Page 244 - WSAVA2018
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 25-28 September, 2018 | Singapore
and fewer spherocytes; this response can be expected to be seen within days to weeks. The subsiding of autoagglutination would allow the performance of
a direct Coombs’ test and thereby permit the direct documentation of anti-erythrocytic antibodies. As glucocorticosteroid therapy is associated with well- known side effects, the initial dose will be tapered by reducing the amount by one-third every 7-14 days and moving toward every other day therapy. In secondary IMHA with appropriate control of the underlying disease, the tapering can be accomplished more rapidly.
Thromboembolic and Other Complications with IMHA
Because of the potential of gastrointestinal ulceration by glucocorticosteroids and other immunosuppressives, gastrointestinal protectants such as sucralfate may be considered. Because dogs with IMHA suffer from an immune deregulation which may have been triggered by an infection and are treated with immunosuppressive agents, these patients are prone to experience infections; it is, therefore, prudent to administer preventative as well as therapeutic antibiotics to these dogs with IMHA on immunosuppressive therapy.
Thromboemboli and DIC are unique serious complications that greatly contribute to the morbidity
and mortality of dogs with IMHA which are not typically seen in humans and cats with IMHA. Although the pathogenesis remains unknown, venipuncture, catheters, confinement, and glucocorticosteroids as well as other immunosuppressive agents may be contributing factors. Thus far, no study has definitively documented any successful prevention and/or management protocol
for these life-threatening hemostatic problems in
canine IMHA. Predisposing factors should, whenever possible, be limited, and adequate perfusion and
tissue oxygenation should be provided with fluids and transfusions or Oxyglobin. Generally, anticoagulation therapy is instituted after there is some evidence or suspicion of thromboemboli. Unfractionated Heparin (dose of 50-300 IU/kg subcutaneously every 6 hours or by continuous intravenous infusion) or Low Molecular Weight Heparin (LMWH; Dalteperin 150 IU/kg sc every 12 hours) are the most commonly used drugs and is used. The replacement of coagulation factors and antithrombin III has not been proven to be beneficial. Antiplatelet agents may also be used and for instance an ultralow dose of aspirin (1 mg kg once daily) has been advocated by a couple of groups, but other studies question its efficacy. Other antithrombotic agents such as modern antithrombotic agents have been used occasionally, but their efficacy and safety remain also unproven.
In conclusion, the successful management of IMHA remains a challenge; immunosuppressive therapies beyond glucocorticosteroids have not been proven to be effective but can be associated with serious side effects. Furthermore, the tendency to inflammation, necrosis and thromboembolism of dogs with IMHA contributes greatly to the morbidity and mortality of dogs with IMHA and effective preventative and therapeutic interventions have not yet been established.
Author’s studies were supported in part by grants from the National Institutes of Health (OD010939) and the AKC Canine Health and other Foundations. Alvedia, Lyon, France provided the immunochromatographic strips for the studies. The author is the director of the non-for-profit PennGen Laboratory offering genetic and hematological testing.
Author: Urs Giger, Veterinary Hospital of the University of Pennsylvania, 3900 Delancey Street, Philadelphia, PA 19104-6010 USA. Phone: 215-898-8830; Email: giger@; Website: penngen.

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