Chap 16 Flashcards
RBC Morphology
RBC morphology is examined via?
Wright stained blood smear.
What are the 5 morphological features of RBCs examined?
Size
Color
Shape
Inclusions
Distribution
What 2 morphological features correlate W/ red cell indices?
Size and Color
A normal mature RBC is?
Normochromic-normal color 1/3 of RBC empty
Normocytic- Normal Size 7-8um (MCV=80-100fL)
Discocyte
normal RBC survival of 120 days, depending upon maintaining the RBC shape.
What is the main Hgb type in normal RBCs?
Hgb A
(T or F) Normal RBC morphology is not quantitated?
True
Normocytic RBCs MCV?
82.0-98.0 fL
Normocytic RBCs RDW?
< or = 14.0%
A uniform RBC size would indicate the the RBC population is?
Homogeneous
Anisocytosis
Heterogenous RBC population
Anisocytosis has a high?
RDW >14.0%
Dimorphic RBC Population means?
The RBC population is heterogeneous or is made of 2 different cell populations.
A dimorphic RBC population would cause what RBC indice to be falsely normal?
MCV
Anisocytosis is classified as being w/?
Microcytic or Macrocytic
Normal Color of RBCs is called?
Normochromic
Normochromic MCHC is?
32-36%
Hypochromic
less Hgb coloring the cell, MCHC <32.0%
Poikilocytosis
Abnormal RBC shape, Rigid RBCs.
Spherocyte
No longer biconcave discs, slightly smaller, Hyperchromic, Little to no are of central pallor due to being overfilled w/ Hgb.
Spherocyte MCHC is?
> 36%
Spherocyte MCV is?
Within normal range
Hereditary Spherocytosis
Red cell membrane defect due to deficiency of Spectrin, Ankyrin, or Band 3 protein.
What happens to the membrane of an RBC, in a PT W/ Hereditary Spherocytosis?
The skeletal lipid bilayer is uncoupled, resulting in membrane loss.
Autoimmune Hemolytic Anemia
end result of the coating of RBCs W/ IgG and/or Complement proteins.
Acanthocytes (Spur Cells)
Between 3-12 thorny projections of uneven length along cell membrane.
What is the specific mechanism for the formation of acanthocytes?
Unknown
What is increased in acanthocytes?
Cholesterol to Phospholipid ratio.
What are the possible pathologies of a PT W/ Acanthocytes?
Alcohol Intoxication
Pyruvate Kinase (PK) deficiency
Congenital Abetalipoproteinemia
Vitamin E Deficiency
Post-Splenectomy
Echinocytes (Burr Cell, Crenated Cells)
Sea-urchin cells that can develop as a result of allowing blood to stand for prolonged time.
When a freshly made blood film has the presence of Burr Cells what could it indicate?
Renal Disease
Dehydration as a result of severe gastroenteritis.
In larger #s, are a artifact of sample contamination.
“True” Burr Cells (Echinocytes) occur in small numbers in what pathologies?
Uremia
Heart Disease
Stomach Cancer
Bleeding Peptic Ulcers
PTs W/ untreated Hypothyroidism
Liver Disease
Renal Disease
Burn PTs
When can Burr Cells appear in any situation?
Changes in tonicity of the intravascular fluid (Dehydration).
What separates spherocytes and acanthocytes from Burr cells, in appearance only?
Spherocytes and Acanthocytes have no pallor.
Codocytes (Target Cells)
Bell-shaped, thin-walled cells W/ increased surface area compared to volume.
Pathologies associated W/ Target Cells?
Liver Disease
Thalassemias
Hyposplenism
Some abnormal Hgb (Hgb S)
Drepanocyte (Sickle Cells)
Deoxygenated RBC that becomes a crescent or sickle-shaped.
Which pathology are Sickle cells seen in?
Abnormal Hb S
SCD
Sickle Cell Trait
What causes Hb S?
Replacement of glutamic acid W/ valine @ the 6th position on the Hgb B-chain.
What deforms the RBC?
Precipitation of polymerized Hb S.
Characteristic of SCD is?
Double-Heterozygote disorder
C Crystals?
RBCs contain Hb C
SC Crystals?
RBCs contain Hb S and Hb C
Sickle Cells?
RBCs contain Hb S.
What cell is always present W/ sickle cells?
Target Cells
What is the shape of SC Crystals?
Bizarre
Elliptocytes (Cigars, Ovalocytes)
Oval or cylindrical shaped, biconcave disc.
Both oval and cylindrical shaped elliptocytes, have quantitative and qualitative abnormality of which 2 major membrane proteins?
Skeletal proteins Spectrin and Protein 4.1.
Incidence of Elliptocytes seen in a normal PB smear?
5%
Percentage of Elliptocytes seen in Hereditary Elliptocytosis?
Between 30-100%
What type of anemia are Elliptocytes a feature of?
Iron Deficiency Anemia (IDA)
Dacryocytes (Teardrops)
Single, elongated extremity.
Characteristic feature of which disorders?
Leukoerythroblastic Disorders
(I.E. Myelofibrosis or Metastatic Carcinoma)
Thalassemias
Megaloblastic Anemia
Stomatocytes (The mouth, Stomas)
Bowl-shaped RBCs W/ a slit-like area of pallor.
Stomas are associated W/?
Alcoholism
Hereditary Stomatocytosis
S.E. Asian Ovalocytosis
What is the cause of Hereditary Stomatocytosis?
A membrane deficiency of protein 7.2b or stomatin, resulting in sodium influx into cell and potassium exiting the cell.
The MCV of a PT W/ Hereditary Stomatocytosis is?
High, about 130 fL
(T or F) Stomas can occur as an artifact?
True
Schistocytes (Schistos)
Fragmentation due to a loss of a piece of the cell membrane, may or may not contain Hgb.
Schistocytes include?
Burr Cells
Helmet Cells
Schistos
How many pathways can lead to fragmentation for Schistocytes?
2 pathways
1 Pathway of schistocytes fragmentation?
Alteration of normal fluid in circulation
(Vasculitis, Malignant Hypertension, Heart Valve replacement).
What is the intrinsic pathway of fragmentation in Schistocytes?
Defects of RBCs that make it less deformable (Spherocytes and Antibody-covered RBCs).
Dangocytes (Bite Cells)
Formed when Heinz Bodies (HBs) are removed from cell.
Bite cells are characteristic of what?
Oxidant Hemolysis
What pathologies are bite cells seen it?
G6PD Deficiency
Oxidative Drug use (Dapsone, Salazopyrin, Anti-malarial Drugs)
Keratocytes ( Blister Cell, Helmet Cell)
Appear W/ horns or helmet W/ chin straps.
What pathologies are associated W/ Helmet Cells?
Trauma, especially cellular damage from contact with fibrin strands.
(T or F): RBC inclusion reduce RBC deformity?
True
Basophilic Stippling
Fine, medium, or coarse blue granules W/ uniform distribution w/n the RBC.
Basophilic Stippling represents ribosomal RNA which is precipitated during?
Staining
Conditions/diseases Basophilic Stippling is found in?
Thalassemias
Hemoglobinopathies
Sideroblastic Anemia (SA)
Heavy Metal Poisoning (Lead)
Myelodysplastic Syndrome
Howell-Jolly Bodies (HJBs)
Spherical blue-black inclusions of RBCs seen on a Wright-stained smear.
What are HJBs made of?
Nuclear fragments of condensed DNA (1-2um), that are normally removed by the spleen.
What conditions/diseases do we find HJBs in?
Severe Hemolytic Anemias
PTs W/ dysfunctional spleens
PTs who’ve had a Splenectomy
Megaloblastic Anemia
Thalassemia
Myelodysplastic Syndrome
Hyposplenism
Pappenheimer Bodies (PHBs)
Iron-containing granules in RBCs (Siderotic Granule).
Why are PHBs seen in RBCs?
The iron aggregated W/ the mitochondria and ribosomes.
What is the appearance of PHBs?
Faint violet or magenta specks, often in small clusters.
What conditions/diseases are associated W/ PHBs?
Sideroblastic Anemia
Thalassemias
Hemoglobinopathies
Megaloblastic Anemia
Hyposplenism
Post-Splenectomy
Siderocytes
A mature erythrocyte containing siderotic granules.
Siderotic Granules
Iron-containing granules
To verify RBC inclusions containing Iron, what stain should be used?
Iron stain, such as Prussian Blue.
Heinz Bodies (HBs)
small, round inclusions of denatured Hgb.
HBs are associated W/ what conditions/diseases?
Congenital Hemolytic Anemias, resulting in Hb precipitates (G6PD Deficiency).
Unstable Hgbs
Oxidant drugs/chemicals
Cabot Rings
Thin, Red-violet stained strands.
Cabot Rings shape?
Rings, Figure 8, Shapes of the letter B.
Cabot ring incidence?
Rare
What is the possible cause of Cabot rings?
Microtubules remaining from a mitotic spindle.
Cabot rings are associated W/ what conditions?
Megaloblastic Anemia
Lead poisoning
Disorders of Erythropoiesis
Splenectomy
Myelodysplastic Syndromes
Diffuse Basophilia (Polychromasia)
RNA inclusion of bluish tinge throughout the plasm of an erythrocyte.
What cell is polychromasia commonly seen in?
Retics under supravital stain
Diseases/Conditions associated W/ polychromasia?
Hemolytic Anemia
Treatment of Iron, Vitamin B-12, or Folate deficiency.
Which type of Hb is seen W/ golf ball looking, dispersed, dark blue granules?
Hb H
(T or F): Hb H is visible on Wright’s Stain?
False
What is the composition of the Hb H inclusion?
Precipitated B- globin chains of Hgb.
Polychromasia under Wright’s Stain and Supravital Stain?
Bluish tinge T/O plasm under Wright’s.
Dark blue granules & filaments in the plasm under Supravital.
Basophilic stippling W/ Wright’s and Supravital?
SVS & Wright’s- Dark blue-purple W/ punctate grans T/O plasm.
HJBs under wright’s and SVS?
The same, dark blue-purple, dense, round granules, usually 1 per cell, but can have multiples.
HBs W/ SVS and Wright’s?
SVS- Round, dark blue-purple granule, attached to inner RBC membrane.
Wright’s- Not visible
PHBs on Wright’s and SVS?
The same, irregular clusters, small, light to dark blue granules, near the periphery of cell.
Cabot Rings on SVS and Wright’s?
SVS- Rings or figure 8s
Wright’s- Blue rings or figure 8s
Hb H W/ Wright’s and SVS?
SVS- Fine evenly dispersed dark blue granules, “Golf Ball appearance.
Wright’s- Not visible
