Hematology Exam 4 Flashcards
During myeloid proliferation, how long do cells take to mature in the bone marrow before being released in to circulation?
5 days
Percentage of peripheral blood neutrophils that are typically bands
<5%
Percentage of white cells that will typically be segmented neutrophils and bands
50-70%
What are the 2 groups of neutrophils in the peripheral blood? What is the percentage of each group?
- Circulating neutrophils 50%
- Marginating neutrophils 50%
Neutrophils that are adjacent to the endothelial lining of the vessel and can be mobilized into the blood by epinephrine or go into the tissues via diapedesis
Marginating neutrophils
Macrophages will remove neutrophils in the spleen after how many days?
2 days
What are the types of granules in neutrophils?
- Primary
- Secondary
- Tertiary
Where are primary granules first seen?
Promyelocytes
This granule type is the first to appear in myeloid cells
Primary
This granule type is first seen in myelocytes
Secondary granules
This granule type is not seen with the Wright’s stain.
Tertiary granules
What are other names for the primary granules?
Azurophilic and non-specific
What do the primary granules contain?
Myeloperoxidase
What is the purpose of myeloperoxidase in primary granules?
The enzyme aids in killing microorganisms
In what cell do we first see primary granules?
Promyelocytes
What is the purpose of primary granules?
Activate proteinases to kill bacteria - but, not as effective as secondary granules
What is another name for secondary granules?
Specific granules
TRUE or FALSE
Secondary granules are first seen in promyelocytes
FALSE
secondary granules are first seen in myelocytes
primary granules are first seen in promyelocytes
If primary or secondary granules are absent, what will occur?
Increased or recurrent infections because the cell is unable to kill the bacteria
The primary function of this cell type is the ingestion and destruction of invading microorganisms
Neutrophils
These granules contain lysozymes and other enzymes that hydrolyze bacteria cell walls and help with inflammation
Secondary granules
Where are the majority of granulocytes found?
Bone marrow
What are the steps of phagocytosis in order? (6)
- Chemotaxis
- Opsonization
- Phagocytosis
- Degranulation/fusion
- Killing
- Inflammation
During this step of phagocytosis cells go to the site of infection
Chemotaxis
The term for when a cell passes through a vessel wall between endothelial cells and in to tissue in response to infection
Diapedesis
This step of phagocytosis is when the neutrophil “recognizes” antibody or complement coated organism
Opsonization
The term for a neutrophil ingesting an opsonized organism bu surrounding it and moving it with pseudopods
Phagocytosis
Term for the granules of a neutrophil fusing with a phagosome and activating
Degranulation
Term for a neutrophil reducing oxygen in order to generate hydrogen peroxide
Oxidative or respiratory burst
Myeloperoxidase reacts with the hydrogen peroxide created during the neutrophils oxidative burst and together, what do these form?
Hypochlorous acid (bleach component)
What is the effect of hypochlorous acid on the engulfed microorganism?
Causes lipid damage to microbial membrane
What can occur if granules and metabolites leak to surrounding tissue?
Inflammation that may cause swelling and fever
What granules degrade the extracellular matrix of the neutrophil and act as chemotactic agents?
Tertiary granules
TRUE or FALSE:
A function of the neutrophil is as a source of transcobalamin I
TRUE
Term for when neutrophils leave thread-like structures from unfolded DNA that can trap and kill bacteria
Neutrophil extracellular traps (NET)
Term for the percentage of a cell type based on a 100-cell differential
Relative count
How is absolute count calculated?
Relative % x WBC count
Term for increased number of neutrophils
Neutrophilia
What are the different qualitative neutrophil changes that may be observed in infection?
- Toxic granulation
- Dohle bodies
- Vacuolization
TERM:
Prominent cytoplasm primary granules seen in infection
Toxic granulation
TERM:
Strands of endoplasmic reticulum RNA observed in infection
Dohle bodies
TERM:
Occurs in the cytoplasm due to phagocytosis
Vacuolization
Range for WBC count
3,600 - 10,600/uL
Relative count for neutrophils
50 - 70%
Absolute count for neutrophils
1,700 - 7,500/uL
Relative count for lymphocytes
18 - 42%
Absolute count for lymphocytes
1,000 - 3,200/uL
Relative count for monocytes
2 - 11%
Absolute count for monocytes
100 - 1,300/uL
What are some causes of neutrophilia?
(4)
- Bacterial infections
- Stress
- Inflammation
- Malignant disorders such as leukemias
Term for decreased neutrophil count
Neutropenia
What are some causes of neutropenia?
- Leukemia (typically because of chemotherapy)
- Aplastic anemia
- Infection
TRUE or FALSE:
Children have an inverse segmented neutrophil/lymphocyte ratio
TRUE
Congenital causes of neutropenia
- Failure of production
- Failure of bone marrow to release
- Destruction
- Misdistribution of cells
Causes of acquired neutropenia
- Viral infections
- Depletion of neutrophi storage pool in marrow
- Chemotherapy of other drugs
- Blood malignancies
Relative range for eosinophils
1 - 3%
High numbers of this cell type are seen in allergies, parasitic infections, and some leukemias
Eosinophils
Relative count for basophils
0 - 2%
What do the granules in basophils contain?
Histamine and heparin
A high count of this cell type is observed in CML and other myeloproliferative disorders.
Basophils
This cell type is a receptor for IgE and is involved in anaphylaxis and immediate hypersensitivity
Basophils
High numbers of this cell type are seen in some leukemias, bacterial infections, and rickettsial infections
Monocytes
DEFINITION:
The term used when any white count is >12,000/uL
Leukocytosis
DEFINITION:
Term used when a white cell count is <1,500/uL
Leukopenia
This qualitative deficiency occurs when the cell does not respond to stimuli
Chemotaxis deficiency