RBC Disorders (Part 2) Flashcards

(195 cards)

1
Q

This is a macrocytic anemia in which DNA synthesis is unimpaired.

A

Macrocytic nonmegaloblastic anemia

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2
Q

Macrocytosis tends to be mild; the MCV usually ranges from100 to 110 fL and rarely exceeds 120 fL

A

Macrocytic nonmegaloblastic anemia

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3
Q

This macrocytic anemia lacks hypersegmented neutrophils and oval macrocytes in the peripheral blood and megaloblasts in the bone marrow

A

Macrocytic nonmegaloblastic anemia

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4
Q

Pathologic result of nonmegaloblastic macocytic anemia

A

liver disease, chronic alcoholism, or bone marrow failure

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5
Q

What are the characteristics of a macrocytic anemia? Cite atleast three. (HIPA)

A
  • Hypercellular Bone Marrow
  • Presence of megaloblast
  • Ineffective erythropoiesis
  • Active intramedullary hemolysis
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6
Q

It is where there is an impaired DNA synthesis and many of the cells never undergo mitosis & rather they breakdown and
die in the bone marrow

A

Ineffective erythropoiesis

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7
Q

Cite at least three consequences of ineffective erythropoiesis.

A
  • Bone marrow destructions of erythroid presursors
  • Lack of regeneration of bone marrow elements during anemic stress
    -Lack of nucleated red blood cells in peripheral smear
    -Lack of polychromasia in peripheral smear
  • Reticulocytopenia
  • Intramedullary hemolysis
  • Increased bilirubin and LDH
  • Decreased haptoglobin
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8
Q

What are the two major divisions of megaloblastic anemia?

A

Vitamin b12 (cobalamin, Cbl) deficiency
Folic acid deficiency

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9
Q

It manifests macro-ovalocytes and giant hypersegmented neutrophils

A

Megaloblastic anemia

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10
Q

What causes an impaired DNA synthesis?

A

Vitamin B12 or folate deficiency

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11
Q

If DNA synthesis is impaired what happens?

A

Nuclear replication slows down and each step of maturation will be delayed

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12
Q

If this is prolonged it would results in a large nucleus. Resulting to a megaloblast, large nucleus, increase cytoplasmic RNA, and early synthesis of hemoglobin

A

premitotic interval

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13
Q

Cite the megalocyte maturation sequence

A

Promegaloblast (Megaloblastic rubriblast) >
Basophilic megaloblast (Megaloblastic prorubricyte) >
Polychromatophilic megaloblast (Megaloblastic rubricyte) >
Orthochromic megaloblast (Megaloblastic metarubricyte) >
Polychromatophilic megalocyte (Megaloblastic reticulocyte) >
Megalocyte (Oval macrocyte)

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14
Q

A decrease amount of cells in all cell lines
(WBC, RBC, platelets)

A

Pancytopenia

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15
Q

Megaloblastic macrocytic anemia results to?

A
  • Pancytopenia
  • Increased MCV and MCHC
  • Hypersegmented neutrophils (five lobes or
    more in segmented neutrophils)
  • Increased bilirubin
  • Increased LDH
  • Hyperplasia in the bone marrow
  • Decreased M:E ratio (usually 10:1)
  • Reticulocytopenia
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16
Q

These are cells found in the bone marrow of a patient
with megaloblastic anemia

A

Megaloblasts

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17
Q

It is characterized by a more open chromatin
pattern, karyorrhexis, & multiple Howell Jolly
bodies

A

Megaloblasts

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18
Q

It is a product of maturation arrest or nuclear cytoplasmic asynchrony

A

Megaloblast

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19
Q

This causes the nucleus
and then cytoplasm to not mature together

A

nuclear-cytoplasmic asynchrony

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20
Q

Where does cobalamin absorption takes place?

A

Ileum of the small intestine

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21
Q

It is the only vitamin exclusively synthesized by microorganisms

A

Cobalamin

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22
Q

Form of stored cobalamin in the liver

A

adenosylcobalamin

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23
Q

In order to absorb cobalamin, it requires?

A

Castle’s factor or Intrinsic factor

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24
Q

Cobalamin is transported in the plasma in the form of?

A

methylcobalamin

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25
Transporter of methylcobalamin
transcobalamin
26
Vitamin B12 is otherwise known as?
cyanocobalamin
27
What are the causes of Vitamin B12 deficiency?
- Fish tapeworm Diphyllobothrium latum infection - Pernicious anemia - Malabsorption syndrome caused by gastric resection, gastric carcinoma, and some forms of celiac disease or screw - Nutritional deficiency - Hypochlorhydria
28
It refers to the decrease production of hydrochloric acid in the stomach
hypochlorhydria
29
Hypochlorhydria is associated with?
pernicious anemia
30
It is caused by failure of the gastric mucosa to secrete intrinsic factor
Pernicious Anemia
31
Other term for Pernicious Anemia
Addison’s anemia or Atrophy gastritis
32
Pernicious anemia is an autoimmune disease caused by two antibodies called?
Anti-parietal cell antibodies and Anti-intrinsic factor antibodies.
33
It produces a yellow lemon color of the skin
Pernicious anemia
34
Because pernicious anemia has neurologic symptoms, it has been called as?
Megaloblastic madness
35
It is an autosomally recessive inherited defect in the intestinal absorption of cobalamin
Imerslund-Grasbeck Syndrome
36
There is a problem in the absorption of cobalamin but the intrinsic factor is normal
Imerslund-Grasbeck Syndrome
37
What are the diagnosis used for cobalamin deficiency?
Schilling test Serum Cobalamin Assay Methylmalonic Acid and Homocysteine Assays Deoxyuridine Suppression Test
38
It tests the ability of the patient to absorb an oral dose of radioactive cobalamin
Schilling test
39
It is a microbiological assay which utilizes the organism called Euglena gracilis
Serum Cobalamin Assay
40
It measures the ability of the marrow cells in vitro
Deoxyuridine Suppression Test
41
These both increase in megaloblastic anemia
Methylmalonic Acid and Homocysteine Assays
42
It is considered as the reference procedure for the determination of pernicious anemia
Schilling test
43
In Schilling test, If the abnormal result of stage 1 improves with administration of intrinsic factor, it means that a patient has?
Intrinsic factor deficiency
44
Folate is absorbed where?
Jejunum
45
It cannot be corrected by having vitamin b12 supplementation
folate deficiency
46
This can be partially corrected by folate even in the absence of cobalamin supplementation
Anemia of cobalamin deficiency
47
What are the causes of folate/folate acid deficiency? (CPPS)
- Chronic alcoholics - Poor dietary habits - Pregnancy - Steatorrhea - tropical sprue, nontropical sprue, celiac disease
48
Diagnosis of folate deficiency
- Microbiological assay (definitive) - Serum folate (<3 ug/L) - Red cell folate
49
This test for folate deficiency utilizes the organism Lactobacillus casei
Microbiological assay
50
If the patients has low Vit. B12, normal or high serum folate and low red cell folate the patient has?
Vitamin B12 deficiency
51
If the patient has normal Vit. B12, but low serum folate and red cell folate, the patient has?
Folic Acid deficiency
52
If the patient has low Vit. B12, low serum folate, and low red cell folate, the patient has?
Both Vitamin B12 and Folate acid deficiency
53
How can you spot a megaloblastic anemia?
By looking at the MCV. One of the signs of a megaloblastic anemia is the presence of a high MCV .
54
Aside from a high MCV result what are the other indicators that would confirm that a patient has megaloblastic anemia?
hypersegmented neutrophil plus the presence of macroovalocytes in the peripheral blood smear
55
Termed as "shift reticulocytes”, especially in response to acute blood loss, hemolysis, and bone marrow infiltration
Non-megaloblastic anemia
56
Results in high levels of EPO
Non-megaloblastic anemia
57
Seen in a plastic anemia, refractory anemia, and Diamond-Blackfan anemia
High levels of EPO
58
This macrocyte is seen in folic acid deficiency, vitamin b12 deficiency, and pernicious anemia
Oval macrocyte
59
This macrocyte is seen in alcoholism, hypothyroidism, and liver disease
Round hypochromic macrocyte
60
This macrocyte is seen in neonate response to anemic stress and response to anemic stress
Blue- tinged macrocyte
61
This macrocyte is seen in non-megaloblastic anemia
Round hypochromic macrocyte
62
Reticulocyte stain with supravital stain
Blue-tinged macrocyte
63
This macrocyte is seen in megaloblastic anemia
Oval macrocyte
64
Characterized by Normochromic and normocytic
Myelophthisic anemia
65
Associated with marrow replacement by involvement with abnormal cells or tissue
Myelophthisic anemia
66
Characterized by increased NRBC
Myelophthisic anemia
67
A condition in which bone marrow is replaced by abnormal cells but still the peripheral smear would present a normochromic and normocytic RBCs but there is an increase in the presence of your nucleated RBC
Myelophthisic anemia
68
A condition in which bone marrow does not produce any blood cells
Aplastic anemia
69
Seen in pancytopenia, macrocytosis, increase RDW, and chloramphenicol
Aplastic anemia
70
It is a medication that can commonly cause aplastic anemia
Chloramphenicol
71
An inherited Aplastic Anemia
Fanconi’s Anemia
72
Presence of scattered giant pronormoblasts in the bone marrow
Transient Aplastic Crises
73
Caused by increased levels of Hb F and i antigen
Fanconi’s Anemia
74
Caused by parvovirus B19 infection
Transient Aplastic Crises
75
It is often preceeded by an infection.
Transient Aplastic Crises
76
Not an aplastic anemia but just pure red cell aplasia
Transient Aplastic Crises
77
A condition where there is pancytopenia. Wherein all of the cell lines are affected.
Fanconi anemia
78
An anemia wherein only the red cells are affected
Diamond Blackfan anemia
79
Characterized by congenital Red Cell Aplasia, Macrocytic, low reticulocyte level, elevated Hb F, and the frequent presence of antigen i
Diamond Blackfan Anemia
80
Blood is lost in small amounts over an extended period
Chronic Posthemorrhagic Anemia
81
Transient fall in the platelet count which made the platelet count may rise to elevated levels within 1 hour
Acute Posthemorrhagic Anemia
82
Blood is lost over a short time in amounts sufficient to cause anemia. Reticulocyte increases 3-5 days after blood loss
Acute Posthemorrhagic Anemia
83
Increase red blood cell destruction
Hemolytic anemia (Membrane disorders)
84
The lifespan of normal RBC would decrease if they were transfused into the patient but patient’s red cells survive normally if given to a normal patient
Extrinsic hemolytic anemia
85
Increased hemolysis also results in?
increased LDH
86
This test is to determine whether it (anemia) is immune- mediated or not
Antiglobulin test
87
Patient’s RBC would not survive when transfused to a normal recipient. Defect of RBC itself, and membrane, metabolic, and hemoglobin defects
Intrinsic hemolytic anemia
88
IDENTIFY: hemoglobinemia, hemoglobinuria, or hemosideriuria is absent. Increase in urine or fecal urobilinogen, increase blood carboxyhemoglobin level, and increase indirect- reacting serum bilirubin
Extravascular or Extrinsic hemolytic anemia
89
IDENTIFY: hemoglobinemia, methemalbuminemia, hemoglobinuria, or hemosideriuria is present, there is also an increase in LDH
Intravascular or Intrinsic hemolytic anemia
90
Reversal of the LD isoenzyme pattern is seen with LD1 exceeding LD2
Intravascular or Intrinsic hemolytic anemia
91
Most red cell destruction about 80-90%is presumed to be ________ within macrophages of the mononuclear phagocytic system of the liver and the spleen.
extravascular
92
Identify: MCHC > 36%, decreased surface-area-to-volume ratio, hyperpermeable to sodium thus increase osmotic fragility
Spherocytes
93
IDENTIFY: hemoglobinemia, methemalbuminemia, hemoglobinuria, or hemosideriuria is present. Increase in LDH is also observed
Intravascular or Intrinsic hemolytic anemia
94
IDENTIFY: MCHC > 36%, decreased surface-area-to-volume ratio, hyperpermeable to sodium thus increase osmotic fragility
Spherocytes
95
Most common prevalent hereditary hemolytic anemia among people of Northern European descent
Hereditary Spherocytosis
96
Hereditary Spherocytosis is caused by deficiency of the key membrane protein called?
spectrin
97
Characterized by increase osmotic fragility. An extravascular hemolysis within creased pigment catabolism, erythroid hyperplasia, and reticulocytosis but is DAT (Direct Anti-Globulin Test) negative because its not immune-mediated--it’s a membrane defect
Hereditary Spherocytosis
98
Refers to the weakening of the membrane skeleton and defective association of proteins that hold the skeleton together.
Hereditary Elliptocytosis
99
Deficiency of spectrin is again present but there is also a deficiency in the proteins commonly associated with the ALPHA & BETA-spectrin regions.
Hereditary Elliptocytosis
100
RBCs may even fragment at 37°C, body temperature with prolonged heating
Hereditary pyropoikilocytosis
101
In normal RBC budding and fragmentation show when heated at?
49°C
102
Red cell fragments at 45°C to 46 °C
Hereditary pyropoikilocytosis
103
Characterized by a well-defined band 3 molecular deletion and increased resistance to malaria
Southeast Asian Ovalocytes
104
It is a severe congenital hemolytic anemia, which is characterized by microcytosis, striking micropoikilocytosis and fragmentatin
Hereditary pyropoikilocytosis
105
Appears to have two bars across the center
Stomatocytic Ovalocyte
106
A thinner variant of elliptocytes or ovalocytes
Pencil cells/oat cells
107
Where the red cell is dehydrated due to loss of cations, predominantly K+ and water
Hereditary stomatocytosis
108
MCV is normal or slightly increased and increased MCHC
Hereditary stomatocytosis
109
Opposite of hereditary spherocytosis because there is a decrease in osmotic fragility. MCHC is high
Hereditary xerocytosis
110
Stomatocytes seen on blood smears
Hereditary stomatocytosis
111
Increased surface-to-volume ratio leading to moderate to severe anemia
Hereditary xerocytosis
112
Gene suppression or the present of a silent Rh gene
Rh null Disease
113
This form of acanthocyte-associated hemolytic anemia is seen in patients with established alcoholic cirrhosis
Spur Cell Hemolytic Anemia
114
Increase OFT and autohemolysis
Rh null Disease
115
Marked dehydration and irreversible potassium loss, peculiar red cell morphology where the hemoglobin of red cells seem paddled at one end of the red cell
Hereditary xerocytosis
116
In a peripheral smear you can see stomatocytes and spherocytes
Rh null Disease
117
Caused by autoantibodies that are usually directed at Rh antigens
Warm Autoimmune Hemolytic Anemia
118
Can also be anti-U, anti-LW, and anti-Kell, and JKa or Fya
Warm Autoimmune Hemolytic Anemia
119
Usually anti-I. Complement factors occurs frequently due to M. pneumonia, respiratory infarctions, IMDAT+
Cold Autoimmune Hemolytic Anemia
120
It is the more common autoimmune hemolytic anemia
Warm Autoimmune Hemolytic Anemia
121
Exhibits spherocytosis, schistocytes, polychromasia, and nucleated erythrocytes
Warm Autoimmune Hemolytic Anemia
122
Involves coating of IgG of erythrocytes with or without complement taxation
Warm Autoimmune Hemolytic Anemia
123
Presence agglutination of the patient’s RBC in the capillaries
Cold Autoimmune Hemolytic Anemia
124
Most common medication associated with Cold Autoimmune Hemolytic Anemia
Aldomet
125
Optimal temperature of reactivity of Warm AIHM
37°C
126
Immunoglobulin class of cold AIHM
IgM
127
Site of hemolysis of cold AIHA
Intravascular
128
Optimal temperature of reactivity of Cold AIHM
4°C
129
Immunoglobulin class of warm AIHM
IgG
130
Site of hemolysis of warm AIHA
Extravascular
131
Complement activation of cold AIHA
+ (positive)
132
Complement activation of warm AIHA
positive (+) & negative (-)
133
In Cold Hemagglutinin Disease, Complement is fixed on the red cells during cold temperatures ________ and then red cells agglutinate and hemolyze as body temperature rises, ________
0 to 5 °C and 20 to 25 °C, respectively
134
Decay Accelerating Factor deficiency
Paroxysmal Nocturnal Hemoglobinuria
135
Intermittent (paroxysmal) sleep associated (nocturnal) blood in the urine (hemoglobinuria)
Paroxysmal Nocturnal Hemoglobinuria
136
Also called Donath Landsteiner antibody with anti-P specificity
Paroxysmal Cold Hemoglobinuria
137
A rare hemolytic anemia caused by anti-P
Paroxysmal Cold Hemoglobinuria
138
Positive sucrose hemolysis and Ham's tests
Paroxysmal Nocturnal Hemoglobinuria
139
Screening test for Paroxysmal Cold Hemoglobinuria
Donath- Landsteiner test
140
It attaches to the RBC at lower temperature, it activates complement at a warmer temperature. It’s a cold reacting IgG autoantibody termed as auto hemolysin
Anti-P
141
It attaches to the RBC at lower temperature, it activates complement at a warmer temperature. It’s a cold reacting IgG autoantibody termed as auto hemolysin
Anti-P
142
This usually happens in soldiers after intense marches
March Anemia
143
These are consumptive coagulopatis that involves deposition of microthrombi and conditions in the blood vessels
Microangiopathic Red Cell Destruction/ Disseminated Intravascular Coagulation
144
Most common human enzyme deficiency in the world; sex linked; highest in young RBCs
G6PD-Dehydrogenase Deficiency
145
Presents with lots of Heinz bodies inclusions
G6PD-Dehydrogenase Deficiency
146
For blacks, G6PD-Dehydrogenase Deficiency is triggered by?
primaquine
147
For non blacks, G6PD-Dehydrogenase Deficiency is triggered by?
ingestion of chloramphenicol, quinine, and quinidine and the legume fava beans (Favism)
148
In G6PD-Dehydrogenase Deficiency, ingestion of this will cause hemolytic crisis
Legume fava beans (Favism)
149
Characterized by increase serum bilirubin and reticulocytes count
G6PD-Dehydrogenase Deficiency
150
In this condition, mature erythrocytes lack mitochondria and are exclusively dependent on anaerobic glycolysis for generation of ATP
Pyruvate Kinase Deficiency
151
Result is a rigid inflexible cells that are sequestered by the spleen
Pyruvate Kinase Deficiency
152
Shown to be resistant to malaria
Pyruvate Kinase Deficiency
153
Auto hemolysis is normal in this condition
Pyruvate Kinase Deficiency
154
In this condition, ferrous iron is converted into ferric iron instead of a normal hemoglobin, methemoglobin is present
Methemoglobin Reductase Deficiency
155
Methemoglobin Reductase Deficiency is also known as?
Hemoglobin M disease
156
A deficiency in this enzyme can result from the inheritance of an autosomal recessive traitor in conjunction with hemoglobin M disease, or as a result of exposure to toxic substances or various drugs
NADH diaphorase or Methemoglobin Reductase Deficiency
157
There is an impaired nucleotide metabolism, accumulation of pyridmidine; impairs degradation of RNA;
Pyrimidine 5 nucleotide deficiency
158
Third most common enzyme deficiency
Glucose phosphate isomerase deficiency
159
In this deficiency, auto hemolysis is increased and is poorly corrected by glucose
Pyrimidine 5 nucleotide deficiency
160
In this deficiency, Auto hemolysis is increase and is partially corrected by glucose
Glucose phosphate isomerase deficiency
161
Heterozygous state for Hb S
Sickle Cell Trait (Hb AS)
162
This is the most common hemoglobinopathy in the United States
Sickle Cell Trait (Hb AS)
163
A benign condition without clinical symptoms or hematologic abnormalities
Sickle Cell Trait (Hb AS)
164
Glutamic acid in the sixth position on the β- chain is replaced by valine
Sickle Cell Disease
165
Confers protection against P. falcifarum
Sickle Cell Trait (Hb AS)
166
Infectious crisis is commonly due to?
streptococcus pneumonia
167
It is freely soluble when fully oxygenated; when O2 is removed, this polymerizes, with formation of tactoids (fluid crystals) that are rigid and deforms the cell into the shape that gave the disease its name
Hb S or Sickle Cell Disease
168
Primary cause of death of sickle cell disease
Infectious crisis
169
The complications involve in infectious crisis are?
- Vaso-occlusive crises - Bone and joint crises - Aplastic crises - No Hb A
170
Common in African Americans
Hemoglobin SC Disease
171
In this disease, Patients have only Hb S and C with an absence of Hb A and normal increased levels of Hb F
Hemoglobin SC Disease
172
Anicytosis and poikilocytosis are mild to severe in?
Hemoglobin SC Disease
173
IDENTIFY: No Hemoglobin A present, microcytic hypochromic and splenomegaly is usually present
Hemoglobin S-Beta Thalassemia
174
Substitution of lysine for glutamic acid (a2 β2- glu --> lys) in the sixth position of the N- terminal end of the beta chain
Hemoglobin C
175
There is a presence of crystalline structures in the red cells that appears as blocks or bars of gold
Hemoglobin C
176
Second most common Hemoglobin variant worldwide
Hemoglobin E
177
Extremely high occurrence in individuals from Southeast Asian countries. It resembles a thalassemia trait; there’s microcytosis, erythrocytosis but normal MCHC & only a slight anemia
Hemoglobin E
178
This constitutes the most common D variant in African Americans
Hb D Los Angeles (Punjab) (B121 glu--> gln)
179
Most common alpha chain variant in black people
Hb G Philadelphia ( a 68asn--> lys)
180
Two major types of Hereditary Persistence of Fetal Hemoglobin
(1) Pancellular and (2) heterocellular (or Swiss) HPFH
181
A hemoglobin analogous to the Lepore hemoglobin, which is associated with HPFH phenotype
Hb Kenya
182
Has less Hb F ranging from 2% to 5%
Heterocellular or Swiss Type HPFH
183
The Hb F is homogeneously or evenly distributed among the red cells
Pancellular HPFH
184
The distribution of HbF is uneven: Both F cells and erythrocytes lacking Hb F are present
Heterocellular or Swiss Type HPFH
185
Diagnosed based on elevated hematocrit level above the normal range
Polycythemia (Erythrocytosis)
186
According to WHO, what is the male and female Hgb range for polycythemia?
> 18.5 g/dL for men > 16.5g/dL for women
187
Increase in the total red cell mass in the body
Absolute Polycythemia
188
The total red cell mass is normal, but the Hct is elevated because the plasma volume is decreased (usually seen in dehydration)
Relative Polycythemia
189
Known as apparent polycythemia or Gaisbock syndrome.
Spurious Polycythemia
190
The red cell mass is often high normal and the plasma volume is low normal
Spurious Polycythemia
191
Characterized by an increase panmyelosis, erythrocytosis, leukocytosis, and thrombocytosis of varing degrees
Polycythemia Vera
192
Where all cell lines are increased
panmyelosis
193
A condition where there is an excessive proliferation of erythrocytes as well as other cells lines
Polycythemia Vera
194
Cite the polycythemias classified under absolute polycythemia
1. Secondary polycythemia with appropriately increased EPO production 2. Secondary polycythemia with inappropriately increased EPO production 3. Genetic polycythemia 4. Primary marrow disorders (Polycythemia vera)
195
Cite the polycythemias classified under relative polycythemia
1. Diminished plasma volume: dehydration; shock 2. Spurious polycythemia (stress polycythemia; Gaisbock syndrome)