Hematopoiesis and CBC Flashcards
Hematapoiesis
(Definition, 3 categories)
Process of blood cell production and development
- Erythropoiesis
- Leukopoiesis
- Thrombopoiesis
Hematopoietic Lines
(list 2, clinical significance)
Maturation Lines:
- Lymphoid cell line
- Myeloid cell line
Significance: A disease to a lymphoid or myeloid stem cell can cause very different diseases. Myeloid stem cell compromise is often more profound, as it precurses many more cells than the lymphoid line
Hematopoiesis Location
(first 10 gestational months)
General Progression (see picture for more accurate description):
- 1st mo: yolk sac only
- 2nd mo: yolk sac declining, liver taking over c help of spleen
- 3rd mo: mostly liver, some spleen
- 4th mo: still overwhelminly liver, declined spleen, BM and liver start prdctn
- 5th mo: declining but dominating liver, stable spleen, rapidly inc. BM, slowly inc. lymph nodes
- 6th mo thru 10th month: liver and spleen declining as BM takes over (7 mo) c some assistance from the lymph nodes
Erythropoiesis
(6 stages)
- Pronormoblast
- Basophilic normoblast
- Polychromatophilic normoblast
- Orthochromatic normoblast
- Polychromatophilic erythrocyte (exposed c special stain as reticulocyte here)
- Erythrocyte
Polychromatophilic Erythrocyte
(cell line, size, nucleous and cytoplasm descriptions, location)
Size: 7-10 microns (same size as lymphocyte, compare against lymphocyte to eval RBC size)
Cell line: Erythropoietic cell
Nucleus: None!
Cytoplasm: blue-gray to pink-gray
Location: In circulation
Just know they exist and should be nucleated in the BM
Mature Erythrocyte
(cell type, size, neucleous and cytoplasm descriptions)
Cell type: Erythropoietic cell
Size: 7-8 microns (easy to measure by comparing to lymphocyte)
Nucleus: None
Cytoplasm: Pink c central palor due to bionclave disc shape. Pallor should take up ~1/3 of cell
Reticulocyte
(Structure, Maturation, Evaluation, Clinical Significance)
Structure: Immature anucleated RBC that contains increased amounts of RNA
Maturation: Released into BM c reticulum (free RNA) within 24 hours of release
Evaluation: Supravital stain (ex: new methyene blue)
Signiciance: Assess erythopoietic activity of BM
Reticulocyte Count Aspects
(Describe 4 values reported)
- Absolute retic count - # per mL of whole blood
- Percent retic - expressed as percentage of total RBC
- Corrected retic - Used in anemic states to better assess RBC production
- RPI - Corrects for premature release of younger retics from the marrow
Note: reticulocytes should be ~1% of circulating RBC count
Myelopoiesis
(list 4 cells produced by this method)
- Neutrophils
- Eosinophils
- Basophils
- Monocytes
Myelopoietic Cell Storage and Delivery Times
(Both in marrow and peripheral tissue)
- Marrow Storage: 7 - 11 days
- Peripheral Storage: 7 hours
- 50% circulate
- 50% marginate
Granulocyte Maturation
(6 stages)
- Myeloblast
- Promyelocyte
- Myelocyte
- Metamyelocyte
- Band
- Segmented (Polymorphonuclear) Cell
Myeloid Margination
Large cells roll around the vessels and tissues until they find a spot to stick until activated.
Band Neutrophil
(size, nucleous and cytoplasm descriptions, normal % of [neutrophil], clinical signif.)
- *Size:** 10 - 16 microns
- *Nucleus:** narrow band of uniform thickness, horseshoe-shaped or ribbon-shapped (if curled on top of itself); clumped chromatin
- *Cytoplasm:** tan to pink; contains specific granules
% Concentration: Normally 8-10% of neutrophils, 1st stage in peripheral blood
Significance: Increased presence of band cells usually indicates an acute leukemia.
Neutrophils
(function, % [leukocytes])
Function: Leave vessels and migrate to tissue damage/infection to phagocytize and kill invading organisms
% [Leukocytes]: 55-65%
Eosinophil
(structure, function %[leukocytes])
Function: Associated with allergic reactions, parasitic infections, and chronic inflammation
Structure: Granules have cytotoxic effect on parasites and bacteria, stimulate release of histamine from basophils and mast cells
%[Leukocytes]: 2 - 8%
Basophil
(structure, function, %[leukocytes])
Function: Mediate inflammatory responses, especially hypersensitivity and allergic responses
Structure: Enzymes contained in granules are vasoactive, bronchoconstrictive, and chemotactic
%[Leukocytes]: 0 - 1%
Monopoiesis
(3 stages)
- Monoblast
- Promonocyte
- Monocyte (only stage in circulation)
Monoblast
(size, nucleous and cytoplasm descriptions)
- *Size:** 12 - 20 microns
- *Nucleus:** large, minimally indented; fine lacy chromatin; 1 -3 nucleoli
- *Cytoplasm:** deep blue, agranular
Note: “Blast” cells are usually reported in one value, as they are difficult to differentiate
Monocyte
(size, nucleous and cytoplasm descriptions, maturation, function, %[leukocytes])
- *Size:** 15 - 18 microns
- *Nucleus:** folded, lobular; irregular in shape
- *Cytoplasm:** abundant, pale blue with red dust-like particles; may contain vacuoles
Maturation:
- Remain in the bloodstream for approximately 14 hours before entering the tissues
- In tissues, transform into macrophages
Function:
- Phagocytize microorganisms, cellular products (later recycles many of these products)
- Secrete substances that affect lymphocyte function
%[Leukocytes]: 2 - 8% of leukocytes
Monocytosis Causes
(7 conditions)
- Neoplastic disorders
- CML
- CMML
- Hodgkins
- Inflammation
- Immune disease (like RA or lupus)
- Collagen disease
- Infection (TB, syphillis)
Lymphopoiesis
(3 stages)
- Lymphoblast (reported as nonspecific “blast” cell)
- Prolymphocyte
- Lymphocyte
Lymphocyte
(size, nucleous and cytoplasm descriptions, functions, %[leukocyte])
- *Size:** 7 - 10 microns (great ruler for RBC size)
- *Nucleus:** round, condensed, homogenous
- *Cytoplasm:** light blue, varies in amount, granules usually absent
Functions:
- Humoral response - B cells - bone marrow
- Cellular response - T cells - thymus
%[Leukocyte]: 25 - 35%
Reactive Lymphocytes
(2 types, structure, functions - include 7 specifics)
Cell Types:
- Reactive/atypical lymphs
- Plasma cells (from B-cells)
Structure:
- contain parachromatin “ballerina skirts”
- may resemble blast cells
- Eccentric nucleus, deep cytoplasm (antibody producing), perinuclear halo, dark chromatin-condensed
Function: Specific immunity, especially against viruses
- Viral disorders
- Infectious mono
- Pertussis (this is a bacteria)
- Toxoplasmosis (cat, infultrate rat and human brains)
- Chicken pox
- Measules
- Chronic infections
- Malignant lymphoproliferative disorders
WBC Examination
(2 categories, 2 exam. points for each)
- Quantitative
- Leukocytosis, leukopenia
- Absolute vs. relative
- Qualitative changes
- Nuclear
- Cytoplasmic
Factors Affecting Neutrophil Distribution
(3)
- Influx - production and release
- Circulating vs. marginal (infection or stress if circulating > marginal)
- Exit from blood into tissues
Physiologic Leukocyte Activation
(define, 3 causes)
Definiton: Causes a distribution change (increase in circulating, decrease in marginal)
Note: While leukocyte count is elevated, it is much less dramatic than a pathologic leukocyte increase
Causes:
- Severe exercise
- Stress, fear, anger
- Hypoxia
Pathologic Leukocyte Activation
(define, 7 causes in 2 categories)
Definiton: Leukocyte distribution changes throughout infection progression
Note: This leukocyte number change is much more dramatic than physiologic leukocyte change. Numbers can reach hundreds of thousands
Causes:
- Leukemia
- Acute
- Chronic
- Infection
- Toxins, (uremia, spider bite, Pb poisoning)
- Tissue necrosis (MI, burns)
- Malignant neoplasm
- Hemorrhage, especially in gut
- Acute hemolysis
Pathologic Leukocyte Count Progression
- Response to infection
- Increased WBC - higher WBC indicates good response
- Left Shift
- Decreased eosinophils
- Recovery from infection
- Decrease neutrophils
- Increase monos
- Increase lymphs, eos
*Decrease results from cell migration into tissues *
Factors Influencing Pathologic Leukocyte Response
(3)
- Age
- Nutritional status
- Kind of invading organism
Toxic Neutrophil Changes
(3 changes, 4 causes, 1 explaination of causes)
Changes:
- Toxic granulations - immature azurophilic granules due to rapid WBC production. Trying to pump out extra cells to fight the tissue distrubance but not leaving enough time for maturation
- Dohle bodies - cytoplasmic, residual RNA
- Cytoplasmic vacuoles - contains phagocytized material
Causes:
- Infection
- Poisoning
- Burns
- Chemotherapy
Explaination: These are reactions to rapidly increased production and action.
Pictured: Dohle Bodies
Left Shift
(define, significance)
Definition: Presence of excess band forms (>10% circulating WBCs) -or- immature neutrophils in circulation
Signif: indicates bacterial infection. Trying to produce extra WBC to respond to acute infection but not allowing them enough time to mature in BM
Complete Blood Count Tests
(8)
- White blood cell count
- Red blood cell count
- Hemoglobin
- Hematocrit
- MCV
- MCH
- MCHC
- Platelet count
Notes:
- *MCV, MHC, and MCHC are called “indices” *
- *Normal values will be reported by each laboratory to account for variability in equipment and environment. While there are general norms, these values should be benchmark for comparison. *
Hemoglobin
(definition, normal values)
Definiton: Protein in RBC which carries O2 to tissues and CO2 the lungs
Normal values:
- Male adult: 13.5 - 17.5 g/dL
- Female adult: 12.0 - 16.0 g/dL
Hematocrit
(definition, normal values, 3 “normal abnormal” situations + explainations)
Definitnion: Percent of RBC volume in whole blood
Normal values:
- Male adult: 41 - 53%
- Female adult: 36 - 46%
”Normal Abnormals,” Reference range higher in:
- High altitudes - more RBC due to lower oxygen concentration in the air
- Smokers/COPD patients - damaged lungs cannot absorb adequate oxygen, body reacts to hypoxia by increasing number of RBCs
- Newborns
Uses for Hematocrit Evaluation
(5)
- anemia (decrease of red blood cells)
- polycythemia (increase in red blood cells)
- dehydration
- blood transfusion decisions
- the effectiveness of those transfusions.
RBC Indices
(list 3, definitions, normal values)
- Mean Cell Volume (MCV)
- Average volume of RBC
- Normal values = 80-100 fL
- Increased - macrocytic
- Decreased - microcytic
- Mean Cell Hemoglobin (MCH)
- Average weight of hemoglobin in RBC
- Normal = 27-31 pg
- Increased - macrocytic anemias and some spherocytoses
- Decreased - microcytic aneia and normocytic hypochromic anemia
- Rarely Used
- Mean Cell Hemoglobin Concentration (MCHC)
- Average expression of hemoglobin per RBC
- Normal = 32-36%
- Increased - hyperchromia (spherocytes)
- Decreased - hypochromia
Clinical Significance of Reticulocytes
Reticulocyte count can evaluate the integrity of your hematopoietic system. The number of RBCs getting produced can change in certain conditions. Suspect the following, given the reticulocyte evaluation:
- Low - May be a bone marrow problem, difficulty in producing more RBC
- Normal - Functioning bone marrow, often valuable information when evaluating for hemolytic anemia
- High - Overactive bone marrow. While this is expected in some instances (high altitudes, infancy, smokers), others may indicate hemorrhage, hemolytic anemia, or inability for the body to recognize oxygen
Clinical Significance - Hemoglobin
Since hemoglobin carries oxygen, an impaired or deficient amount of hemoglobin will prevent oxygenation of tissues. This presents in body-wide hypoxia, or anemia.
