04/09/2025
I have another heartwarming story to share with our followers and friends. This one I thought required a lot of detail in order to paint a picture of just how complicated some of the cases we see are.
A 10 year old spayed female Potcake presented to me in April of 2024. Her clinical signs were vague but concerning; intermittent, selective appetite and weight loss. A f***l floatation and smear showed the microscopic organism giardia. After the giardia treatment not much changed, her appetite still struggled, stool remained soft and she continued to lose weight. A diagnostic journey began to get to the bottom of the issue which included specialized blood tests, x-rays, ultrasounds, a f***l PCR and f***l culture. Pancreatitis was discovered which could explain the clinical signs but not necessarily the duration. Also, pancreatitis is often a secondary disease, meaning it happens because of some other disease process. We began managing the pancreatitis but again little changed. Discussions were had regarding surgical sampling of certain organs within the abdomen and we were preparing for surgery but then something changed…..Her total calcium was found to be extremely high on her pre-surgical blood work. This was a huge clue. More testing confirmed a diagnosis of hyperparathyroidism which is actually fairly uncommon in dogs. This disease can occur as a primary disease due to a tumor of the parathyroid gland or as a secondary disease due to other factors. We ruled out the other factors with history and blood work so a tumor was likely.
Calcium in the body is regulated by the parathyroid glands. There are four very tiny glands that are embedded within the thyroid glands – two parathyroid glands and one thyroid gland on each side of the trachea (windpipe). They are located about halfway down the neck. An increase in calcium concentrations in the blood occurs when the glands produce and secrete an excessive amount of parathyroid hormone (also named PTH). Primary hyperparathyroidism in dogs is most commonly caused by a functional benign adenoma or hyperplasia of one or more of the parathyroid glands, but can be caused by a malignant tumor (carcinoma).
Chronically elevated calcium can interfere with normal cellular and organ function leading to impaired kidney function, abnormal heart rhythms, decreased smooth muscle contractions in the digestive system, and generalized weakness due to its effect on the nervous system.
The treatment of this disease most often involves the surgical removal of the affected gland. Sounds easy right? It’s not; the parathyroid gland is normally about 3 mm in size and is embedded in the thyroid gland very close to not only the wind pipe, the carotid artery, the jugular vein and some very important nerves. Ideally a specialist is needed, as not only is the surgery delicate but post-operatively the dog’s calcium can plummet so quickly they can have serious complications including death. The reason for this is that the adenoma would have been producing so much calcium that the other 3 parathyroid glands would have responded by not producing any (called a negative feedback loop). With the removal of the overproducing adenoma it takes a while for the other glands to essentially wake up and start to function again. To prevent this post-surgical emergency, patients are started on calcium supplements and Calcitriol immediately after surgery and are then slowly weaned off them to ensure their calcium levels are being maintained properly.
Unfortunately, in this instance, the dog was unable to see a specialist. I reached out to many colleagues regarding the way forward. It was suggested to try a medication given to lower the amount of PTH being produced but this did not work; calcium levels remained high and appetite remained low. I continued to research and reach out to colleagues. After many conversations, weeks of research, some help from a few special colleagues, and the trust of the patient’s owner we devised a plan.
The tumor was first identified by ultrasound to determine its exact location (as there are 4 glands). The Calcitriol was acquired from a special compounding pharmacy in the USA. Once all steps had been planned and treatment protocols were in place we performed the tumor extraction. It was the first canine parathyroidectomy done to date in the Bahamas. The surgery went well and the patient recovered nicely. Over the next 4 months we slowly weaned her off of the calcium supplements and Calcitriol, periodically taking Calcium samples to make sure it was at the desired level. The tiny little tumor that wrecked such havoc was only 5 mm in diameter. It luckily was NOT a malignant carcinoma.
Today the patient is fully recovered, eating well and has gained her weight back. We are all thankful for the good outcome and all of the support from so many in making this happen.
Dr Greensword
