The Problem
As with all pure bred dogs, American Staffordshire terriers exhibit some health problems
that are most likely the result of genetic defects. Recently, the Staffordshire Terrier
Club of America's health committee has noticed that there are increasing numbers of dogs
developing a drunken, staggering gait and balance problems as they get older. This is a
particularly serious disease, as dogs do not exhibit signs until well into adulthood,
after they have been bred. Current research indicates that this is most likely a genetic
disorder.The Symptoms
This disease affects a particular part of the brain called the cerebellum. The cerebellum
is closely associated with the vestibular system and together these parts of the brain
control coordination of movements. There are many different diseases that can affect these
areas of the brain and therefore produce similar signs. Infection of the middle ear,
trauma, viral infections, tumors, autoimmune disorders and bacterial disease can also
cause vestibular and cerebellar signs. However, the order and rate in which signs develop
in dogs with this particular syndrome are characteristic of the disease. Both male and
female dogs are affected and signs may start from 2 - 5 years of age.
Initially, the signs are very subtle and include clumsiness and an
occasional sway of the body when making sudden movements. Agility dogs, for example, may
develop problems with a particular obstacle that they could previously negotiate without
difficulty. Dogs may trip and fall when negotiating steps or moving quickly. As the
disease progresses, the clumsiness becomes more pronounced: dogs may fall over when they
shake their head and often have an obvious body sway when they move their head quickly.
Male dogs may lose their balance while lifting their legs to urinate. When moving in a
controlled fashion in a straight line they may still look normal, but when turning
corners, chasing balls, and rushing for their food, the mistakes become obvious.
If the dog's eyes are watched carefully, it is noticed that sudden
movements of the head cause rapid flicking of the eyes (nystagmus), either from side to
side, round in circles or vertically. Rolling the dog onto its back is the most reliable
way of eliciting these eye movements and they usually last from a few seconds to about one
minute.
Other early signs of the disease may include sudden episodes of
collapse, with stiffening of all 4 legs, the neck and the body that last for a few
seconds. With time, the dogs have more and more difficulty walking because of lack of
coordination of their legs rather than weakness. The AmStaf may also lose weight as the
dog has balance difficulties reaching his food bowl.
Please remember that we are very early in our data collection
process. The age of onset, symptoms, and progression varies from dog to dog. The above
descriptions are general signs of hereditary ataxia. Your dog does not have to have every
characteristic listed in order to be considered affected. The one similarity that all the
dogs have shared thus far has been balance problems.
The Prognosis
The progression of the disease varies from dog to dog. For many AmStafs, the signs develop
slowly. The STCA health committee considers hereditary ataxia a "deadly" disease
since most AmStafs cannot live out a normal lifespan and must be humanely euthanized. Most
are not able to function past the age of 7 or 8. One note: if anesthesia is performed for
some reason (e.g. a routine dental), it may accelerate deterioration. We have witnessed
dogs with minimal signs waking up from anesthesia extremely unbalanced with obvious
nystagmus. These signs improve somewhat in the days after anesthesia, but the dog does not
recover to the level it was at prior to anesthesia.
The Diagnosis
If you have an AmStaf exhibiting any neurologic signs, (even those considered to be the
result of an ear infection or vascular event like a "stroke") it is HIGHLY
recommended that you seek the advice of a veterinary neurologist. If you need assistance
or advice, please contact Dr. Natasha Olby and her research team at the below numbers. A
complete neurologic workup is most helpful in ruling out the many other types of disease
processes that can produce the same symptoms. Tests that may include a complete blood cell
count, a biochemistry panel, a computed tomography (CT) scan or magnetic resonance imaging
(MRI) to evaluate the brain and middle ears for evidence of a mass (such as a brain tumor)
or infection in the middle ears, and cerebrospinal fluid analysis (spinal tap) to rule out
encephalitis. In dogs with this syndrome, all test results are normal. Post mortem
examination by a pathologist is one of the most helpful diagnostic tools we have. Data
gathering is critical to halting the spread of this terrible disease.
The Research
Dr. Natasha Olby has evaluated several of these dogs at North Carolina State University
veterinary teaching hospital and she is working to identify the genetic defect causing
this problem. Our aim is to develop a test for the disease to identify affected dogs prior
to breeding them. Similar syndromes occur in people and the genetic defects that cause
many of them have been identified. We are therefore starting our research by looking for
the same genetic defects described in humans.
We are interested in information from dogs who are currently exhibiting the problem as
well as dogs thought to have died from this disorder (or a similarly progressive
neurologic disease). For those of you who have had dogs die some time ago, your
information is still very valuable to us. If you suspect that your dog has this problem,
please contact Dr. Olby's research team by telephone: 919-513-6327 (ask to speak to Jeanne
Burr) or by e mail (jeanne_burr@ncsu.edu). They will need a description of your dog's
signs, with a videotape if at all possible. They will be able to tell you where the
nearest veterinary neurologist is located if they feel that your dog would benefit from a
full diagnostic work-up. If Dr. Olby suspects that your dog has this disease, we would
appreciate your help in solving the problem. All information is strictly confidential and
will be maintained by Dr. Olby and her team. No one else (including the health committee)
will have access to raw data. We are trying to determine how this disease is inherited and
the researchers may ask you for a copy of your dog's pedigree: this information will be
kept completely confidential at the vet school. Blood samples may also be requested from
your vet and would enable Dr. Olby to perform genetic analysis. These will be kept solely
for the purposes of this research project.
Investigator: Natasha Olby Vet. M.B., Ph.D., Diplomate ACVIM
(Neurology)
Research Assistant: Jeanne Burr 919-513-6327
If you would like to help but you do not have an affected dog, you
can contribute directly to the cause via donations. Checks can be sent directly to the AKC
Canine Foundation, 251 W. Garfield Rd. Suite 160, Aurora, Ohio 44202-8856. Please include
on the memo portion of the check "American Staffordshire Terrier Donor Advised
Fund". Donations are tax deductible and can only be used in health research for the
AmStaf. Please do not contribute directly to the health committee.
The Recommendations
Evidence indicates that this disease is on the rise, and that it may be present in Europe
as well. We are working with our counterparts there to gather more information. Until
genetic testing is available, we can only make recommendations for breeders to avoid
spreading this disease. Because ataxia is a late onset disease, do not breed young stock.
Do not breed ANY dog with neurologic symptoms (this includes those thought to be caused by
ear infections and strokes) unless it has been definitively diagnosed to have a
non-hereditary disease process by a neurologist. If you suspect a problem with your dog,
please participate in our research project. It is completely confidential, and it is the
only way we can battle this terrible problem.
Copyright © 2002 Staffordshire Terrier Club of America (STCA) All
rights reserved.
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