Dear Cindy: The following is a cut and paste of a response I have made before on this topic: (There is a reference to a Dr. Jory Olsen in the following text. He is an Internal Medicine Veterinarian who was once on our list a couple of years ago. He had/has a special interest in this disorder and in cavaliers.)
As to a discussion on Thrombocytopenia; I think it is helpful to first note the definition of this term. Thrombocytopenia literally translates to "a decreased number of thrombocytes". Thrombocytes are a type of blood cell that is essential in forming a blood clot. Another name for thrombocyte is a "platelet". If the number of platelets become "extremely low", bleeding disorders can become evident because the low number of platelets cannot perform their blood clotting function. Platelet numbers and function can be interfered with by diseases or substances such as bone marrow failure immune-mediated disorders (e.g. autoimmune hemolytic anemia), toxins, drugs, cancers, comsumptive coagulopathies (e.g. rat poisons), and infectious agents, such as bacterial organisms. (I can't help but think of modified live vaccines here). The "normal" range of platelets is about 200-500. So, when one has " Thrombocytopenia" is means they have decreased platelets (below normal range). Thrombocytopenia can either be "asymptomatic" (showing no clinical symptoms of disease) or "symptomatic" (display clinical characteristics of a disease). Thrombocytopenia can be "idiopathic" (arising spontaneously or from an obscure or unknown primary cause). The Swedish study (P. Eksell, J. Haggstom, C. Kvart & A. Karlsson) studied blood samples of 102 cavaliers. Out of the 102 cavaliers, 32 had a platelet count less than 100 (150-400 was normal range for their lab used) and 4 of those 32 were less than 50. This study finalizes by saying that the clinical significance and pathogenesis (origination and development of a disease) of Thrombocytopenia in the Cavalier King Charles Spaniel is not yet understood. The Canadian study (L.E. Smedile, D.M. Houston, S.M. Taylor, K. Post, G.P. Searcy) was based on the study of 11 "case studies" and its intention was to only study the clinicopathological features of Cavaliers with "Idiopathic, Asymptomatic Thrombocytopenia". These cases were from medical records from 29 North American Veterinary colleges between the years 1983-1993 and all were presented for a variety of clinical problems AND had Idiopathic Asymptomatic Thrombocytopenia.. Final conclusion - no temporal (of or relating to the sequence of time or to a particular time) correlation between vaccination and thrombocytopenia was established; no correlation between mitral valve endocardiosis and Thrombocytopenia has been established; etiology (cause/origin) of Thrombocytopenia identified in CKCSs is unknown. Thrombocytopenia can be congenital; result from platelet sequestration (setting apart/isolate); increased platelet consumption; decreased platelet production; or increased destruction. In evaluating the 11 cases, several of these possibilities were deemed unlikely for various reasonings, but platelet destruction was commented on. Platelet destruction due to ITP (Idiopathic Thrombocytopenia Purpura(?) (hemorrhagic state characterized by patches of purplish discoloration resulting from escaped blood into the skin and mucous membranes - petechia) is a common cause of Thrombocytopenia in dogs; however, definitive diagnosis of ITP is difficult and frequently is made by exclusion of other conditions. The article discusses methods of diagnosing what the clinical forms of Thrombocytopenia were and their responses to therapy. The article states: "The asymptomatic nature of the Thrombocytopenia in the CKCS in this report suggests adequate platelet function. Clinical evidence of hemorrhage commonly does not occur until the platelet count is less than 50x10(9)/L(6). Perhaps the larger-than-normal platelets in the dogs with platelet numbers less than 50x10(9)/L had increased functional capacity; platelet function has been speculated to depend more on total platelet mass (i.e., platelet number x platelet volume) than on actual platelet number. Final conclusion: recognition of Idiopathic, Asymptomatic Thrombocytopenia in the CKCS is important; previous reports indicate incidences as high as 31%; further studies into platelet structure, function and life span and megakaryocyte (found in bone marrow and is considered to be the source of blood platelets) structure, should help to define the underlying pathophysiology of Idiopathic Asympotomatic Thrombocytopenia. All that said, there is no clear understanding of Thrombocytopenia, further study is considered important for the breed and recommended. Because of the uncertainties with this disorder, and the fact that such a diverse range of possibilities can bring about this disorder, i.e. drugs, immune system (over active or under active) responses and anecdotal experiences are varied, it seems only logical to me that we excercise caution in our treatments (of any sort) and that we concentrate of figuring out how to support weak areas. If you think about it, vaccines introduce various forms of bacterial or viral matter into the body with the intent of stimulating an immune system response. The job of the immune system is to fight off infections and reject foreign proteins. The components of the immune system (white blood cells, antibodies and other substances) are designed to act as a "police force" patrolling the body and is designed to recognize "self cells" from "non-self cells". It is this ability that causes the body to reject skin grafts, blood transfusions and organ transplants. The immune system can fail; either by not doing its job or by doing it too well and no one knows "why" the immune system fails or short circuits. The experts can only speculate. One such speculation is the use of multivalent modifed-live vaccines overstimulating the immune system. As I recited in my previous post, Dr. Virginia Luis Fuentes discusses such speculation as says that some investigators believe it is a harmless anomaly seen in CKCS, whereas other investigators believe it is a significant problem and many CKCS live on a knife-edge and may develop a clinically-apparent bleeding disorder at any time. She reinforces the fact that more work is needed to study large numbers of cavaliers over a period of time. Dr. Jean Dodds is a specialist I would refer you to for further information and treatment. Dr. Jean Dodds (for those who don't know who she is) is an internationally recognized authority in veterinary hematology (a branch of biology that deals with the blood and blood-forming organs) and immunology (a science that deals with the phenomena and cases of immunity and immune responses). In a preface to Dr. Dodds' Revised Vaccination Protocol, 1997, she writes: "This schedule is the one I recommend and should NOT be interpreted to mean that other protocols recommended by a veterinarian would be less satisfactory. It's a matter of professional judgement and choice. For breeds or families of dogs susceptible to or affected with immune dysfunction, immune-mediated disease, immune-reactions associated with vaccinations, or autoimmune endocrine disease (e.g. thyroiditis, Addison's or Cushing's disease, diabetes, etc.), the following protocol is recommended." She goes on to relay her recommendations for vaccine type/age of pup; info on what she recommends for boosters and what she does, and does not, vaccinate for and why. She does NOT recommend vaccinating bitches during estrus (in season), pregnancy, or lactation (nursing mothers). She concludes with: "For animals previously experiencing adverse vaccine reactions or breeds at higher risk for such reactions (e.g. Weimaraners, Akitas), alternatives to booster vaccinations should be considered. These include avoiding boosters except rabies vaccine as required by law; annually measuring serum antibody titers against specific canine infectious agents, such as distemper and parvovirus; and homeopathic nosodes. (This last option is considered an unconventional treatment that has not been scientifically proven to be efficacious. However, data from Europe and clinical experience in North America support its use, and controlled studies are underway to test the method under challenge conditions. If veterinarians choose to use homeopathic nosodes, their clients should be provided with an appropriate disclaimer and written informed consent should be obtained.)" My summary of the above info is such that I believe Dr. Dodds does still recommend careful practices in vaccinating; does not say don't vaccinate puppies or adults, although animals with adverse reactions, or breeds with greater risks for reactions, should consider alternatives to booster vaccinations, including avoiding boosters (except rabies) and instead to annually measure serum antibody titers against specific diseases and/or use homeopathic nosodes (not scientifically proven, but clinical experience supports its use). One only need to ask themselves - why did Dr. Dodds feel the need to come up with a new recommended vaccination protocol (bear in mind her field of expertise)? Attention is drawn to immune system responses to vaccines given. I also note the "legal" cautions. Dr. Jory Olsen's post provides (IMO) some sound advice for those who aren't sure what we should, or should not, be doing and bears repeating. It also appears to line up with what Dr. Dodds writes. I might add that these are also my practices. Dr. Jory Olsen wrote: "No one has any proof of association between vaccination and thrombocytopenia so don't hold your breath. It will be difficult to prove. I would not necessarily expect a dog to have normal counts and then be vaccinated and drop. The effects may be slow onset and chronic and low counts may be present before vaccination and be unchanged after vaccination but still be due to vaccination some time ago. It will be difficult to sort out. The safest thing to do is reduce vaccination since we have growing evidence that yearly vaccines are not necessary. The original one year interval is not based on any studies either. Ask to see some proof that your dog needs a yearly vaccine some time and see what you get. If the vaccines do not turn out to be a factor, you have not caused any harm by reducing to a more appropriate vaccination interval. There is a study by an immunologist that shows protection form puppyhood vaccination that last for 7 years of a study and 10 years total so far in the after study follow up. Titers vastly underestimate the duration of immunity and 97-98% of dogs remain with protective titers for distemper at 3 years and 95% have protective titers for Parvo at 3 years. We will not cause rampant disease by reducing the frequency of vaccination. I will never advocate no vaccinations (although some do) because I think they are an important part or protection of our pets as well as ourselves(Rabies)." A CBC (complete blood count) will tell you whether you currently have a dog with Thrombocytopenia. We shouldn't let all of this knowledge cripple us, we should respect it for what it is and act accordingly. Pat Barrington - Barrington Cavaliers (Southern Ontario-Canada) [EMAIL PROTECTED] ========================================================= "Magic Commands": to stop receiving mail for awhile, click here and send the email: mailto:[EMAIL PROTECTED]?body=SET%20CKCS-L%20NOMAIL to start it up gain click here: mailto:[EMAIL PROTECTED]?body=SET%20CKCS-L%20MAIL E-mail [EMAIL PROTECTED] for assistance. Search the Archives... http://apple.ease.lsoft.com/archives/ckcs-l.html All e-mail sent through CKCS-L is Copyright 2002 by its original author.
