9 – WBC 3 Flashcards
What is leukemia?
- Presence of neoplastic cells in blood
o *any hematopoietic cell line, including erythroid - Bone marrow also contains neoplastic cells
- Chronic or acute
Chronic leukemia
- Cells are mature (can easily be IDed)
- Indole course of disease
Acute leukemia
- Cells are immature (often difficult to ID)
- Animal will die soon without treatment
Since bone marrow is affected in leukemia, what might you see?
- Cytopenias
o Persistently non-regenerative anemia (may need a couple CBCs)
o Neutropenia (no left shift as bone marrow is shut down)
o Thrombocytopenia - if see 2=bicytopenia
- *if all 3=pancytopenia
When might you see a neutropenia?
- Transient (hopefully)
o Peracute inflammation
o Acute, severe inflammation (Degenerative left shift)
o Normal variation (re-check on a different day) - **Persistent
o Immune-mediated
o Idiopathic
o **bone marrow disorders
Bone marrow disorder and neutropenia
- *infectious agents (especially viral)
- Drugs/toxins/radiation
- Immune-mediated
- Necrosis/fibrosis
- Neoplasia
- Genetic disorders (ex. cyclic neutropenia of gray collies)
o Very vulnerable to infection when neutrophils are LOW
Blood cell half-lives: what will you see first and then what follows?
- Neutrophils: 10-15hrs
- Platelets: 5-7 days
- RBCs: 110-120days
When talking about bone marrow disorder causing neutropenia, what are you normally referring to?
- *Stem cell injury
1. Reversible
a. Acute, transient
b. Varying duration
2. Irreversible
Reversible stem cell injury: acute and transient CLASSIC EXAMPLES
- Canine parvovirus and feline panleukopenia/parvovirus infection
- Rapidly dividing cells: bone marrow, GIT
Why do you see neutropenia in canine parvovirus (etc)?
- Stem cell injury and failure of production
o Affects ALL cell lines, but only see neutropenia due to transient injury - Neutrophil consumption in GIT (due to inflammation)
o Often see inflammatory leukogram with marrow recovery
Reversible stem cell injury: varying duration CLASSIC EXAMPLES
- Chemotherapeutic drugs and estrogen
- Idiosyncratic drug reaction
- Ehrlichia (infectious agent)
- *longer durations=other cytopenias may develop
- *irreversible injury may also occur
Irreversible stem cell injury
- LONG duration means other cytopenias develop
o Thrombocytopenia, non-regenerative anemia - Neutropenia=vulnerable to chronic infections
- *monitor for signs of marrow recovery
When should you do a bone marrow evaluation?
- If persistent, unexplained:
o Neutropenia
o Non-regenerative anemia
o Thrombocytopenia - *need to evaluate CBC at same time (peripheral blood)
What are the 2 most common causes of eosinophilia (+ 3 more)?
- Parasitism
- Allergic/hypersensitivity disorders
- Paraneoplastic
- Idiopathic
- Eosinophil leukemia
Paraneoplastic eosinophilia
- Secondary to lymphosarcoma or mast cell neoplasia
Idiopathic eosinophilia
- Infiltrative eosinophilic organ disease
- Ex. bronchopnuemopathy, myositis, gastroenteritis
- Hypereosinophilc syndrome
Eosinophilia
- Tissue eosinophilia may NOT be reflected in peripheral blood
o Eosinophils reside in blood
o Parasites in tissues=evoke a greater response than parasites in blood or intestinal lumen
What are the causes of basophilia?
- Parasitism and allergic/hypersensitivity disorders
o *Often eosinophils increased as well - Basophil leukemia
- Other hematopoietic neoplasia
What are the causes of monocytosis?
- Increased tissue demand for phagocytic cells
o Inflammation, necrosis, granuloma, IM disease, neoplasia, trauma
o *become macrophages in tissues - Physiologic, steroid leukogram
- Monocytic leukogram (UNCOMMON)
What are the causes of lymphocytosis?
- Physiologic
- Vaccination
- Young animals
- Chronic antigen stimulation: Ehrichia
- **lymphocytic leukemia
o CLL (chronic) or ALL (acute) - (hypoadrenocorticism: may or may not have a stress leukogram)
What are the causes of lymphopenia?
- **stress/steroid therapy
- Leakage of chyle
- Immunodeficiency
o Ex. immunosuppressive drugs, radiation
o Hereditary immunodeficiencies
Why might we see a bicytopenia with a lymphocytic leukemia?
- Bone marrow is making all the neoplastic cells=SPACE OCCUPYING MASS
o Other precursors are being PUSHED out as the cancer is taking over
