lecture 5-6 Flashcards
how does a mature RBC look like?
- RBC has a biconcave disc shape
- thickness at the periphery is 1 1⁄2 times the center
- this shape allows it to have a greater surface area for gas exchange
- has a diameter of around 7-7.5 u
- saturated with Hb
- normal RBC cannot contain more Hb than it has
- RBC appears dark at the edges and lighter in
the center - light area in the center is called central pallor
why are the edges of an RBC dark in color?
due to the presence of hemoglobin
The biconcave disc shape of an RBC helps it in what function?
gas exchange
normochromic is when the RBC has a normal size (T/F)
false
normocytic
normal sized RBCs are known as:
normocytic
normal Hb content in an RBC is known as:
normochromic
what is anisocytosis?
variation in the size of RBC(s)
when there is minimal variation in the size of RBCs it is referred to as anisocytosis (T/F)
false, significant variation
normally there is minimal variation in size of RBCs (not anisocytosis)
in what diseases do we find anisocytosis?
- present in erythroid disorders/ erythropoetic diseases (altered red cell production)
- in all anemias
it is not characterisitic of any disease
what is microcytosis? MCV=?
- RBC size smaller than normal
- MCV < 80fl
microcytosis is found in what type of diseases?
- fe deficiency anemia
- thalassemia
- hereditary sideroblastic anemia
what is sideroblastic anemia?
- lack of RBCs
- abnormal utilization of iron during erythropoesis
what is macrocytosis? MCV=?
- RBC larger than normal
- MCV > 100fl
macrocytosis is encountered in what type of conditions?
- megaloblastic anemia
- newborn babies
- active erythropoeisis
- liver diseases (chronic) alcoholism
what are hypochromic RBCs? what happens to its central pallor?
- Hb content lower than normal
- central pallor becomes larger
hypochromic anemia is found in what type of diseases?
- fe deficiency anemia
- thalassemia
- hereditary sideroblastic anemia
what cells have no central pallor?
- spherocytes (RBCs smaller than normal)
- polychromatophilic RBCs (RBCs larger than normal)
what is polychromatophilic RBC? what color is it and why?
- early or immature non-nucleated RBCs with ribosomes and RNA
- color is slightly bluish (due to the presence of RNA which is acidic and takes up methylene blue)
stained with a regular romanowsky stain
wright stain fixates cells since it contains alcohol (T/F)
true
brilliant cresyl blue is a potent reducing agent (T/F)
false, oxidizing
wright stain gives ____ color while brilliant cresyl blue gives a ____ color
- diffuse grayish-blue color
- deep blue color
polychromatic cells are fixated or not? and what stain do we use?
reticulocytes are fixated cells or not? and what stain do we use?
polychromasia will not be detected unless reticulocyte count is above __%
above 2%
what is polychromasia? and why does it happen?
- a disorder where we have an abnormally high nb of immature RBCs
- RBCs are prematurely released from the bone marrow during blood formation
polychromatic cells = reticulocytes = ?
stippled RBCs
what are basophilic stipplings? and in what disease do we find them?
(include its color, stain, location….)
- inclusions of aggregated damaged ribosomes (pathologic precipitation of ribosomes)
- fine or coarse deep blue to purple staining
- stained with wright and giemsa
- appears in immature RBCs
- found in chronic hemolytic anemias
- implicated in cases of lead poisoning (heavy metal toxicities)
what is poikilocytosis?
presence of abnormally shaped RBCs
what are some examples of poikilocytosis?
- ovalocytes, elliptocytes, cigar shaped RBCs
- stomatocytes
- tear drop cells (pear-shaped)
- sickle cells
what are the most common abnormal RBC shapes?
ovalocytes, elliptocytes, cigar-shaped RBCs
ovalocytes, elliptocyte, cigar-shaped RBCs are associated with what type of diseases?
- fe deficiency anemia
- thalassemia
- megaloblastic anemia
these cells may be normally present in small numbers
what is megaloblastic anemia?
- is a form of macrocytic anemia
- happens when your BM produces stem cells that make abnormally large RBCs
megaloblastic anemia is a type of __anemia
vitamin deficiency anemia
happens when u dont have enough vitamin b12 and/or vitamin B9 (folate)
what makes the cigar-shaped RBCs slightly different from ovalocytes and elliptocytes?
they are a bit longer and thinner
what do we call the condition when the majority of RBCs are ovalocytes, elliptocytes, or cigar shaped RBCs?
what %?
congenital ovalocytosis or elliptocytosis
95%
Congenital ovalocytosis and elliptocytosis conditions are inherited. what is the type of gene?
autosomal dominant gene
in congenital elliptocytosis there are 2 cases, what are they?
- 95% of the cases are benign and have no disease + these cells function normally
- 5% of the cases show a condition of hemolytic anemia
what makes a stomatocyte an abnormal cell?
its abnormal shape characteristic
it has an elongated (mouth-like) central pallor
__% of RBCs may be stomatocytes in a normal smear
3%
what do we call the condition where we have an increased number of stomatocytes?
congenital stomatocytosis
what are the 2 cases of congenital stomatocytosis?
- 95% of the cases are harmless
- 5% have hemolytic anemia
in what conditions do we see stomatocytes?
diseases, etc..
- liver disease (cirrhosis)
- alcoholism
- artifact of preparation
what abnormal RBC shape could be considered as an artifact of preparation?
stomatocytes
1) tear-drop cells may be encountered in what type of conditions? 2) and if they are very numerous?
- in variety of anemias
- myelofibrosis
what is myelofibrosis?
BM becomes full of fibrous tissue
what characteristics to sickle cells have?
(shape)
- deformed RBCs
- shape of a sickle or cresent
what conditions are sickle cells associated with?
- HbS (sickle hemoglobin)
- sickle cell anemia
what makes crenated RBCs abnormal?
(shape/ structures…etc)
they have blunt spicules evenly distributed over the surface of an RBC
what is the cause of crenated RBCs?
faulty drying of the blood smear
what are the characteristics of acanthocytes?
(shape and others..)
- have irregularly spaced projections (5 finger-like projections/ distortions)
- have decreased survival time
acanthocytes are found in a condition known as:
acanthocytosis or abetaliproteinemia
absence of beta lipoprotein from RBC membrane
what conditions (associated with abnormally shaped RBCs) are inherited?
- congenital elliptocytosis
- acanthocytosis
- spherocytosis
acanthocytosis and spherocytosis could be acquired as well
acanthocytosis could be associated with a number of acquired conditions, what are they?
- alcoholic cirrhosis
- malabsorption states
what are the characteristics of spurr and burr cells?
- uniformly spaced, pointed projections
- smaller
- more numerous (6-10)
what is another name for spurr and burr cells?
echinocytes
echinocytes are characteristic of which type of disease?
- liver disease
- kidney failure
what types of abnormal cells are associated with liver disease?
- stomatocytes
- acanthocytes (alcoholic cirrhosis)
- echinocytes
- target cells (increased surface area associated with free cholesterol)
why echinocytes must be differentiated from crenated RBCs?
since echnocytes and crenated RBCs look similar in shape however echinocytes are associated with liver disease & kidney failure while crenated RBCs are due to an error in drying the smear
what are schistocytes?
fragmented RBCs
what conditions are schistocytes associated with?
- hemolytic anemia (especially intravascular hemolytic anemia)
- ineffective erythropoeisis (destruction of RBCs in the BM or blood vessels)
contain fibrin threads
what special appearance do schistocytes have that help in diagnosis?
triangular or helmet-like appearance
in schistocytes, hemolytic anemia occurs secondary to :______
intravascular coagulation
how cells become target cells?
- when you decrease the volume, leaving surface area constant
- when you increase surface area, leaving volume constant
* RBC membrane will undergo folding/ have wrinkles
–> will look like a target
if you increase the internal volume of the cell, the RBC membrane will undergo folding (T/F)
false, decrease
what condition causes the cell to wrinkle?
(decrease in volume)
any condition which removes Hb
what diseases are associated with target cells?
(RBCs with decreased volume only)
add specific examples of each
- anemias due to decrease in heme synthesis (fe-deficiency anemia)
- anemias due to decrease in globin synthesis (hemoglobinopathies: thalassemia or sickle cell anemia)
what are 2 examples of hemoglobinopathies?
- thalassemia
- sickle cell anemia
how do free cholesterol lead to the formation of target cells?
- RBC membrane is rich in free cholesterol
- this cholesterol exchanges freely with the
free cholesterol in plasma - higher the free cholesterol in plasma => the more cholesterol is taken up by the RBC membrane => the bigger is the membrane => the RBC becomes a target cell
- Free cholesterol in the body is taken up by the liver
- in the liver, it is esterified
- liver would excrete esterified cholesterol
- In severe liver disease, the esterification of cholesterol is depressed
- free cholesterol in the blood increases formation of target cells
what are spherocytes?
- small RBCs
- have no central pallor
- appear darker in color
what are spherocytes associated with?
- spherocytosis (in association with ABO or Rh incompatibility)
- hemolysis due to rigidity of the membrane
what is diserythropoeisis?
abnormality in nuclear membrane resulting in bilobed or multilobed erythroblasts
what is a dimorphic picture/appearance?
- heterogeniety in the size of RBCs
- 2 distinct populations
where can we find dimorphic picture?
- in partially treated fe deficiency
- mixed deficiency anemias (folate/B12 and iron together)
- following red cell transfusion
- sideroblastic anemia
what are rouleaux? and how are they formed?
- stacked/clumped groups of RBCs
- presence of high levels of circulating acute-phase proteins which increase red cell stickiness
what does the presence of rouleaux indicate?
indicator that the patient has high ESR
(infections, autoimmune conditions, chronic inflammation, myeloma)
what are howell-jolly bodies?
round, purple staining nuclear fragments
in what condition do Howell-jolly bodies appear?
(include diseases)
- when we have chromosomal breakage
- spleen is not present or its function is impaired
- some hemolytic anemias (thalassemia)
- megaloblastic anemia
what is the relation between howell-jolly bodies and the spleen?
- RBC passes through the spleen
- spleen removes the HJB
- RBC pass out without it
if we see HJB in peripheral blood => spleen not present/ impaired
what are cabot rings?
- purple staining
- threadlike filaments
- shape of a ring or figure of (8)
- nuclear remnants
- derived from the microtubules of the mitotic spindle
cabot rings are seen in what conditions?
- thalassemia
- megaloblastic anemia
- disturbed erythropoiesis
what type of inclusion is derived from microtubules of the mitotic spindle?
cabot rings
what rbc inclusions are seen in similar conditions?
- howell-jolly bodies
- cabot rings
what are HbC crystals?
(include its color)
- elongated crystals
- blunt ends
- darkly stained in color
what conditions are HbC crystals associated with?
hemoglobin C HbC disease
what is HbC disease?
- blood disorder
- develops bcz RBCs do not contain enough water & are too rigid
- break down earlier than they should leading to mild anemia
what are pappenheimer bodies?
(location inside the cell, color, stain, content…)
- small, irregular, dark staining granules
- near the periphery of an RBC
- stained with wright and giemsa
- stain positively for perls’ prussian blue stain (for iron) –> iron content
normally, no more than 3 iron particles are noted in developing RBCs
what is another name for siderotic granules?
pappenheimer bodies
in what condition do siderotic granules appear?
- sideroblastic anemia
- refractory anemias
- spleen not present
- severe disturbance of Hb synthesis (pathologic sideroblasts are present in BM)
what is the relation between peppenheimer bodies and the spleen?
- spleen normally removes these inclusions (without destroying the cells)
- after splenectomy, they are visible on blood film
what inclusions are associated with the spleen?
- howell-jolly bodies
- pappenheimer bodies
an erythrocyte positive for siderotic iron granules in a prussian blue stain is known as:
siderocyte
a normoblast positive for siderotic iron granules in a prussian blue stain is known as:
sideroblast
what inclusions are stained with wright and giemsa?
- basophilic stippling
- pappenheimer bodies
what are heinz bodies?
(include stains)
- clumps of denatured Hb
- stained with supravital stain
- in romanowsky stain, appears as a pale focal area within the RBC
what are heinz bodies also known as?
bite cells
shaklon mtl kedshin l RBCs
what is peripheral hemoglobinization? what inclusion is it associated with?
- associated with heinz bodies
- they are pale focal areas within the RBCs due to clumps of denatured Hb from the periphery
what are heinz bodies associated with?
- G6PD deficiency
- exposure to certain drugs or oxidants
deficiency in G6PD can cause hemolytic anemia
what are Hb H inclusions?
(color, stain,..)
- bluish green granules
- precipitates of beta globin chains
- stained with supravital stain
what are Hb H inclusions associated with?
Hb H disease
what inclusions are stained with supravital stains?
- heinz bodies
- Hb H inclusions
what inclusion is a precipitate of beta globin chains?
Hb H inclusions
