologic studies demonstrating that all pelvic organs, including the endometrium, are derived from cells lining the coelomic cavity and these cells have the ability to become whatever they want to become. ~ Dailystrength.org

The poor old gal.  I know (and many of you know) how painful this can be.  Let’s hope she didn’t suffer, unable to express her pain and discomfort to her owners, forced to lay there in inexplicable discomfort, helpless.

Resources:

Acta Veterinaria Scandinavica – (Article; June 2015) – A rare case of endometrioma in a bitch