Chapter 5 - RED BLOOD CELL STUDIES Flashcards
Characteristics of a normal Red Blood Cell:
• 7 to 8 um in diameter:
• Average volume:
• Average surface area:
• Shape and Deformity:
• Cytoplasm:
• Average life span:
1.5 to 2.5 um in thickness
90 fL
160 um2
Discocyte/Discocyte; Flexible & deformable
uniformly pink without inclusions
120 days
: used to measure the effective survival of RBCs in vivo.
Chromium-51 (51Cr)
51Cr half-survival time range is
28 - 38 days.
RBC Membrane Compositions:
- Proteins (50%)
- Lipids (40%)
- Carbohydrate (10%)
: Underlie the lipid layer and regulate membrane shape & deformability
RBC Membrane
• Integral proteins:
Glycophorin A and component a (band 3)
• Peripheral proteins:
Spectrin and Actin (form the cytoskeleton)
• Phospholipids:
External surface:
Internal surface:
phosphatidyl choline, glycolipids & sphingomyelin
Cephalin, phosphatidylinositol & phosphatidy|serine
: Amount depends upon the concentration of plasma cholesterol, bile acids, and the activityof the enzyme LCAT.
Cholesterol
• Some serve as red cell antigens (e.g. ABH antigen)
- Carbohydrate (10%)
Anaerobic glycolysi s
Embden Meyerhof Pathway
Major source of 2. red cells ATP
Embden Meyerhof Pathway
oxidative glycolysis
Hexose Monophosphate Shunt/Pentose Phosphate Shunt
generates NADPH and reduced glutathione in the presence of Glucose 6-PO4 dehydrogenase (G6PD). GSH protects the hemoglobin from oxidation by peroxides.
Shunt/Pentose Phosphate Shunt
Generates 2,3DPG /2,3BPG
RapoportLuebering Shunt
Reduction of methemoglobin by NADPH is more efficient in the presence of methemoglobin reductase (cytochrome b5 reductase) which serves as an intermediate electron carrier.
Methemoglobin Reductase Pathway
As RBC ages, there is a decrease in its (?) and an increase in (?). This natural deterioration leads to its phagocytosis.
enzymes, ATP and size
density
destruction of senescent red cells by splenic macrophages.
Extravascular (Macrophage-mediated)
Hemoglobin undergoes degradation within the macrophage where iron is stored as ferritin, amino acids of globin are returned to the metabolic amino acid pool and protoporphyrin is converted to bilirubin which is released into the plasma and excreted by the liver in bile.
Extravascular (Macrophage-mediated)
may be caused by the turbulent environment in the circulation
Intravascular destruction (Mechanical hemolysis)
Hemoglobin is released into the plasma and can be filtered by the kidneys.
Intravascular destruction (Mechanical hemolysis)
Plasma (?) salvage the released hemoglobin so that its iron is not lost in the urine
haptoglobin and hemopexin
Biconcave disc
Normal
Normocyte
Smaller RBCs, with diameter less than 7 µm
Microcyte
Any defect that results in impaired Hb synthesis
Microcyte
Hypochromic
Anulocyte
Iron deficiency anemia;
Microcyte
Hypochromic/Anulocyte
Ellipto
Sideroblastic anemia
Microcyte
Pappenheimer
Thalassemia
Microcyte
Hypochromic/Anulo
Ellipto
Target
BS
PP
Anemia of Chronic Inflammation
Microcyte
Lead Poisoning
Microcyte
BS
CR
RBCs >9 µm in diameter, with an MCV >100 fL
Macrocyte
larger than 10 µmn diameter
Gigantocyte/ Megalocyte
-Accelerated erythropoiesis
Macrocyte
Gigantocyte/ Megalocyte
HJ
BS
- Defective DNA synthesis
Macrocyte
Gigantocyte/ Megalocyte
-In conditions where membrane cholesterol and lecithin levels are increased
Macrocyte
Gigantocyte/ Megalocyte
Hemolytic anemia & Acute Blood Loss
Macrocyte
Gigantocyte/ Megalocyte
Megaloblastic Process; Chemotherapy
Macrocyte
Gigantocyte/ Megalocyte
Liver disease, Alcoholism
Macrocyte
Gigantocyte/ Megalocyte
Presence of 2 distinct populations of red cells that may differ in size, shape or hemoglobin content
Dimorphic RBCs
anemia after transfusion
Dimorphic RBCs
ANISOCYTOSIS & POIKILOCYTOSIS GRADING
Normal
Slight
1+
2+
3+
4+
5%
5 10%
10 25%
25 50%
50 75%
> 75%
MACROCYTOSIS GRADING
1+ (slight)
2+ to 3+ (moderate)
4+ (marked)
25%
25% - 50%
> 50%
Homogenous with central palor
Normal
Normochromic
RBCs show inc central pallor (exceeds 1/3 of the diameter of the red cell
Hypochromic
Thin & poorly hemoglobinized cells
Anulocyte
defect in hb synthesis due either to:
decrease in heme synthesis
defect in globin chain synthesis
Iron Deficiency Anemia (IDA)
Thalassemia
Hypochromic
Anulocyte
Cells that lack central pallor and with reduced diameter
Spherocytic (Hyperchromic)
Defects in the cytoskeletal proteins
Spherocytic (Hyperchromic)
Hereditary and acquired spherocytosis
Spherocytic (Hyperchromic)
Area of central pallor is one-half of cell diameter
1+
Area of pallor is two-thirds of cell diameter
2+
Area of pallor is three-quarters
3+
Thin rim of hemoglobin
4+
: 1/3 to 2/3 of cells diameter
1+ (slight) central pallor
: more than 2/3
2+ to 3+ (moderate)
: thin rim on the periphery
4+ (marked)
Percentage of Polychromatophilic Cells
Slight
1+
2+
3+
4+
1 %
3 %
5 %
10 %
>11 %
PcC/f
1+
2+
3+
( 1 3 polychromatophilic cells/field)
( 3 5 PcC/f)
( >5 PcC/f )
Range from egg-shape, slightly oval to sausage, rod, or pencil forms
Ovalocytes (Elliptocytes)
Hb appears to be concentrated at the two ends of the cell, leaving a normal central pallor area.
Ovalocytes (Elliptocytes)
decrease in skeletal membrane CHON band 4.1
Ovalocytes (Elliptocytes)
increase heat sensitivity of spectrin
Ovalocytes (Elliptocytes)
Hereditary elliptocytosis
Ovalocytes (Elliptocytes)
Small numbers may by acquired in:
- iron deficiency,
- megaloblastic anemia,
- myelophthisic anemia,
- thalassemias & sickle cell anemia
Ovalocytes (Elliptocytes)
Smaller in diameter than normal RBC
Spherocyte
With concentrated hb content
Spherocyte
No visible central pallor
Spherocyte
indicates a hemolytic process (hemolysis results from a membrane abnormality
Spherocyte
Hereditary Spherocytosis
Spherocyte
Autoimmune hemolytic anemia
Spherocyte
Agglutination
Normal aging process
Spherocyte
Storage phenomenon
Spherocyte
Severe burns
Spherocyte
With irregularly sized & unevenly spaced spicules
Burr cell
Depletion of ATP
Burr cell
Exposure to hypertonic solution
Burr cell
May occur in situations that cause a change in tonicity of the intravascular fluid
Burr cell
Associated w/ renal insufficiency
Burr cell
What is the difference between a burr cell and an echinocyte?
With few (3-12) irregularly spaced, pointed spicules/thornlike projections of various lengths and widths
Acanthocytes
May be caused by changes in the ratio of plasma lipids
Acanthocytes
Associated w/ end stage liver disease
Acanthocytes
Alcoholic cirrhosis
Acanthocytes
PK deficiency
Acanthocytes
Congenital abetalipoproteinemia
Acanthocytes
Post-spenectomy
Acanthocytes
Target
Pappenheimer
Cabot rings
Normal sized cell with an elongated or a slitlike mouth or stoma
Stomatocytes (Mouth cells)
cup-shaped
Stomatocytes (Mouth cells)
Membrane defect that results in high cellular sodium and low potassium content
Stomatocytes (Mouth cells)
Hereditary stomatocytosis
Stomatocytes (Mouth cells)
Rh null disease
Stomatocytes (Mouth cells)
Obstructive liver disease
Stomatocytes (Mouth cells)
Alcohol excess
Stomatocytes (Mouth cells)
myelodysplastic syndromes
Stomatocytes (Mouth cells)
hydroxyurea therapy
Stomatocytes (Mouth cells)
Hereditary stomatocytosis
Stomatocytes (Mouth cells)
With a central area or hb surrounded by a colorless ring and a peripheral ring of hb
Target Cells (Codocytes)
bell-shaped or tall hat shaped
Target Cells (Codocytes)
Increase in cholesterol & phospholipids.
Target Cells (Codocytes)
Excess surface area to volume ratio
Target Cells (Codocytes)
Hemoglobinopathies
Target Cells (Codocytes)
Heinz
PH
BS
Thalassemia
Micro, Hypo/Anulo
Ellipto, Target Cells (Codocytes)
BS, PP
Post-splenectomy
Target Cells (Codocytes)
Acanthocytes
Pappenheimer
Cabot
Poikilocytes Secondary to TRAUMA
Two pathways of fragmentation are recognized:
Alteration of normal fluid circulation (DIC, TTP, MAHA) Intrinsic defects of the red cell (spherocytes, antibody altered red cells, inclusions)
Schistocytes (Schizocytes)
Fragments of RBCs varying in shapes
Helmet cells
Triangular cells
keratocytes
Schistocytes (Schizocytes) fragmentation due to:
- Exposure of cells to abnormal conditions
- Contact with fibrin strands or damaged endothelium.
- Intrinsic defects of RBCs
Hemolytic anemias
Schistocytes (Schizocytes)
Keratocytes, Bite Cells, Degmacytes
erythrocytes with a pair of spicules or ‘horns’ surrounding a gap in the cell outline.
Keratocytes, Bite Cells, Degmacytes
Results from removal of a Heinz body from a cell by splenic macrophages; or when an erythrocyte is caught on a fibrin strand.
Keratocytes, Bite Cells, Degmacytes
G6PD deficiency
Keratocytes, Bite Cells, Degmacytes
Heinz
Half-moon/ crescent cells; large pale- pink staining ghost of the RBC
Semilunar bodies
Frequently observed in malaria and in other conditions causing overt hemolysis
Semilunar bodies
Overt hemolysis
Semilunar bodies
Pear-shaped with a single elongated point
Teardrop Cells (Dacrocytes)
Cuased by squeezing & fragmentation during splenic passage
Teardrop Cells (Dacrocytes)
Myelofibrosis
Teardrop Cells (Dacrocytes)
Presence of inclusion bodies
Teardrop Cells (Dacrocytes)
Myelophthisic anemia
Ellipto
Teardrop Cells (Dacrocytes)
Pernicious anemia
Teardrop Cells (Dacrocytes)
B-thalassemia
Teardrop Cells (Dacrocytes)
Smaller than spherocytes
Microspherocytes & Pyropoikilocyte
Also lack central
Microspherocytes & Pyropoikilocyte
Results from repeated fragmentation of red cells & from thermal damage to cell membrane
Microspherocytes & Pyropoikilocyte
Severe burns
Spherocyte
Microspherocytes & Pyropoikilocyte
Hereditary pyropoikilocytosis
Microspherocytes & Pyropoikilocyte
Other appearances related with hemolysis
Blister cell
with thinned portion
Blister cell
- appear like pinched bottle
Knizocytes
- distorted red cells
Pyknocytes
Thin and elongated with pointed ends.
Drepanocytes/Sickle cells
Polymerization of hemoglobin
Drepanocytes/Sickle cells
Sickle cell anemia
Ellipto
Drepanocytes/Sickle cells
With one or more fingerlike, blunt-pointed projections that protrude from the cell membrane leaving a pale area at the opposite end
Hb SC crystal
Hexagonal; Both ends are blunt
Hb CC crystal
Formed within the membrane
Hb CC crystal
Helmet cells Grading
1+ = 1 to 5/field
2+ = 6 to 10/field
3+ = >10/field
Teardrop RBC Grading
1+ = 1 to 5/field
2+ = 6 to 10/field
3+ = >10/field
Acanthocytes Grading
1+ = 1 to 5/field
2+ = 6 to 10/field
3+ = >10/field
Schistocytes Grading
1+ = 1 to 5/field
2+ = 6 to 10/field
3+ = >10/field
Spherocytes Grading
1+ = 1 to 5/field
2+ = 6 to 10/field
3+ = >10/field
Ovalocytes Grading
1+ = 3 to 10/field
2+ = 11 to 20/field
3+ = >20/field
Elliptocytes Grading
1+ = 3 to 10/field
2+ = 11 to 20/field
3+ = >20/field
Burr cells Grading
1+ = 3 to 10/field
2+ = 11 to 20/field
3+ = >20/field
Bizarre-shaped RBC Grading
1+ = 3 to 10/field
2+ = 11 to 20/field
3+ = >20/field
Target cells Grading
1+ = 3 to 10/field
2+ = 11 to 20/field
3+ = >20/field
Stomatocytes Grading
1+ = 3 to 10/field
2+ = 11 to 20/field
3+ = >20/field
Sickle cells Grading
Grade as positive only
Pappenheimer bodies Grading
Grade as positive only
Howell-Jolly bodies Grading
Grade as positive only
Basophilic stippling Grading
Grade as positive only
Large (1 to 3 um), single or multiple small, round, oval or serrated, purplish inclusions on RBC periphery (distorts the membrane)
Heinz Bodies
Results from precipitation of hemoglobin
Heinz Bodies
G-6-PDH deficiency anemia
Heinz Bodies
Kerato
Red cell injury due to chemical insult or under oxidant stress
Heinz Bodies
hemoglobinopathies and thalassemia major
Heinz Bodies
Unstable hemoglobin syndromes
Heinz Bodies
Small greenish-blue inclusion bodies
Hb H Inclusions
Precipitation of hb H
Hb H Inclusions
Seen in Hb H disease
Hb H Inclusions
Small, coarse round granules
Howell-Jolly Body
deep blue or red-purple
Howell-Jolly Body
appears singly & is eccentrically located.
Howell-Jolly Body
Nuclear remnants
Howell-Jolly Body
What is meant by karyorrhexis
+ with Feulgen & Methyl Green Pyronin stains
Howell-Jolly Body
accelerated or abnormal erythropoiesis
Howell-Jolly Body*
Macro/giganto/megalo
BS
megaloblastic anemia
Howell-Jolly Body
BS
Cabot
Ellipto
small (2-3 um) faint blue coccoid bodies that aggregate in small clusters at the periphery of the cell.
Pappenheimer Bodies Siderotic granules
Unused Iron deposits
Pappenheimer Bodies Siderotic granules
- Sometimes may appear as Ringed sideroblast
Pappenheimer Bodies Siderotic granules
sideroblastic anemia
Pappenheimer Bodies Siderotic granules
Micro
Dimorphic
Thalassemias
Ellipto
Target
Pappenheimer Bodies Siderotic granules
BS
hemoglobinopathies
Pappenheimer Bodies Siderotic granules
Target
Heinz
BS
Alcoholism
Pappenheimer Bodies Siderotic granules
Macro/ G/ M
Post-splenectomy
Acantho
Target
Pappenheimer Bodies Siderotic granules
BS
Dark blue granules, uniform and evenly distributed
Basophilic Stippling
Coarse: much more outlined and easily distinguished
Basophilic Stippling
Punctate: coalescing into smaller forms
Basophilic Stippling
Aggregates of ribosomes and mitochondrial remnants
Basophilic Stippling
defective or accelerated heme synthesis, (lead or other heavy metal poisoning, thalassemia & hemoglobinopathies; Megaloblastic anemia)
Basophilic Stippling
Pyramidine-5-nucleotidase deficiency
Basophilic Stippling
Diffuse
Basophilic Stippling
Clumping of RBCs
Agglutination
Presence of antibodies
Agglutination
Cold agglutinin
Agglutination
Autoimmune Hemolytic Anemia
Agglutination
Sphero
Linear alignment of RBCs appearing as stack of coins
Rouleaux
Increased concentration of globulin
Rouleaux
Multiple myeloma
Rouleaux
Waldenstroms macroglobulinemia
Rouleaux
Rouleaux Grading
1+= aggregates of 3 to 4 RBCs
2+ = 5 to 10 RBCs
3+= numerous aggregates with only few free RBCs
Slight
Moderate
Marked
1-2 Slight
3-4 Moderate
≥5
Marked
Basophilic stipplig Grading
1 stippled RBC every other field
1-2
3 or more
iron deficiency during therapy
Dimorphic RBC
combined Vit. B12 /folate and iron deficiency
Dimorphic RBC
decrease in heme synthesis
Hypochromic
Anulocyte
defect in globin chain synthesis
Hypochromic
Anulocyte
Variation Red Cell Size
Normocyte
Microcyte
Macrocyte
Gigantocyte/ Megalocyte
Dimorphic RBCs
Variation in Hemoglobin Distribution
Normochromic
Hypochromic/Anulocyte
Spherocytic (Hyperchromic)
Polychromasia (Reticulocytes)
Poikilocytes Secondary to MEMBRANE ABNORMALITIES
Ovalocytes (Elliptocytes
Spherocyte
Burr cell
Acanthocytes
Stomatocytes (Mouth cells)
Target Cells (Codocytes)
Poikilocytes Secondary to TRAUMA
Schistocytes (Schizocytes)
Keratocytes, Bite Cells, Degmacytes
Semilunar bodies
Teardrop Cells (Dacrocytes)
Microspherocytes & Pyropoikilocyte
Other appearances related with hemolysis:
Blister cell
Knizocytes
Pyknocytes
Poikilocytes & Crystals Secondary to Abnormal Hemoglobin Content
Drepanocytes/Sickle cells
Hb SC crystal
Hb CC crystal
Abnormal Hemoglobin Precipitation
Heinz Bodies
Hb H Inclusions
Abnormal Red Cell Distribution
Agglutination
Rouleaux
Developmental Inclusions
Howell-Jolly Body
Pappenheimer Bodies Siderotic granules
Basophilic Stippling
Cabot Rings