TABLE 65-2.

Leukocyte Cytoplasmic Inclusions

INCLUSION	CELL(S) AFFECTED	KEY MORPHOLOGIC FEATURES	REFERENCES
Bacteria	Neutrophils, monocytes, eosinophils (rarely)	Dogs, cats: positively or negatively staining rods or cocci	Tvedten et al. (1990)
Hepatozoon spp. gametocytes	Neutrophils or monocytes	Dogs: oval, unstained to pale blue basophilic inclusions (5-10 μm)	Barton et al. (1985), Panciera et al. (2000)
Canine distemper virus	Leukocytes (particularly lymphocytes), red blood cells	Dogs: round to irregularly shaped, homogeneous, blue-gray to magenta, intracytoplasmic inclusions	McLaughlin et al. (1985)
Histoplasma capsulatum	Neutrophils, monocytes, eosinophils (rarely)	Dogs, cats: round to oval, uniform, basophilic yeast (2-4 μm) with dark central area and clear halo	Clinkenbeard et al. (1988a, 1988b)
Ehrlichia spp. morulae	E. ewingii, E. equi, or human granulocytotropic Ehrlichia spp.: neutrophils and eosinophils E. canis: monocytes, lymphocytes	Dogs: magenta to basophilic inclusion (2-6 μm) resembling a mulberry	Cowell et al. (1988), Rikihisa (2000)
Leishmania spp. amastigotes	Neutrophils	Dogs: 1-2 small, round to oval organisms with oval nucleus, basophilic ventral kinetoplast, and light blue cytoplasm	Schultze (2000)
Hemosiderin	Neutrophils and monocytes	Dogs: brown crystals (1-4 μm) that stain positively with Prussian blue stain; reported with immune-mediated hemolytic anemia	Gaunt and Baker (1986)