Hyperparathyroidism: How this Tumor Increased One Dachshund's Thirst

Dr. Phil Zeltzman is a traveling, board-certified surgeon in Allentown, PA. His website is www.DrPhilZeltzman.com. He is the co-author of “Walk a Hound, Lose a Pound” (www.amazon.com).

AJ Debiasse, a veterinary technician in Stroudsburg, PA, contributed to this article.

Senior male dachshund

Sprout, a 14-year-old male Dachshund was constantly drinking and urinating. His guardians thought that he just needed to go out more because he was getting older, but despite the increase in potty breaks, Sprout was still having accidents in the house. It was time for a visit to his veterinarian.

A full physical exam was performed. Nothing abnormal was found. No masses or enlarged lymph nodes were palpated and all of his vital signs were normal. The veterinarian recommended blood work to evaluate Sprout’s body functions.

What did blood work reveal?
The only abnormality was an elevated calcium level (hypercalcemia). Since hypercalcemia can be a sign of multiple conditions, radiographs and an ultrasound were performed. The radiographs were unremarkable, but the ultrasound showed a small mass on the right parathyroid gland.

The parathyroid is a gland located next to the thyroid. In fact, there are 2 thyroid glands and 4 parathyroid glands (2 on each side). The parathyroid glands are mainly responsible for regulating calcium levels in the blood. When one gland it hyperactive, it produces too much parathyroid hormone, which increases the calcium levels. This condition is called “hyper-para-thyroidism.” In addition, when one gland is hyperactive, the 3 other glands become lazy and don’t produce much parathyroid hormone.

What causes hyperparathyroidism?
The cause is not known. It can happen in any dog breed, usually between 5 and 15 years of age. One canine breed is particularly susceptible: the Keeshond—in which the disease is partially genetic.

What are the symptoms of hyperparathyroidism?
The symptoms vary and include increased drinking and urination as in our friend Sprout. Other signs include:

  • A decreased appetite
  • Vomiting
  • A decreased activity level
  • Weakness

Because of the increased calcium level, kidney or bladder stones made of calcium can occur. It is therefore critical to look for the presence of stones with X-rays or ultrasound.

If you have any questions or concerns, you should always visit or call your veterinarian -- they are your best resource to ensure the health and well-being of your pets.

Treating hyperparathyroidism
Ultrasound has made a huge difference in the way we approach these tumors. At one time, we had to look around, poke around and mess around. Now, through a completely non-invasive test, we know exactly where the mass is, and which side it’s on. This means less trauma for the patient, and a much quicker surgery, which translates into a shorter anesthesia.

To treat Sprout’s hyperparathyroidism, surgery was required to remove the tumor. The mass was exactly where the ultrasonographer had said it would be and removed safely. Our patient stayed in the hospital overnight for recovery. By the next day, the calcium level was significantly lower. By the second day, the calcium was normal. While we waited for the 3 remaining parathyroid glands to “wake up” and start making parathyroid hormone, Sprout received calcium supplements and vitamin D. The dosage of both supplements was slowly decreased over time.

The calcium level was checked a few more times over the next week, and it remained normal. Sprout went home with antibiotics and pain medications. His activity was restricted for 2 weeks, and the skin sutures were removed 14 days after surgery.

The biopsy report was also reassuring: the mass was a benign tumor (parathyroid adenoma). Sprout is now back to his normal self and his guardians couldn't be happier.

As with any other disease, if your pet’s behavior changes in any way, do not assume it's normal or old age. More often than not, there is an underlying condition that can be corrected, so please contact your veterinarian as soon as possible.

Questions you can ask your vet

  • Why is my pet drinking and urinating more than usual?
  • Why is my pet having vomiting or diarrhea?
  • Why has my pet’s appetite increased or decreased?