Anaplasma platys in canine blood

A platys

Within the far left platelet, there is a cluster of small micro-organisms that stain blue, compatible with Anaplasma platys. The organism can be mistaken for normal platelet granules and vice versa, but the blue color is helpful on a Wright’s stain. Note that several of the platelets are large (macrothrombocytes), supporting a megakaryocytic hyperplasia (response to the thrombocytopenia induced by the organism) (Wright’s stain, 1000x).