POIKILOCYTOSIS prt. 1 Flashcards
Poikilocytes secondary to DEVELOPMENT ABNORMALITIES
Oval Macrocytes (Microovalocytes)
-Large oval shaped cells with marked increased MCV.
Macroovalocytes
-Occur due to nuclear maturation defect in the early marrow cells caused by Vit B12 or folate deficiency;
strongly suggest MEGALOBLASTIC ANEMIA
Macroovalocytes
Poikilocytes secondary to MEMBRANE ABNORMALITIES
Elliptocytes (Ovalocytes)
Spherocytes
Codocytes
Echinocytes
Burr cells
Acanthocytes
Stomatocytes
These cells result from hereditary or acquired conditions and range from egg-shaped or slightly oval to sausage, rod, or pencil forms
Elliptocytes (Ovalocytes)
With electron microscopy, Hb appears to be concentrated at the two ends of the cell, leaving a normal central area of pallor.
Elliptocytes or ovalocytes
may be acquired in iron deficiency anemia, megalo-blastic anemia, and myelophthisic anemia, in which as many as_____ of the cells may be oval.
Elliptocytes or ovalocytes
10%
Megaloblastic anemia is characterized by oval macrocytes, which may be____ um or more in diameter and lack central pallor.
These are also observed in thalassemia and sickle cell anemia.
9
Elliptocytes
The principal defect is considered to be in the cytoskeleton, with a decrease in the skeletal membrane protein band 4.1.
An increased heat sensitivity of spectrin in some families with hereditary______ has been reported.
elliptocytosis
The life span of______ may be somewhat shortened in a few individuals; however, they usually function normally.
The osmotic fragility is normal.
elliptocytes
Spherocytes may be caused by a hereditary or an acquired condition. Several molecular defects in membrane proteins have been identified in hereditary spherocytosis;_______ deficiency has been found in many patients
spectrin
are not easily deformed and therefore may lose their membrane by fragmentation during passage through the circulation.
These cells become smaller and denser with increased Hb content and become less deformable with age.
Spherocytes
When the cell is deprived of membrane as it ages, it assumes the spherical shape.
______have a shortened survival time because they are sequestered in the spleen and hemolyzed.
Spherocytes
The hallmark of ___________ is a spherocyte that is fairly uniform in size and density with a decreased membrane surface:volume ratio.
hereditary spherocytosis
show increased fragility when placed in increasing dilutions of hypotonic saline in the osmotic fragility test
Spherocytes
After splenectomy in patients with_________, hemolysis decreases but they still persist, indicating that the abnormality involves the red cell membrane itself rather than splenic damage to the cells.
hereditary spherocytosis
Frequent causes of_______ are immu-nohemolytic anemia secondary to autoimmune or isoim-mune antibodies, Heinz body hemolytic anemia, microan-giopathic hemolytic anemia, and hemolysis secondary to water dilution.”
acquired spherocytosis
Banked blood stored for long periods of time develops_______.
spherocytes
have a central area of Hb surrounded by a relatively colorless ring and a peripheral ring of Hb
Codocytes or target cells
By scanning electron microscopy the cell has a bell or tall hat shape and appears to be thin walled and concave.
Codocytes or target cells
A codocyte (Greek kodon, “____”) is also called a _____cell. This shape is always acquired.
bell
Mexican hat
appear when the membrane surface is increased after loading of the membrane with cholesterol and phospholipids.
In other words, the cell is similar to a bag too large for its contents.
Its greater osmotic resistance (or decrease in osmotic fragility) is explained by the increase in surface to volume ratio.
Codocytes
appear when the membrane surface is increased after loading of the membrane with cholesterol and phospholipids.
In other words, the cell is similar to a bag too large for its contents.
Its greater osmotic resistance (or decrease in osmotic fragility) is explained by the increase in surface to volume ratio.
Codocytes
Finding target cells in only one portion of the film suggests an_____ of film preparation.
Fixing blood films in_____ before staining may help avoid this problem.
artifact
methanol
are characteristic of thalassemia; hemoglobinopathies SS, CC, DD, EE, and S-thalassemia; obstructive liver disease; postsplenectomy state; and iron deficiency anemia
Codocytes
Echinocytes (from the Greek echinos, “_________”) have evenly distributed, uniform-size blunt spicules or bumps on their surfaces
sea urchin
______ or ______ red cells may be seen on films made from anticoagulated blood that is several hours old but such cells are artifacts not normally present in vivo.
Echinocytes or crenated
crenation is caused by release of basic substances from glass slides that change the pH and transform the cells into_______.
In stored blood, the cells may be numerous because of depletion of ATP and biochemical abnormalities in plasma.
The cells formed in vitro can be reversed to normal shape, whereas those formed in vivo cannot.
echinocytes
Transformation of discocytes to_____ can be observed on a glass slide using a moist saline preparation of red cells in the presence of an elevated (basic) pH
echinocytes
red cells acquire a membrane abnormality with irregularly sized and unevenly spaced spicules. Such red cells are called_______
burr cells
The number of______ often increases as blood urea nitrogen (BUN) increases.
This membrane alteration is probably related to plasma chemical abnormalities.
burr cells
The differences between crenated cells (echinocytes) and burr cells may be minimal and not always recogniz-able.
________with uniform blunt spicules represent an artifact that is evident in practically every cell in the thin portion of the film and SHOULD NOT BE REPORTED
In contrast,______ may be distinguished by their irregularly sized spicules and variable number in different microscopic fields and should be reported.
A burr cell has also been called an______ by several hematologists because of its membrane irregularities.
Crenated cells
burr cells
echinocyte
Acanthocytes (from the Greek word acantho,______ or ______)
“thorn” or “spike”
_______are small, densely stained red cells that are no longer disc shaped and have a few irregularly spaced pointed spicules or thornlike projections of various lengths and widths over their surfaces
Acanthocytes
The spicules may appear clublike.
Acanthocytes
may be acquired or inherited and are smaller than normal red cells because they are becoming spheroidal.
Generally they have fewer, more irregular, and more blunted points than burr cells.
Acanthocytes
Unlike burr cells,______ cannot be induced to regain a normal shape.
These cells may be caused by changes in the ratio of plasma lipids (lecithins and sphingomyelins).
acanthocytes
_______ have been observed in alcoholic cirrhosis with hemolytic anemia, malabsorption states, postsplenectomy states, hepatitis of newborns, pyruvate kinase deficiency, and disorders of lipid metabolism
Acanthocytes
Increased numbers of acanthocytes have been reported in a rare congenital syndrome called_________, which is characterized by mild hemolytic anemia, retinal degeneration, and steatorrhea.
abetalipoproteinemia
______ on a fixed and stained film have an elongated or slitlike area of central pallor instead of the usual circular form.
Stomatocytyes
______ on a fixed and stained film have an elongated or slitlike area of central pallor instead of the usual circular form.
Stomatocytyes
are so named for their mouth-shaped central pallor.
These cells appear bowl shaped in a moist preparation and by stereoscan microscope.
Stomatocytes
are so named for their mouth-shaped central pallor.
These cells appear bowl shaped in a moist preparation and by stereoscan microscope.
Stomatocytes
Blood films from normal individuals may demonstrate a few_______, but these cells are usually observed in patients with alcoholism, cirrhosis, obstructive liver disease,” and Rh null disease.
These cells also may occur as artifacts of blood film preparation.
stomatocytes
One of the suggested consequences involves a membrane defect that results in high cellular sodium and low potassium content
The heterogeneous clinical picture
results from an abnormal sodium to potassium transport ratio and a greatly increased rate of active cation trans-port.
Because of the shape of the red cell and the somewhat impaired deformability, ________ may be retained in the spleen.
stomatocytes
