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tvpjournal.com | July/August 2015 | TodAy's VeTerinAry PrAcTice in-cLinic HeMAToLoGy Peer reviewed 49 poorly granulated forms can be challenging to identify. in dogs, mast cells are associated with a number of diseases as well as mast cell neoplasia 2 ; in cats, the presence of mast cells typically indicates visceral mast cell disease, increasing the concern for neoplasia. 3 Platelets identifcation of platelet clumps, including visual estimation by examination of a blood flm, is essential to verify the accuracy of automated platelet counts because technical problems can interfere with accurate platelet counting. Large platelets are evidence of platelet turnover, which can refect destructive or consumptive processes, such as immune-mediated thrombocytopenia, infammation, and disseminated intravascular coagulation. Keep in mind that an expanding number of breeds have congenital macrothrombocytopenia initially characterized in cavalier King charles spaniels; these breeds include norfolk and cairn terriers, chihuahuas, Labrador retrievers, poodles, english toy spaniels, shih tzus, Maltese, Jack russell terriers, Havanese, boxers, cocker spaniels, bichons frises, and some mixed breeds. • due to the fact that the platelet mass in these breeds appears to be relatively normal, with platelet size compensating for the low number of platelets, clinical bleeding is not a characteristic of the syndrome. • Presence of persistent moderate thrombocytopenia, appearance of large platelets, and lack of history of unusual bleeding likely indicates this syndrome. • When a plateletcrit is available, it should be normal or just below the reference interval. 4 • Genetic testing can be performed at Auburn University to confirm this diagnosis in breeds in which this genetic mutation has been characterized. 5 COMMON PATTERNS TO RECOGNIZE Regenerative Anemia regenerative anemia in the absence of clinical evidence of hemorrhage should prompt careful evaluation of red cell morphology for causes of hemolysis. There is a tendency to presume that hemolysis is the result of immune-mediated hemolytic anemia in dogs, which causes clinicians to overlook less common, but important and treatable, causes that are identifed with blood flm review, such as zinc toxicity and oxidative and Heinz body anemias (induced by, for example, onions, garlic, leeks, skunk musk, and rBc parasites). infammatory leukograms often accompany hemolytic anemia, and platelet numbers should be scrutinized to identify concurrent immune-mediated thrombocytopenia or the potential for disseminated intravascular coagulation. Nonregenerative Anemia While mild nonregenerative anemia is frequently a nonspecifc response to chronic disease, more severe nonregenerative anemia can indicate bone marrow disease. in addition to evaluating the patient for other cytopenias, it is important to examine the blood flm carefully for morphologically abnormal cells that may signal malignancy. Other Morphologic Abnormalities Patients with signifcant infammation and circulating neoplastic cells may have normal total white cell counts, and automated analyzers perform poorly when identifying morphologic abnormalities. Be sure to avoid the pitfall of assuming normal July/August 2015 | TodAy's VeTerinAry PrAcTice Continued on page 53