That "P" Word . . . by Kris Arnds

Catchy title? Got your attention? I've thought about this article for a while, and although I didn't want to write it. I finally decided I needed to write it. So what is the "P" word? Parathyroid. No, not the thyroid—we can all test our dogs for that and certify the results. The parathyroids are tiny glands near the thyroid gland. Among other things, they are responsible for secreting a hormone that regulates the calcium/phosphorous ratio in the dog. Unfortunately, it is becoming ever more apparent that our beloved breed is at risk for Primary Hyperparathyroidism (PHPT). This occurs when a small, usually benign tumor grows on one or more of the four glands, causing it/them to malfunction and secrete too much parathyroid hormone into the bloodstream. This, in turn, causes the calcium level in the blood to rise as calcium is sucked out of the bones, eventually leading to the atrophy of the other parathyroid glands and severe damage to the kidneys and other organs. Undetected, this insidious disease wreaks havoc on the dog and it eventually dies of what seems to be "old age"—but "old age" arrives prematurely, sometimes as early as 8-9 years old.

Having dealt with this disease in one of my dogs, I have learned a great deal about it and feel I should pass on what I now know to others, hopefully saving some dogs along the way. I have chosen a question/answer format, trying to anticipate the questions other Kees owners might have.

1. Is this a disease confined just to our breed?
No, it occurs in all breeds and in mixed breeds. However, according to the UCDavis Book of Dogs (a layman's medical reference book), "PHPT occurs in older dogs (average age, 10 years). Keeshonds, German Shepherd Dogs and Norwegian Elkhounds appear to have a predisposition for this disorder. . ."(p.315). The surgeon who took care of my dog told me of the last 12 cases seen at her hospital, two were Keeshonden and at least one was a mixed breed.

2. Is this a disease of certain bloodlines?
No. Keeshonden are widely known to be at the top of the list for this disease, and this indicates it is in many dogs in the breed, and not just in well-known lines. In fact, in the recent KCA Health Survey, this problem was reported by owners and breeders to be one of the top four known health conditions. This survey covered dogs from breeders across the country , as well as dogs bred in puppymills and by backyard breeders.

3. Can breeding stock be tested for this?
No. At this time, there is only a test to confirm the tumor, but that does not usually occur until well past a dog's breeding years. This means that an affected dog can produce a large number of puppies before anything is suspected. Dr. Gary Johnson, at the Univ. of MO., has said that a genetic screening test is possible but will take a research project to produce. Such a test could allow us to screen all our breeding stock prior to putting them in a breeding program, as well as alert us to which of our dogs are at risk for developing the disease. Presumably, this screening could be done at a very early age.

4.What are the signs of PHPT?
PHPT can manifest itself in many ways. The primary symptom is hypercalcemia, or an increase in blood calcium. Currently the normal range for adults is considered to be 8.9-11.4. A blood calcium above this is a warning sign. If this is the case, a second blood test for Parathyroid Hormone (PTH) can be taken. The ONLY lab in the U.S. that currently runs this test is at Michigan State Univ. It takes about 10 days to get the results, which are usually conclusive.
Another sign of PHPT is loose teeth and brittle bones, both due to calcium loss from bones. When these signs are present, the disease is probably well-advanced and there is probably irreversible kidney damage.

5. Sounds glum. Can anything be done, or is this always fatal?
While PHPT is a very serious disease, it is NOT a death sentence! All Keeshonden should be given an annual exam, including a blood panel after age 7 or 8. This will establish the normal calcium level for the dog. If the calcium rises above the normal range, suspect a problem and investigate it--the sooner the better! My dog showed a calcium of 12.1 on one test and 12.5 on another. I immediately took her to an oncologist who had done a number of these surgeries and began the necessary steps to confirm the diagnosis.

6.What does the surgery entail?
The surgeon described the surgery as rather straightforward. It is "non-invasive," in that it does not invade any organs or body cavities. The incision is in the neck, below the chin, The surgeon checks each parathyroid gland for the tumor and removes any affected gland. If the disease is not well-advanced, the remaining glands are not atrophied and they will take over and continue to regulate the calcium. However, if the calcium level is 14 or above, the probability that the other glands have atrophied is dramatically increased and the recovery is more difficult.

7. What about after surgery care?
There have been a number of dogs that have had the surgery, only to die soon after. The problem here seems to be a lack of knowledge regarding aftercare. My dog was a good candidate for the surgery, as her blood calcium was 12.5 and her PHPT test, ironically, was "inconclusive." It seems we had caught the disease before the tests could confirm it!! After surgery, she was kept hospitalized for two days while the staff monitored her calcium level. In the first test post-surgery, the level had dropped from 12.5 to 10.4. At that point I was allowed to take her home, but not before being given specific instructions on what to look for to identify a calcium drop. I was also given two vials of calcium to keep on hand and instructed that if a crisis should occur, I was to take the vials of calcium with me to the emergency hospital, along with her records to show what had been done to her. Not all clinics have calcium on hand, and that was why I was given some to take.

Leaving the hospital was NOT the end of the care! I took her home on Wed., and I was immediately given appointments to have her calcium rechecked on Thursday and Saturday, and warned that if the Thursday test warranted it, she would also be tested on Friday. If necessary, she would be given a calcium supplement (Tums or calcium tablets). As her calcium leveled off, we continued monitoring twice weekly, then once weekly, then every other week, etc. I was also told about another Kees that was operated on last February, did quite well, and now comes in to be checked every three months. If my dog's calcium level is normal on her next visit, she will be discharged as "cured."

Of the two dogs I have heard of that did not survive post-surgery, both had calcium levels well above 14 prior to surgery, and both experienced severe calcium drops after surgery. In one case, the dog was released after only one day, obviously not yet stable, and almost immediately went into a crisis which lasted several days and ended in his death. The other did better, but succumbed after several months to calcium-related seizures after her low calcium level was misdiagnosed. She had had a previous back injury, and when she exhibited stiffness in her gait and soreness in her back—both indicative of low calcium--she was treated with cortisone for the perceived flare-up of the back condition. It would seem that vets are becoming more aware of this condition, but are not yet knowledgeable about post-surgery care/monitoring.

8. Will we ever be able to stamp out parathyroidism?
Only if we can support research to develop a genetic screening test. Of course, this will not mean dogs bred by backyard breeders or puppymills will be tested, but at least the owners of those dogs will have a test to alert them to the possible condition in their pets and allow them to seek treatment.

So there it is--almost everything I know about hyperparathyroidism—which is more than most people know, I suspect. I have a strong belief that this is in no way new to our breed; rather, I suspect it has been around for many years and probably affects many other breeds as well. Since obtaining my first Keeshond in 1970, I have known of many dogs—some from different "lines" and some from dubious pedigrees—that died of "kidney failure." Why do some kidneys fail at 8, some at 10, while others fail at 16? I suspect a number of these may have been affected by PHPT. The good news is that there is help for our affected pets now, and if we work together and avoid the pitfall of kennel blindness ("not in MY line!"), we can help to develop a test for PHPT that will save countless dogs in the future.

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