2. Anemia
Anemia is present when a patient has a
reduced amount of hemoglobin per
unit volume of blood when compared
with the correct reference population
for that patient.
Males Hb-13-18
Females Hb 12-17
3. Anemia is generally defined as a hematocrit
<40% (hemoglobin <13.0 g/dL) in men or
<37% (hemoglobin <12.0 g/dL) in women.
(WHO definition)
Red blood cell (RBC) indices,
which include the mean corpuscular volume (MCV),
the mean corpuscular hemoglobin (MCH),
the mean corpuscular hemoglobin content(MCHC),
and
the red-cell distribution width (RDW) index, are
further used to define types of anemia.
4. Red Cell Indices
MCV defines the size of the red blood cells and is expressed
as femtoliters (10−15; fl) or as cubic microns (μm3). The
normal values for MCV are 87 ± 7 fl.
MCH quantifies the amount of hemoglobin per red blood
cell. The normal values for MCH are 29 ± 2 picograms (pg)
per cell.
MCHC indicates the amount of hemoglobin per unit volume.
In contrast to MCH,
MCHC correlates the hemoglobin content with the volume of
the cell. It is expressed as g/dl of red blood cells or as a
percentage value. The normal values for MCHC are 34 ± 2
g/dl.
7. Rouleaux
Rouleaux (singular is rouleau) are
stacks of red blood cells. They occur
when the plasma protein concentration
is high, and because of them the ESR
(erythrocyte sedimentation rate) is also
increased. Conditions which do this
include infections, inflammatory and
connective tissue disorders, and
cancers. In this case, the diagnosis is
probably multiple myeloma, as a plasma
cell can be seen on the film.
8. Erythroblasts & other BM cells
Erythroblasts are the
precursor cells of erythrocytes.
They contain nuclei, and in
adults are only found in the
bone marrow under normal
circumstances. Their presence
in the blood may indicate
either marrow 'stress', as in
hypoxia, severe sepsis, or
hemolysis, for example, or
some fundamental bone
marrow pathology such as
replacement by secondary
cancer.
9. Anisocytosis
Anisocytosis means that the red
cells are of unequal size. It is a
feature of many anemias, and
other blood conditions, and does
not have much diagnostic value.
The 'red cell distribution width'
(RDW) is a quantitative measure
of the degree of anisocytosis.
The RDW is useful in the
differential diagnosis of
microcytic anemia. Most cases
of iron deficiency have a raised
RDW, and most cases of
thalassemia trait have a normal
RDW.
10. Dimorphic Red Blood Cells
There are two
populations of red cells
present. One is
normocytic, and the
other is microcytic. This
occurs either because an
iron-deficient patient
has been transfused or
treated with iron, or in
the Sideroblastic
Anemias.
12. Classification of anemia
acute anemia , . A loss up to 10% of blood volume, as that taking
place upon blood donation, is well tolerated.
Losses between 10 and 20% cause postural hypotension, dizziness
and faint.
In losses above 20%, there's tachycardia, cold extremities, extreme
paleness and hypotension, followed by shock;
should the loss surmount 30%, without immediate replacement of
intravenous fluids, the shock rapidly becomes irreversible and
fatal.
In chronic anemia, there's no decrease in blood volume, which is
compensated by an increase in plasma volume.
14. Classification of anemia
Based on underlying process
Blood loss or def. of nutrients
Hemolysis
Failure of production
15. A diagnostic scheme for anemias
Determine the MCV
The Mean Corpuscular Volume (MCV)
represents a direct measurement of red cell
size.
When this is reduced, the anemia is referred to
as microcytic. It is macrocytic when the MCV
is increased,
and normocytic when the MCV is normal.
16. microcytic anemias, iron deficiency, thalassemia, sideroblastic anemia,
and the anemias of chronic disease.
Severe microcytic anemia (MCV <70 fL) is caused mainly by iron
deficiency or thalassemia.
Macrocytic anemia megaloblastic (folate or vitamin B12 deficiency) or
nonmegaloblastic causes. Folate deficiency can in turn be due to either
reduced intake or diminished absorption.
Severe macrocytic anemia (MCV >125 fL) is almost always
megaloblastic. In some rare cases, macrocytic anemia is related to the
myelodysplastic syndromes prior to or after chemotherapy.
The causes of normocytic anemias include aplastic anemia, bone-marrow
replacement, pure red-cell aplasia, anemias of chronic disease, hemolytic
anemia, and recent blood loss.
A number of anemias have a genetic etiology. Examples of such
inherited disorders include hereditary spherocytosis and sickle-cell (SC)
anemia
21. IDA-Practice Point
Iron def. is common in children 9mo-3yr
Iron def. anemia in a child over 3yr should
prompt consideration of occult blood loss.
Infants less than 6months generally do not
develop iron def.; the exception to this rule is
premature infants,who are at risk of iron def.at
4mo, if iron supplementation is not given.
22. Iron Deficiency Anemia-Diagnosis
Red blood cell count may be normal or
decreased.
Peripheral blood smear shows pale small
cells.
Aniso-poikilocytosis
White blood cell count usually normal
Serum iron is reduced
Total iron binding capacity of blood shows
an increase.
Low serum ferritin
23. Anemia of Chronic Disease
Patients with cancer, infection, or
inflammation, commonly have a mild-to-
moderate anemia caused by red cell
underproduction. This 'anemia of chronic
disease' is very common, and is usually
normocytic. Some cases develop
abnormalities of iron metabolism, in which
case there may be a microcytosis.
24. Hemolysis
Hemolysis is defined as the premature
destruction of red blood cells, from whatever
cause.
Recognising the presence of hemolysis
The simplest tests are
(a) Raised reticulocyte count
(b) Raised indirect (unconjugated) bilirubin
(c) Raised serum LDH
(d) Diminished serum haptoglobin concentration.
Further more sophisticated testing may be
needed in some cases.
25. Hemolysis
A Direct Coombs' Test tells you whether the
red blood cells are antibody-coated, and, in
the presence of hemolysis, indicates an
immune-mediated process (Autoimmune
hemolytic anemia).
28. Lead Poisoning
Hypochromic microcytic anemia
Associated iron deficiency
Child has pica and is exposed to lead paint or
lead dust
Blood smear shows basophilic stipling and
blood lead is elevated.
Removal from exposure,chelation therapy and
correction of iron deficiency are important.
29. THALASSEMIA
Normal Hb is a tetramer of 2 alpha and 2 beta
chains
Alpha-thalassemia:decrease or total lack of alpha
globin synthesis
Beta-thalassemia:decrease or total lack of beta
globin synthesis
31. G6PD deficiency
Episodic hemolysis on exposure to oxidants
Severity of hemolysis depends on the enzyme
variant
Gene for G6PD is on X chromosome
Jaundice,dark urine(bilirubin,hemoglobin),
Red cells appear blistered
G6PD levels may be normal with hemolysis
Prevention:avoid oxidants,fava beans,
32.
33. Howell–Jolly bodies are
histopathological findings of
basophilic nuclear remnants
(clusters of DNA) in circulating
erythrocytes.
During maturation in the bone
marrow late erythroblasts normally
expel their nuclei, but in some
cases a small portion of DNA
remains. Its presence usually
signifies a damaged or absent
spleen.
34. Cabot rings are thin, red-violet
staining, threadlike strands in the
shape of a loop or figure-8 that are
found on rare occasions in red
blood cells (erythrocytes). They are
believed to be microtubules that
are remnants from a mitotic
spindle, and their presence
indicates an abnormality in the
production of red blood cells.
35. Pappenheimer bodies are abnormal
granules of iron found inside red
blood cells on routine blood stain.
a type of inclusion body formed by
phagosomes that have engulfed
excessive amounts of iron. They
appear as dense, blue-purple
granules within the red blood cell
and there are usually only one or
two, located in the cell periphery.
They are seen in diseases such as
sideroblastic anemia, hemolytic
anemia, and sickle cell disease.
36. Acanthocyte refers to a form of
red blood cell that has a spiked cell
membrane, due to abnormal
thorny projections.
Acanthocytes have coarse,
irregularly spaced, variably sized
crenations, resembling many-
pointed stars. They are seen in,
abetalipoproteinemia, liver disease,
chorea acanthocytosis,
neuroacanthocytosis,anorexia
nervosa, hypothyroidism,
alcoholism,
37. Helmet cells
fragmented red blood cells that
appear"scooped out" so they
resemble helmets. in with micro-
angiopathic hemolytic anemia and
thrombotic thrombocytopenic
purpura. Helmet cells can also be
seen in blood samples of people
with prosthetic heart valves and in
individuals with unstable
hemoglobin conditions that
produce Heinz bodies.
38. The presence of
teardrop-shaped cells
may indicate:
Myelofibrosis
Severe iron deficiency
Thalassemia major
39. Presence of target cells may be due to:
Breakdown of red blood cells
(decreased osmotic fragility)
Deficiency of an enzyme called lecithin
cholesterol acyl transferase
Abnormalities of hemoglobin, the
protein in red blood cells that carry
oxygen (hemoglobinopathies)
Iron deficiency
Liver disease
Spleen removal
40. The presence of burr
cells (echinocytes) may
indicate:
Abnormally high level of
nitrogen waste products
in the blood (uremia)
