Study in Akitas: inherited low platelet disorder (macrothrombocytopenia)

edited May 2013 in Akita (秋田犬)
Drs Sayuri Hayakawa DVM and Mary K Boudreaux DVM at Auburn University are doing a study on macrothrombocytopenia (inherited low platelet disease) in Akitas. This type of thrombocytopenia does not affect a dog's health and does not respond to treatment with steroids or antibiotics and should not be treated. They hope to prevent the unnecessary treatment of Akitas with inherited thrombocytopenia. Some Akitas treated for macrothrombocytopenia as if they had immune-mediated thrombocytopenia have become very ill or died.

They write:
We are trying to identify the gene mutation that causes macrothrombocytopenia in Akitas. So far, we have noticed that macrothrombocytopenia can occur in both American Akitas and Japanese Akitas (living in Japan and America). Unfortunately, there is no written literature on macrothrombocytopenia in Akitas even in Japan, and we hope that will change with our studies. This type of thrombocytopenia in Akitas does not respond to treatment with steroids or antibiotics. Currently, we are looking at various candidate genes that may be responsible for the cause of macrothrombocytopenia. When we evaluated Akita DNA, we did not see the mutation in the gene encoding beta 1-tubulin that causes macrothrombocytopenia in Cavalier King Charles Spaniels and other breeds, but we are fairly convinced that this is an inherited disorder similar to that seen in CKCS.

Macrothrombocytopenia is associated with low platelet numbers and large platelets; however, immune-mediated thrombocytopenia is also often associated with low platelet numbers and large platelets. The difference is that immune-mediated thrombocytopenia is usually associated with clinical bleeding while the inherited disorder in Akitas is not. Also, most immune-mediated thrombocytopenias respond to treatment with steroids. Macrothrombocytopenia in Akitas does not “improve” with any kind of treatment: their platelet numbers and size are their “normal,” which can be confusing at times. Unfortunately the only treatment for immune-mediated thrombocytopenia is steroids; and any time an animal or person is immunosuppressed, they become susceptible to infections.

No one knows what causes this thrombocytopenia in Akitas, and that is what Dr. Hayakawa is trying to determine. In fact, most people don't even know it exists, so hopefully Dr. Hayakawa can gather enough information to publish a paper that describes the disorder so people can be better informed. Right now the only way to distinguish immune-mediated thrombocytopenia from inherited thrombocytopenia is response or lack of response to treatment and also lack or presence of clinical signs. Another diagnosis that must be considered in dogs with low platelet numbers is tick-borne illness. Again, these dogs usually have clinical signs and will respond to treatment with antibiotics.

Several breeds have been diagnosed with inherited macrothrombocytopenia including Chihuahuas, Labradors, English Toy Spaniels, Labradoodles, Poodles, Shih Tzus, Jack Russells, Havanese, Maltese, CKCS, Cairn Terriers, and Norfolk Terriers. I’m sure there will be others. All these breeds have been documented to have one of two different mutations that have been identified in the gene encoding beta1-tubulin. We have not been able to document a mutation in beta1-tubulin in Akitas.

We greatly appreciate your offer of help with my project. We would like to collect as many blood samples as possible from Akitas; 1-2ml blood in an EDTA tube and 3-4 unstained blood smears on slides, along with CBC data of platelet count and MPV. The CBC results can be from previous blood draws; they don't have to be taken at the time of the blood draw for the study. Because we believe this is an inherited disorder, we would like to have a copy of the pedigree for each Akita. We would like to collect blood samples from both affected (low platelet count) and non-affected (normal platelet count) Akitas. There is no form to fill out.

Shipping Instructions:
Packing is easy: just wrap the tube in a sealed plastic bag so that if it leaks, the blood is contained. Place the slides in a plastic slide holder if possible. If that is not available, carefully wrap the slides individually in paper towels and place them in a different plastic bag. Wrap both bags with more paper towels or bubble wrap and put them in a box, doesn't have to be large, and ship. Shipping does not have to be overnight; it can be two-day service. Please use UPS or Fed Ex and not USPO. Ice packs are not necessary. Please ensure you include a copy of the dog's pedigree and CBC data of the platelet count and MPV with each package so the inheritance factor can be traced.

We have received samples from all over the world including Europe, England, Canada, South America, Japan, and Australia for a variety of platelet studies that we are involved in. There really is no problem with shipping samples from overseas as long as a courier is used that is also present in the United States, such as UPS or Fed Ex. Problems occur when the courier is not available in the US and the US postal service has to deliver it once it arrives in the this country. Samples have been delayed for months once they hit our shores if the US postal service becomes involved. I try to have the Europeans use the form I have included in the link below to avoid problems with shipping. Many do not use the form and most do not have problems. I still recommend the form be used.

http://www.vetmed.auburn.edu/uploads/fd/10/fd106e2a06dfda615d7ef3bc5b6dcc66/International_Shipping_Instructions.pdf

Send Shipments to:
Dr. Mary K Boudreaux
Department of Pathobiology
166 Greene Hall
College of Veterinary Medicine
Auburn University
Auburn, Alabama 36849-5519

Teresa has a FedEx Account number for shipping if you need the shipping picked up. Please contact her at SnowCrestAkitas@yahoo.com if you need this.
Thanks!!

Teresa
www.SnowCrestAkitas.com

Comments

  • edited May 2013
    Thanks for posting this information here! I don't know if anyone is dealing with this, but it is always good to get more information, and also to add to the knowledge about potential health concerns in the breed(s).

    And just to be clear, blood samples are needed from both affected and nonaffected dogs? I would be willing to contribute a sample if that is the case, and I hope other people will as well.
  • edited May 2013
    The admitting ER vet was very worried about Angi's low platelet count and it being immune-mediated. They did some clotting tests and something else to determine if it was autoimmune. I don't remember what exactly, they really did like 20 tests on her, including parvo twice, lyme disease, rat poison... I dunno what all else! Anyway, the surgeon said she didn't look like a dog with thrombocytopenia when he was operating on her and her platelet count was normal (not even low-normal) a few days later. So yay!
  • @shibamistress, yes, they'd like samples plus pedigree and CBC platelet results from any previous testing from non-affected Akitas, too.

    I became aware of this in 2008 when a co-owned Akita was diagnosed with low platelets by his regular vet. We took him to UC Davis and were told he had "familial thrombocytopenia" and didn't need treatment. Around the same time a littermate was also taken to Davis, diagnosed with thrombocytopenia, and treated as if it were immune-mediated thrombocytopenia, and nearly died. When treatment was stopped, he reverted to being a healthy dog. A friend of my vet has a third littermate with normal platelets. Their dam and several other relatives also have or had low platelets with no health consequences.

    I know of one pup who died when he was mistakenly treated. Several of his relatives also have inherited thrombocytopenia. I've heard of more JAs than AAs with this condition but both are affected.

    I'm glad Angi's better and wasn't treated for thrombocytopenia on top of her other problems!
  • I wonder if there is some sort of "survival benefit" to the low platelets situation. Just an odd thought.
  • I vaguely remember somewhere reading or hearing that the larger platelets accomplish the same job and fewer are needed because they're bigger. But it's all hearsay because I have no idea where I got that notion from.
  • edited May 2013
    I know of two cases involving dogs from JACA. In both cases a manual count significantly increased the number present.

    Linda, since the study asks for Japanese and American Akita pedigrees. "So far, we have noticed that macrothrombocytopenia can occur in both American Akitas and Japanese Akitas "


    I have asked our members, that want to participate in the study, to note that they have Japanese Akitas. Most will be using their UKC Japanese Akita pedigree. IMO that is something that the ACA might want to do as well. If there is a chance that this is found more int the Japanese Akitas and not the American Akitas we should provide this study with the most accurate data as possible.
  • @*Jack Burton,* I'll suggest that to the researchers. You're right--they're not familiar with typical names in the pedigrees of Japanese Akitas and American Akitas. They may also get pedigrees from Japan and from other countries.

    I read that IDEXX has a new, better way of counting platelets that can overcome the difficulty of counting when there's clumping.

    @poeticddragon, I read something like that, too, perhaps about CKCS because they have the most info on macrothrombocytopenia on their health website.

    I'm curious if dogs with immune-mediated thrombocytopenia sometimes or often have other immune-mediated problems.

    @sukoshi_mom, it's an interesting thought but it looks like 8 or 9 breeds have this condition; I think only in CKCS does it affect about 50% of the breed. It may just be a mutation that doesn't give the affected dogs any greater "survival benefit."
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