Leukon #3: Qualitative Response to Disease Flashcards
Increased Demand for Neutrophils
- Segmented neutrophils, and sometimes, a few bands, are released from the BM into blood in healthy animals
- Increased numbers of non-segmented neutrophils in blood is called a left shift
- If there is an increased demand for neutrophils –> accelerated production –> toxic changes
Neutrophil - Causes for increased toxic changes
- Associated with accelerated granulopoiesis (marrow process)
- -Increased demand
- -Shortened maturation time
- Represent defects in granulopoiesis
- Note: Inflammation does not mean infection
- -Endotoxemia and septicemia (infectious) are strong differential diagnoses
- -Non-infectious causes include: pancreatitis, immune-mediated disease, trauma, etc.
Neutrophil - Toxic changes
- Blue cytoplasm
- Dohle bodies
- Foamy cytoplasm
- Toxic granulation (primary granules) - RARE
- Cellular giantism (giant cells) - RARE
- Donut-shaped nucleus - RARE
Neutrophil - Toxic changes in the blood
- Marrow process (affect on granulopoiesis process)
- Cytoplasmic changes predominate
- -Foamy vacuoles, Dohle bodies, hyposegmented nucleus
- ID as toxic neutrophils
Neutrophil - Toxic changes in the tissues
- Nuclear changes predominate
- ID as degenerate neutrophils
- Cell membrane is full of pores (glassy appearance) –> liquid comes in –> ruptures cell
Neutrophil - Toxic changes - Blue cytoplasm
Description:
- Basophilic
- Diffuse blue color
Significance:
- Retained RNA
- Enzymes normally digest RNA before release
- -If in bands, but not segs –> implies acute change (worsening)
- -If in segs, but not bands –> implies improvement
Neutrophil - Toxic changes - Dohle bodies
Description:
- 1-3 micron cytoplasmic inclusion
- Blue to gray in color
- Often angular, +/- rounded
Significance:
- Retained ribosomes and RER
- Enzymes normally digest these before release
- Cats (+/- horses) may show as only change (physiologic)
- -Less significant if only change in other species
Neutrophil - Toxic changes - Foamy cytoplasm
Description:
-Foamy (fine, indistinct)
Significance:
- Dissolution of granules (auto-digestion, leaky)
- Persistence of large amount of RER
- A more severe change than basophilia or Dohle bodies
Considerations:
- Artifactual change in old sample
- -If foamy without basophilia, may clue into artifact
Neutrophil - Toxic changes - Toxic granulation
Description:
-Prominent pink-purple granules in cytoplasm
Significance:
- Uncommon to rare; mostly found in cats and horses
- Indication of severe inflammation
- May have primary/secondary granule fusion
Consideration:
-Other toxic changes should also be present
Neutrophil left shift with toxic changes
Common causes:
- Infection
- Non-infection
- Immune-mediated
Rare causes:
- Infiltrative bone marrow disorders
- Chronic myeloid leukemia
Neutrophil - Hypersegmentation
Description:
- Neutrophils with greater than or equal to 5 lobes
- Dense chromatin
- Often thin strands connect lobes
Significance:
- Aging change (in blood, prolonged circulation)
- -Glucocorticoid effect (most common)
- -Mechanism unclear
- Dysplastic change
- -Myelodysplasia, myeloid leukemia
- -+/- vitamin B12 deficiency (mainly humans)
Neutrophil - Botryoid Nuclei
- Hypersegmented nuclei with segments arranged peripherally and connected by thin central filaments (towards the middle - like a flower)
- Typical of hyperthermia (damages bone marrow)
- -Karyorrhexis, pyknosis, apoptotic bodies
- –Karyorrhexis = many small pieces (nuclear fragmentation)
- –Pyknosis = shrinkage, condensation of a cell with increased nuclear compactness or density
- -Metarubricytosis without polychromasia
- -Leukopenia, thrombocytopenia, and petechia
Neutrophil - Hyposegmentation
Description:
- Cells between band and seg stage
- Coarse, mature chromatin
- Nucleus is ribbon-like, lacking adequate indentation
Significance:
- Supports some degree of left-shift
- Inflammation
Eosinophil - Degranulation or Gray cytoplasm
Description:
- PMNs with moth-eaten cytoplasm
- Clear granules (vacuoles) rather than pink
- Some have remnants of pink material
Significance:
- Degranulation v. non-staining
- Normal in sighthounds (greyhounds, whippets, etc.)
Considerations:
- Be aware of breeds (sighthounds)
- Confusion: normal v. toxicity
- -Foamy, blue cytoplasm
- Compare with other cells (neutrophils and monocytes)
Reactive lymphocyte or immunocyte
Description:
- Increased quantity of cytoplasm (production)
- Increased basophilia of cytoplasm
- Possible nuclear pleomorphism (differences in nucleus shape)
Significance:
-Chronic antigenic stimulation
Considerations:
- Possibly T or B cell involved
- -Cannot differentiate unless “plasmacytoid”
