Diagnostic approach to canine and feline thrombocytopenia. Approccio diagnostico alla trombocitopenia nel cane e nel gatto

Thrombocytopenia is the most common abnormality of primary hemostasis in dogs and cats. We can deal with thrombocytopenia, whether mild, moderate, or severe, both in routine clinical activity and in ICU. Due to the variability of its clinical presentation, the necessary steps for the etiological diagnosis of thrombocytopenia are not always clear. A complete anamnestic investigation, including the patient's hematological history, and an in-depth clinical evaluation provide us with numerous starting points. The first step in the diagnostic approach of thrombocytopenia is to demonstrate platelet counts below the reference range. Accuracy of automated platelet counts is affected by platelet clumping and platelet size and so it is important to verify the problem by examining a blood smear. Although platelet number, and mean volume can be evaluated, they offer little information on the underlying cause, and without other information it is not often possible to navigate among the differential diagnoses (decreased production, loss/use, immune-mediated and nonimmune-mediated destruction, sequestration).