Canine Immune Mediated Disease
Sylvia Evans, September 2002
A small group of Afghan Hound
owners, including myself attended the CIMDA (Canine Immune Mediated Disease
Awareness which is a support group Beardie Collie Breeders/Owners founded
primarily by) Seminar at Coventry in June.
In view of the current health survey being carried out by the Breed Council, it
was disappointing that so few from the Afghan fraternity took this opportunity
to come along and listen to experts in their field speaking about autoimmune
disease and the genetic in-Put, Possibly those who have said to me in the past
that they have no personal knowledge of specific AI conditions in their dogs,
might have learned a little more about this very complex subject. Additionally a
rare Opportunity was missed, Jean Dodds over from the U.S.A., interrupting her
holiday in Venice, spoke so eloquently on her speciality, Canine HypoThyroid
Disease; Jean is internationally recognised as an expert in her field of
veterinary medicine, Auto-Immune Disease(s) Those of us who have heard her
presentations before were aware that we were in for a very interesting day. Sara
Gould, from Cambridge Vet School, another excellent speaker who talks to you as
an equal and is very practical in putting over a complex subject, gave us an
insight into some of the more commonly aware auto-immune disorders, age, the
risks, trigger factors, diagnosis, treatments and prognosis and of work
currently being undertaken at Cambridge. Information on the AI Disease survey
currently being undertaken at Cambridge, is included here in the following
article that Jo Tucker has given permission to be reproduced in this magazine,
please do assist if anyone reading this who has dog suffering from an
auto-immune disease and may not be aware of the survey. 1 have suggested to Bob
Margraine who is conducting the Breed Council Health Questionnaire, that owners
participating who likewise report experience with an AID in any of their dogs
(past and present), be asked if they would also consider participating in this
project.
Jeff Sampson's excellent presentation on the genetics of dog breeding and the
implications for the future, 1 felt personally was the best 1 have heard him
give, and 1 have heard Jeff speak on a number of occasions, including Afghan
2000 when 1 shared the platform with him in discussing Genetic/related Health
matters and the Afghan Hound.
Jeff suggested that whilst line breeding is recognised as a fundamental part of
pure bred breeding, specifically to maintain type, it can also present unwanted
side effects and the chance of producing recessive alleles which are involved in
perpetuating inherited disease patterns and in-breeding depression. Popular
sire(s) may dominate litter registrations, this must lead to a reduction in
genetic variation. Whilst one would not suggest that certain dogs should not
continually be used at stud, we as dog breeders should be a little more aware of
careful selection and alter-natives, such as like to like, where dogs are
similar but not closely related, to think about the dog rather than personal
ego. Honesty, open-mindness and encouragement for such with more thought to the
long term than in the immediate glories and achievement of the show ring.
All three speakers emphasised the role that owners and breeders might contribute
in trying to reduce the incidence of auto-immune diseases, now and in the future
with so many advances in technology, both for diagnosis, screening and testing.
All this made for a most interesting and informative day with audience
interaction. Jo Tucker who is the driving force behind CIMDA, had worked so hard
with her "team" to make this such a successful event, a packed house audience
with delegates from all Breeds, a few vets and several travelling from mainland
Europe, and as Jo said to me after, that even a seminar about a serious topic
can be a good day out and a sociable event.
I include here some of the subject matter for information
When dealing with AI disease we must consider the genetic predisposition; age,
gender: and environmental influences.
In many cases the actual cause of the illness is not identifiable but there may
be a pattern of events. those "Trigger Factors" that could influence the
outcome.
Certain auto-immune diseases have a high prevalence in certain breeds or in
"Family Lines".
Some pale/dilute/colour dogs appear susceptible to certain "triggers".
Many of these auto-immune diseases present in middle age (so these dogs may have
already contributed to a breeding programme).
Some are more common in bitches.
Environmental Factors noted from documented case histories .... That many cases
of auto-immune anaemia's occur in the summer months.
A definitive diagnosis is not always easy to reach but certain tests may prove
conclusive for treatments to be commenced.
Treatment is not curative. the aims of all treatment is Control of the disease
process and this be very successful.
In many conditions it does buy Time ... Quality Time .... for the affected dog
and this is very important. Treatments generally involve the use of a "cocktail”
specific drugs. Some dogs may be able to be weaned off their drugs but relapses
do occur and dogs are frequently maintained on various levels of medication
throughout their lives
Testing is Very Important, some tests may throw up false negatives so always be
prepared to have your vets repeat.
Test Bitches between heat cycles, viz 12 weeks from the onset of the season
(count from the first day of the season)
Diagnosis of Hypo-Thyroid Disease, in its early stages can be difficult to
detect on a clinical assessment but blood tests will indicate.
Those dogs even presenting negative should be re-tested every year if there are
plans to breed with them. Hypothyroid disease generally presents between 3 - 5
years of age but it is also being seen in younger dogs, (1 - 2 Years of age).
Tests for screening for thyroiditis do now exist.
Dogs with this disease can be affected for years before developing any
significant signs of illness indeed the diagnosis might be difficult at an early
stage even with some sick dogs, this is an auto-immune disease, it may not be
until the thyroid gland is the hormone produced. so necessary for the regulation
of body metabolism, is so depleted, which will progress to affect many other
vital organs, that the dog may show signs and more obvious symptoms….and some
that may be not so obvious to this disease process. Cardiac arrhythmia’s cardio-myopathy,
gastro-intestinal disorders, neurological conditions and behavioural changes,
especially aggression can all predispose thyroid disfunction. In studies in
America, results have indicated a significant existence in thyroid disfunction
and seizure related disorders and to some dog/human aggression presenting at
puberty.
Repetitive vaccination can be a "Trigger" to a number of AI diseases. Antibody
Titre Testing may prove a more valuable tool in determining your dog's
vaccination needs. Research has shown that once an animal's titre level
stabilises, it is more likely to remain constant for many years. Some owners of
dogs with auto-immune disease subscribe to the view that if you are suppressing
the immune system with the drugs to control the disease, the last thing that you
want to do is to stimulate the system by vaccination. There is far less risk
associated with taking blood samples for a titre test than giving the dog
unnecessary vaccination .... The protocol for vaccines is changing here in the
U.K. Intervet are about to announce their new recommendations (September 2002)
that Boosters should now be given every 2 years and not annually. In the U.S.A.,
all the vet colleges recommend re-vaccinating every 3 years.
A titre reading is a means of testing a blood sample taken from the dog for
circulating anti-bodies against specific diseases (viz CPV..Distemper:Hepatitis)
but it does not measure cell memory mediated immunity. Titre Testing is
relatively inexpensive (£24/26 Cambridge and Glasgow). When dealing with any
auto-immune disorder nothing is in black and white, there will always remain
grey areas.
From my own experiences, and from that relayed to me by others, I would always
advise that if you are in any doubts about the direction that is being
undertaken by your vet in dealing with any unresponding symptoms/illness, to
seek referral for a second opinion. It would seem that "Rat poisoning" or
exposure to some unknown chemical is frequently diagnosed for what could be
really one of the Bleeding auto-immune conditions, such as haemolytic anaemia or
thrombocytopenia (this is a platelet disease) or Von Willbrands Disease.
Many of these diseases are not common, but neither are they uncommon and they
are certainly not New! They have possibly been with us for years, we just know
more about them and are learning more with advances in both human and veterinary
medicine. 1 first learned about AI anaemia and thrombocytopenia as long ago as
1986 when I attended a Bristol Vet School Breeders weekend. In the research that
was being undertaken at this particular school 2 Afghan Hounds (both bitches)
were documented ... 1 wrote about the condition in one of the Southern magazines
around that time. Both Bristol and Cambridge are now seeing an increase in the
number of Afghan Hounds being referred to them with auto-immune disease.
My own Nureyev was diagnosed with Hypo-Thyroid disease in 1999 and remained well
and controlled on medication (Soloxine). With regular blood testing we were able
to monitor his thyroid function and review his medication as necessary,
generally it was an upward curve, -he medication frequently needed adjustments
but he remained a happy and active dog. Unfortunately he went on to develop the
polyglandular auto-immune syndrome *in the last few months of his life and
despite the best of veterinary care and advice from specialist experts in both
the U.K. and the U.S.A., when it became all too obvious that his quality of life
was fading it was kinder to say goodbye but we had 3 very good years and he was
by then 11 years old. In complete contrast my young dog Dance Master was only 3
years old when he became ill and whilst it was all to obvious that his immune
system was severely compromised we were never able to confirm a positive
diagnosis for a named condition "label" and this is something that is being seen
with a number of dogs in a variety of breeds, some may respond to drug therapy,
others go into a period of remission, others go down hill very rapidly, despite
the best of efforts and this is devastating for their owners.
There is a great "Pool of Information" available at this
time, from a variety of sources, much is practical information/help from owners
who have "Been There”…. We each need to share our experiences, although 1 know,
and at times can understand, why some may be reluctant to come forward and speak
about such matters ... but it does not help anyone in the long term when, as 1
have found, individual owners/breeders either go on the immediate defensive if
questions are raised about bloodlines or like minded individuals start damning
specifically named dogs or breeding lines and seem to gain some pleasure in
attempting to "Witch Hunt" or "Point Fingers" at those who are prepared to stand
and admit to a problem in their effort not to perpetuate it ... We must be
prepared to share our experiences, even the painful ones, in the short term it
offers a means of support to owners who suddenly find themselves coping with the
unknown. Even some members of the veterinary profession may not always recognise
or have the experience in dealing with some of these diseases and such are too
frequently mis-diagnosed. In the long term we will all be contributing to the
future well being of our breed's perpetuation and existence resulting in happy
and healthy dogs to be enjoyed as we have enjoyed them, for many more future
generations.
One final comment, it is no crime to have bred a dog that has developed a
significant health problem, these are living individual creatures, but it is a
crime to bury your head in the sand as if it had never happened and ignore the
issue.
Polyglandular Auto-Immunity
Individuals genetically susceptible to auto-immune thyroid disease may also
become more susceptible to immune mediated diseases affecting other target
tissues and organs, especially the bone marrow, liver adrenal gland, pancreas,
skin, kidney, joints, bowel and central nervous system. The resulting
polyglandular auto-immune syndrome of humans is becoming more commonly
recognised in the dog, and probably occurs in other species as well. This
syndrome tends to run in families and is believed to have an inherited basis.
Multiple endocrine glands and non-endocrine systems become involved in a
systemic immune mediated process ... in short the body system starts to destroy
itself, the auto-antibodies are destroying all vital functions.