Clinical Hematology Overview Flashcards
1
Q
The total volume of blood in an average adult is about?
A
6 L, or 7% to 8% of the body weight
2
Q
In the total volume of blood about what % is composed of red blood cells, white blood cells, and platelets?
A
45%
3
Q
In the total volume of blood about what % is composed plasma?
A
55%
4
Q
Approximately what % of plasma is water?
A
90%
5
Q
Soluble biochemicals is what % of plasma?
A
10%
Examples:
- proteins
- carbohydrates
- vitamins
- hormones
- enzymes
- lipids
- salts
- and trace metals
6
Q
What is another term for the production of red blood cells?
A
Hematopoiesis
7
Q
Blood cell differentiation and maturation occur primarily in what environment?
A
Bone Marrow
8
Q
How many days do erythrocytes need for maturation?
A
3 to 5 days
9
Q
What are the 6 stages of development for an RBC?
A
Rubriblast > Prorubricyte > Rubricyte > Metarubricyte > Reticulocyte (bluish hue) > Erythrocyte
10
Q
Mature RBCs have a total life span of how many days?
A
120 days
11
Q
Worn-out RBCs are broken down by what system?
A
Mononuclear Phagocytic System
12
Q
The process by which a cell engulfs and digests foreign material is called what?
A
Phagocytosis
13
Q
What are the cells which are located in the blood sinusoids and their primary function is to remove worn-out RBCs.
A
Mononuclear Phagocytes
14
Q
What is the portion of Hb to which a molecule of oxygen binds?
A
Heme (iron)
15
Q
The concentration of _____ in the blood is a measure of its capacity to carry _____, on which cells are absolutely dependent for energy and therefore life.
A
hemoglobin, oxygen
16
Q
This term is derived from the diagrammatic representation of cell maturation, in which the more immature forms are shown on the left side.
A
Shift to the Left
17
Q
After being released in the peripheral blood from the marrow these cells are in circulation for about 10 hours.
A
Neutrophils
18
Q
In terms of cell size and cytoplasm, as a cell matures there is a progressive decrease in size, cytoplasm, and in the intensity of blue color because of loss of what?
A
RiboNucleic Acid (RNA)
19
Q
Name the 3 granulocytes.
A
Neutrophil, Eosinophil, Basophil
20
Q
The granulocytes begin forming with what type of blast?
A
Myeloblast
21
Q
What stage of development comes prior to a basophilic and neutrophilic myelocyte?
A
Promyelocyte
22
Q
At what stage of development can one tell the difference between an eosinophil and a neutrophil?
A
Myelocyte
23
Q
When are eosinophils most active?
A
allergic reactions and certain parasitic infections of the tissues
24
Q
What is the approximate life span of an eosinophil once released into the peripheral blood from the marrow?
A
8 hours
25
Basophilic myelocytes are recognizable due to what feature?
Basophilic Granules
26
What is the approximate life span of *neutrophils* once released into the peripheral blood from the marrow?
10 hours
27
Which of the 3 granulocytes occurs in very low numbers with a mean of 0.6%?
Basophils
28
What is the approximate life span of a basophil once released into the peripheral blood from the marrow?
approximately 8 to 10 hours
29
Which *granulocyte* is thought to contribute significantly to the local inflammation associated with IgE-dependent immune responses to parasites?
basophil
30
What are the 3 substances the granules within a basophil are made of?
1. heparin
2. histamine
3. and perioxidase
31
List the 3 stages of development for monocytes.
Monoblast \> Promonocyte \> Monocyte
32
Approximately how long do *monocytes* remain in the peripheral blood after leaving the bone marrow?
Hours to days
33
When does a monocyte transform into a macrophage?
When they move into the body tissues.
34
Approximately how long do macrophages remain in the tissues?
Months
35
Which cell interacts with lymphocytes in the synthesis of antibodies?
Macrophage
36
How do macrophages assist T cells?
They process and deliver antigens to T cells.
37
What are the 5 stages of eosinophil development?
Myeloblast \> Eosinophilic Myelocyte \> Eosinophilic Metamyelocyte \> Eosinophilic Band \> Eosinophil
38
What are the 3 stages of platelet development?
Megakaryoblast \> Megakaryocyte \> Platelet
39
What are the 6 stages of neutrophil development?
Myeloblast \> Promyelocyte \> Neutrophilic Myelocyte \> Neutrophilic Metamyelocyte \> Neutrophilic Band \> Neutrophil
40
What are the 4 stages of basophil development?
Myeloblast \> Promyelocyte \> Basophilic Myelocyte \> Basophil
41
What are 2 types of lymphocytes?
T-cells (T lymphocytes) and B-cells (B lymphocytes)
42
What is another term for platelet?
thrombocyte
43
Where do T-lymphocytes mature in the body?
thymus
44
What is the diameter of an RBC?
7 to 8 µm
45
When an RBC extrudes its nucleus it changes from _____ to _____ on a Wright-stained blood film.
blue to orange
46
An RBC that has just extruded its nucleus is called what?
reticulocyte
47
The number of _____ in the peripheral blood is an indication of the degree of RBC production by the marrow.
reticulocytes
48
About what percent of the circulating RBCs are reticulocytes?
1%
49
What is another term for when a reticulocyte squeezes through the openings in the endothelial cells lining the marrow cavity?
insinuating
50
In Wright's-stain what colors do reticulocytes appear to be?
pink-grey or pale purple; they have a slight bluish tinge
51
What 6 measurements are taken in a Complete Blood Count (CBC)?
1. Hb
2. Hematocrit
3. RBC count w/ morphology
4. WBC count w/ differential
5. Platelet estimate
6. RBC Indices
52
What are the 3 RBC indices?
1. Mean Corpuscular Volume (MCV)
2. Mean Corpuscular Hemoglobin (MCH)
3. Mean Corpuscular Hemoglobin Concentration (MCHC)
53
What are the 3 commonly used anticoagulants used in hematology?
1. EDTA (K3, Tripotassium Ethylenediaminetetraacetic Acid)
2. Heparin
3. Sodium Citrate
54
Identify the anticoagulant used in these tubes.
EDTA (K3, Tripotassium Ethylenediaminetetraacetic Acid)
55
What is the mode of action for EDTA?
It removes ionized calcium (Ca2+) through the process of **chelation**.
56
What type of anticoagulant does this tube contain?
heparin
57
Of the 3 commonly used anticoagulants used in hematology which is considered an inappropriate anticoagulant for many tests due to Wright-stained smears staining too blue?
heparin
58
What is the *preferred* anticoagulant for the Osmotic Fragility Test?
heparin
59
The MCV represents the ________ or ________ of the average RBC.
volume or size
60
What is another word for corpuscular?
Cell
61
MCV measures the ________ of an RBC.
volume (or size)
62
The MCHC represents the ________ concentration or ________ of the average RBC.
hemoglobin concentration or color
63
What does MCHC stand for?
Mean Corpuscular Hemoglobin Concentration
64
The MCH represents the ________ of hemoglobin in the average RBC.
weight
65
What does MCH stand for?
Mean Corpuscular Hemoglobin
66
What is the derived measurement determined electronically for the measurement of the degree of the variability in RBC size?
Red Cell Distribution Width
67
What does RDW stand for?
Red Cell Distribution Width
68
One RBC contains approximately how many molecules of Hb?
200-300 million molecules
69
How many hemes are inside one molecule of Hb?
How many atoms of iron does *each* heme hold?
How many atoms of oxygen can one molecule of hemoglobin?
4 hemes
1 atom of iron
4 oxygen atoms
70
Each Fe2+ atom is surrounded by a heme moiety which is also known as a \_\_\_\_\_\_\_\_.
Protoporphyrin Ring
71
How many atoms of O2 can 1 molecule of Hb hold?
4
72
Attached to each heme is a globulin aka a \_\_\_\_\_\_\_\_. A globulin is a large, folded chain of \_\_\_\_\_\_\_\_.
polypeptide chain, amino acids
73
How many polypeptide chains (globulins) are in 1 molecule of Hb?
4
74
The principle adult Hb is \_\_\_\_\_\_\_\_.
Hb A
75
Hb A contain what types of globin chains?
2 alpha
2 beta
76
What is an additional form of adult Hb?
Hb A2
77
What are the chains substituted in A2?
Beta for Delta
78
What is the major form of Hb found during intrauterine life and at birth?
Hb F
79
What are the substitutions in Hb F?
2 Beta chains for 2 Gamma chains
80
Disorders in which the presence of structurally abnormal hemoglobins is considered to play a role pathologically are called \_\_\_\_\_\_\_\_.
hemoglobinopathies
81
Most hemoglobinopathies are the result of what type of chain abnormalities?
beta-chain abnormalities
82
What are the 4 clinically important abnormal hemoglobins?
1. Hb S
2. Hb C
3. Hb D
4. Hb E
83
What is the most common abnormal Hb?
Hb S
84
Which abnormal Hb is predominantly found in the black population and is responsible for sickle cell anemia?
Hemoglobin S (Hb S)
85
Which abnormal Hb is likely from the following data?
* May occur in homozygous or heterozygous state
* RBCs may appear as *target cells*
* Crystals of precipitated Hb may be seen
Hb C
86
Define oxyhemoglobin.
A Hb molecule fully saturated with 4 oxygen molecules.
87
Define reduced hemoglobin.
A Hb molecule returning from the lungs with carbon dioxide (CO2).
88
What is carboxyhemoglobin (HbO2)?
When Hb combines with carbon monoxide (CO).
89
Why does carbon monoxide poisoning occur?
Hb has an affinity for CO (200x greater than O2) and when paired together oxygen cannot be carried leading to asphyxiation.
90
What is the cell maturation of a lymphocyte?
Lymphoblast \> Prolymphocyte \> Lymphocyte
91
What cells develop from a lymphocyte?
NK Cell, B Cell, T Cell
92
What type of cell does a plasma cell develop from?
B Cell
93
Which *flat bones* contains active adult hemopoietic tissue (colony forming units in red marrow)?
1. Skull
2. Vertebrae
3. Sternum
4. Ribs
5. Pelvis
94
\_\_\_\_\_\_\_ is an iron-binding protein that *transports* iron in the blood and other fluids.
Transferrin
95
What is the *major form of iron storage*.
Ferritin
96
\_\_\_\_\_\_\_\_: an H2O insoluble form of iron storage derived chiefly from the *breakdown of erythrocytes*.
Hemosiderin
97
What are the early *heme* precursors?
Early Precursors:
1. **Delta** (δ) Amino-la-evulinic Acid
2. **Porpho**-bilinogen
98
What are the **late** *heme* precursors?
* Uro-porphy-rinogen
* Copro-porphy-rinogen
* Proto-porphy-rin
* HEME + 4 globin
99
When excess iron is stored in tissues and body organs it leads to what 2 conditions?
Hemochromatosis and Hemosiderosis
100
What is the difference between hemochromatosis and hemosiderosis?
Hemochromatosis is an *inherited* condition that causes you to absorb too much iron from food.
Hemosiderosis is an overload of iron in your organs or tissues resulting from bleeding within an organ or area of tissue and/or red blood cells breaking down within your bloodstream.
101
What are conditions/symptoms as a result of enzyme deficiencies from the *early* heme precursors?
**Neuropsychiatric P****orphyrias** that typically cause nervous system symptoms i.e. Acute Intermittent Porphyria (AIP)
102
What types of porphyrias can arise from enzyme deficiencies from the *late* heme precursors?
**Cutaneous P****orphyrias** i.e. skin symptoms such as photosensitivity, excessive hair growth in affected areas
103
What symptom does acute and cutaneous porphyria share?
red or brown colored urine aka “port wine”
104
What is the name of the *inherited* condition that causes you to absorb too much iron from food that leads to serious conditions such as diabetes, heart problems and liver disease.
Hemochromatosis
105
What is the name of the condition which is caused by an overload of iron in your organs or tissues often as a result from bleeding within an organ or area of tissue, and red blood cells breaking down within your bloodstream.
Hemosiderosis
106
What are the male and female hemoglobin reference ranges?
* Male: 16 ±2g/dl
* Female: 14 ±2g/dl
107
\_\_\_\_\_\_\_\_ measures packed cell volume in percent.
Hematocrit
108
What is the microhematocrit method?
A fingerstick using EDTA or heparinized sample.
109
The automated hematocrit method is calculated from ________ and \_\_\_\_\_\_\_\_.
MCV and RBC
110
The following are examples of sources of error for what type of measurement?
* cold agglutinins
* high WBC counts
*Automated* Hematocrit Method
111
What do these reference ranges apply to?
* Male: 47 ±5%
* Female: 42 ±5%
Hematocrit
112
What is the mechanism of action for heparin?
Anti-thrombin agent
113
What is the mechanism of action for EDTA?
EDTA in lavender-top tubes chelates ionized calcium which binds and withholds calcium ions thereby blocking the activation or progression of the coagulation cascade – ultimately inhibiting clot formation.
114
What are examples of errors when measuring hemoglobin resulting in falsely elevated values?
1. Lipemia/Icterus: due to increased turbidity of the sample
2. High WBC count
3. Resisting hemoglobins (i.e. SS, CC)
115
What are examples of errors for the *Microhematocrit* Method?
1. Failure to seal tube properly
2. Incorrect reading due to uneven clay plug
3. Inappropriate centrifuge time/speed
4. Excess EDTA resulting in RBC shrinkage
116
The MCV is calculate by…
manually **dividing the volume of packed red blood cells (hematocrit) by the number of red blood cells then multiplying by 10** to convert the hematocrit reading from volume of PRBCs per 100mL to volume per liter.
(HCT ÷ RBC) × 10 = MCV (fL)
117
If the Hct is 45% and the red cell count is 5 x 1012 cells per liter then what is the MCV?
45 / 5 = 9
9 x 10 = 90 fL
118
The MCH is calculated by...
manually **dividing the hemoglobin by the red cell count** then multiplying by 10 to convert the Hb from grams per deciliter to grams per liter.
(HB ÷ RBC) × 10 = MCH (pg)
119
Calculate the MCH:
* Hb is 15g/dL
* RBC is 5 x 1012 cells per liter
15 x 10 =
150 / 5 = 30 pg
120
The MCHC is calculated by…
manually **dividing the hemoglobin by the hematocrit then multiplying by 100**
(HB ÷ HCT) × 100 = MCHC g/dL
121
The Red Cell Distribution Width Coefficient of Variation (RDW-CV) is calculated by...
(Standard Deviation of MCV ÷ Mean MCV) × 100
122
What are the 5 components of Wright stain?
* Polychrome (Romanowsky) stain
* Phosphate buffer (pH 6.4)
* Eosin
* Methylene blue
* Methanol (fixative)
123
What are the likely sources of error when a stained slide is *too blue*?
* pH buffer or stain is too basic
* prolonged staining
124
What are the likely sources of error when a stained slide is *too red*?
* pH buffer or stain is too acidic
* prolonged washing
125
The Absolute Value is calculated by…
**Absolute Value = (Relative % \* Total Cell Count)**
i.e. for Neutrophils
* total cell count: 6,000/μL
* Relative: 60%
0.6 × 6,000 = 3,600/μL
126
Which cell is increased in *bacterial* infections?
Neutrophils
127
Which cell is increased in *viral* infections?
Lymphocytes
128
Which cell is increased in Tuberculosis, Syphilis, and Malignancies?
Monocytes
129
Which cell is increased in *allergies* and *parasites*?
Eosinophils
130
Which cell is increased in immediate *hypersensitivities*?
Basophils
131
The ________ is the percentage of RBCs in a volume of whole blood. It is expressed as units of percent or as a ratio in the SI system and is used in evaluating and classifying various types of anemias according to red cell indices.
hematocrit (Hct)
132
What type of cell has the following Reference Range and Function?
* Females: 3.8-5.2 x 106 μL (microliter)
* Males: 4.5-6.1 x 106 μL (microliter)
* O2 transport to tissue and CO2 removal from tissue
Red Blood Cell
133
What type of cell has the following Reference Range and Function?
* Relative: 45-70%
* Absolute: 2250-7000/μL (microliter)
* Ingest and kill bacteria
Neutrophil
134
What type of cell has the following Reference Range and Function?
* Relative: 20-40%
* Absolute: 1000-4000/μL (microliter)
* Humoral and cell mediated *immunity*
Lymphocyte
135
What type of cell has the following Reference Range and Function?
* Relative: 3-10%
* Absolute: 150-1000/μL (microliter)
* Ingest and kill bacteria, digest debris, initiate and regulate adaptive immune response
Monocyte
136
What type of cell has the following Reference Range and Function?
* Relative: 0-2%
* Absolute: 0-200/μL (microliter)
* *Inflammatory* response mediator
Basophil
137
What type of cell has the following Reference Range and Function?
* Relative: 0-3%
* Absolute: 0-300/μL (microliter)
* *Allergic* response regulator, specific *parasitic* infections
Eosinophil
138
What type of cell has the following Reference Range and Function?
* Relative: N/A
* Absolute: 15,000-400,000/μL (microliter)
* Clotting
Platelet (thrombocyte)
139
The ________ is the average volume (or size) of an RBC expressed in \_\_\_\_\_\_\_\_.
Mean Corpuscular Volume (MCV)
femtoliters (fL)
140
Which cell has the following Reference Ranges?
* Relative: 45-70%
* Absolute: 2250-7000/μL
Neutrophil
141
Which cell has the following Reference Ranges?
* Relative: 20-40%
* Absolute: 1000-4000/μL
Lymphocyte
142
Which cell has the following Reference Ranges?
* Relative: 3-10%
* Absolute: 150-1000/μL
Monocyte
143
Which cell has the following Reference Ranges?
* Relative: 0-2%
* Absolute: 0-200/μL
Basophil
144
Which cell has the following Reference Ranges?
* Relative: 0-3%
* Absolute: 0-300/μL
Eosinophil
145
Which cell has the following Reference Ranges?
* Absolute: 150,000-400,000/μL
Platelet
146
What are the Reference Ranges for Red Cells?
* Female: 3.8 - 5.2 x 106/μL
* Male: 4.5 - 6.1 x 106/μL
147
What are sources of error when performing an automated hematocrit?
* Cold agglutinins
* High WBC count
148
What are blood disorders cause by enzyme deficiencies which causes build-up of heme precursors resulting in red or port wine colored urine?
Porphyrias
149
What are the Protoporphyrin Synthesis precursors?
(Hint: There are 6 of them.)
1. Delta Aminolaevulinic Acid
2. Por-pho-bilinogen
3. Uro-porphy-rinogen
4. Copro-phorphy-rinogen
5. Proto-porphy-rin
6. Heme + globin 4 hemoglobins
150
What is the formula to correct the WBC count if nucleated red cells are included in the count?
(WBC # X 100) / (100 + NRBCs) = corrected WBC count
151
Megaloblastic Anemia (B12 and folate deficiency) is associated with what type of WBC morphology?
**Hyper**segmented Neutrophils
152
Pelger Huet (inherited-Acute Myeloid Leukemia), and Pseudo-Pelger Huet (acquired-AIDS) are associated with what type of WBC morphology?
(Hint: it is important to differentiate from bandemia with a left-shifted peripheral blood smear.)
**Hypo**segmented Neutrophils
153
Bacterial infections, Burns, and *Chemotherapy* are associated with what type of WBC morphology?
(Hint: occurs regularly with bacterial infection and often with other causes of inflammation.)
Toxic granulation and Vacuoles
154
Bacterial Infections, Burns, and *May-Hegglin* are associated with what type of WBC morphology?
May-Hegglin Anomaly is a rare, inherited, blood platelet disorder characterized by abnormally large and misshapen platelets (giant platelets) and defects of the white blood cells known as leukocytes.
Döhl Bodies (RNA)
155
Infectious Mono and other Viral Infections are associated with what type of WBC morphology?
Variant Lymphs (increased size and basophilia)
156
What is the RR for MCV?
80-100fl
\<80 microcytes
\>80 macrocytes
157
What is the RR for MCH?
28-32pg
158
What is the RR for MCHC?
32-36% (g/dL)
\<32 Hypochromic cells, Icterus
\>36 Spherocytes, Icterus, Lipemia, Hb SS, CC
159
What is the RR for RDW-CV?
11.5-14.5%
\>14.5% anisocytosis
160
What is the RR for RDW-SD?
39-47fL
\>47fL anisocytosis
161
Identify this abnormal RBC shape.
Acanthocyte
162
What type of abnormal RBC shape is seen in:
* Abetalipoproteinemia
* Severe Liver Disease
Acanthocyte
163
Identify this abnormal RBC shape.
Echinocyte “Burr” Cell
164
What type of abnormal RBC shape is seen in:
* Uremia
* Artifact (alkaline glass effect)
Echinocyte “Burr” Cell
164
What type of abnormal RBC shape is seen in:
* Uremia
* Artifact (alkaline glass effect)
Echinocyte “Burr” Cell
165
Identify this abnormal RBC shape.
Elliptocytes
166
What type of abnormal RBC shape is seen in:
* Hereditary Elliptocytosis
* Iron Deficiency
* Thalassemia
Elliptocyte
167
Identify this abnormal RBC shape.
Macroovalocyte
168
What type of abnormal RBC shape is seen in:
* Megaloblastic Anemia
Macroovalocyte
