Practical of Clinical
Hematology
RBC’s Morphology
RBCs Abnormal morphology
Peripheral Blood Morphology
Abnormal erythrocyte morphology

Is found in pathological states that may be
abnormalities in
I.
II.
III.
IV.
V.
Red cell distribution.
Size (anisocytosis).
Hemoglobin content – Color Variation .
Shape (poikilocytosis).
The presence of inclusion bodies in erythrocyte.
I. Erythrocyte Distribution Abnormalities

Rouleaux formation
Stacking of RBCs due to increased plasma proteins coating
RBCs (resembling a stack of coins)
Found in:
- Hyperfibrinogenaemia
- Hyperglobulinaemia

Agglutination
Antibody-mediated Irregular clumping , temperature
dependent
Found in:
- Cold agglutinins
- Warm autoimmune hemolysis
II. Variation in erythrocyte size (anisocytosis)

Anisocytosis: Variations in size
(Microcyte and Macrocyte)

Normocytic RBC’s
Normal size of RBC (8 μm) with a
range of 7 to 9 μm.
The nucleus of a small
lymphocyte (± 8 µm) is a useful
guide to the size of a red blood
cell).
Microcytic

RBC cell smaller than the normal RBC ( <7 μm), and is
associated with a decrease in hemoglobin synthesis
 Found in:
 Iron deficiency anemia.
 Thalassaemia.
 Sideroblastic anemia.
 Lead poisoning.
 Anemia of chronic disease.
Macrocyte

RBC larger than the normal (<9 μm) and is the result of a
defect in nuclear maturation or stimulated erythropoiesis.
May be round or oval in shape, the diagnostic significance
being different.

Found in:
 Folate and B12 deficiencies (oval)
 Ethanol (round)
 Liver disease (round)
 Reticulocytosis (round)
Example : Film Study
Most erythrocytes presented in
the picture are microcytes
(compare with the small
lymphocyte). The degree of
hemoglobinization is sufficient.
Normal platelets and single
ovalocytes are present.
1. microcyte 2. normocyte
III. Variation in erythrocyte color

A normal erythrocyte has a pinkish-red color with a slightly
lighter-colored center (central pallor) when stained with a
blood stain, such as Wright.

The color of the erythrocyte is representative of hemoglobin
concentration in the cell.

Under normal conditions, when the color, central pallor, and
hemoglobin are proportional, the erythrocyte is referred to
as Normochromic.
Hypochromia

Increased central pallor and decreased
hemoglobin concentration, the central pallor
occupies more than the normal third of the red
cell diameter.

Found in:
 Iron deficiency
 Thalassaemia
 any of the conditions
leading to Microcytosis
Polychromasia


Red cells stain shades of blue-gray as a consequence of
uptake of both eosin (by hemoglobin) and basic dyes (by
residual ribosomal RNA). Often slightly larger than normal red
cells and round in shape - round macrocytosis.
Found in:
Any situation with
reticulocytosis – for
example bleeding,
hemolysis or response to
heamatinic factor
replacement
IV. Shape Abnormalities of Erythrocytes

Poikilocytosis is the general term for mature erythrocytes
that have a shape other than the round, biconcave disk.

Poikilocytes can be seen in many shapes.(e.g.
Acanthocyte, Spherocytosis,……)
Shape Abnormalities of Erythrocytes
Terminology
Description
Condition
Target Cells
Central Hemoglobin; target
shaped
Liver Disease;Thalassaemia, Abnormal
Hb; Iron Deficiency
Echinocyte
Short specula's, equally-spaced
Uremia, Hypokalemia,Artifact
Acanthocyte
Speculated, Irregular
Liver disease (Alcohol), Postspleenoctomy.
Spherocyte
Spherical, no central pallor
HS, immune Hemolytic anemia
Shistocyte
Fragmented RBC, Helmet cells
MAHA, burns
Ovalocyte
Oval / Elliptical shaped
Hereditary elliptocytosis, Megaloblastic
anemia.
Sickle Cell
Bipolar speculated shape “
banana” shaped
Hb S-containing
hemoglobinopathy
Teardrop cell
Single elongated extremity
Myelophthistic changes
Bite cells
Irregular gap in membrane
G6PD deficiency
Target cell
Red cell with a “target” or bull’s-eye appearance. The
cell appears with a central bull’s eye that is surrounded
by a clear ring and then an outer red ring.
Found in:

Obstructive liver disease
Severe iron deficiency
Thalassaemia
Haemoglobinopathies (S and C)
Post splenectomy

Lipid disorders




Spherocytosis:
Red cells are more spherical. Lack the central area of pallor
on a stained blood film.
Found in:
 Hereditary spherocytosis
 Immune haemolytic anemia
 Zieve's syndrome
Microangiopathic haemolytic
Stomatocytosis:
Red cells with a central linear slit or stoma. Seen as mouthshaped form in peripheral smear.
Found in:
- Alcohol excess
- Alcoholic liver disease
- Hereditary stomatocytosis
Ovalocyte :

An elongated oval cell. They are a result of a
membrane defect.
Found in:
 Thalassaemia major.
 Hereditary ovalocytosis.
 Sickle cell anemia
Elliptocytosis:
The red cells are oval or elliptical in shape. Long axis
is twice the short axis.
Found in:
- Hereditary elliptocytosis
- Megaloblastic anemia
- Iron deficiency
- Thalassaemia
- Myelofibrosis
Schistocyte:


red cell fragments that are
irregular in shape and size. They
are usually half the size of the
normal RBC; therefore, they
have a deeper red color.
Found in:



DIC
Micro angiopathic haemolytic
anemia
Mechanical haemolytic anemia
Blister cell: pre keratocyte
Have accentric hallow area. Resemble a women's
handbag and may be called pocket-book cell.
Found in:
Microangiopathic hemolytic anemia
Keratocytes (horn cell)
Part of the cell fuses back leaving two or three horn-like
projections. The keratocyte is a fragile cell and remains in
circulation for only a few hours.
Found in:
- Uraemia
- Severe burns
- EDTA artifact
- Liver disease
Also called helmet cells
Degmacyte "bite cell"



An abnormally shaped red blood cell with one or more
semicircular portions removed from the cell margin.
These "bites" result from the removal of denatured
hemoglobin by macrophages in the spleen.
Found In:
 G-6-PD deficiency, in which
uncontrolled oxidative stress
causes hemoglobin to
denature and form Heinz
bodies, is a common
disorder that leads to the
formation of bite cells
Sickle Cells:
Sickle shaped red cells
Found in:
Hb-S disease and trait
Echinocyte “Burr” (crenation ) cell:
Red cell with 30 or more, short blunt projections which are regularly
distributed on their surface
Found in:
Usually artifactual— the result of slow drying under humid conditions.
Sometimes are non - artifactual, indicating uremia or pyruvate kinase
deficiency.
 Hemolytic anemia
 Uremia.
 Megaloblastic anemia
Cells retain the central pallor.
Echinocytes (Burr Cells)
Acanthocytosis (Spur Cells):
Red blood cells with irregularly spaced projections, these
projections very in width but usually contain a rounded end
Found in:
- Liver disease
- Post splenectomy
- Anorexia nervosa and starvation
Acanthocytes (Spur Cells)
Dacryocytes (Teardrop):

Resembles a tear and usually smaller than the normal RBC.
Found in:
 Bone marrow fibrosis
 Megaloblastic anemia
 Iron deficiency
 Thalassaemia
Envelope form cell

Found in


Thalassaemia
Sickle cell anemia
V. Erythrocyte Inclusions with Wright’s Stain
Inclusion
Composition
Appearance
Condition
Basophilic stippling
Precipitated
ribosomes
Evenly dispersed
fine or coarse
granules
- Lead poisoning
- Thalassaemia ,
other anemia.
Howell-Jolly bodies
DNA in origin
Nuclear Fragment
Dense, round blue
granule
Post – Splenectomy
Pappenheimer
bodies
Iron-containing
granules
Small blue granules
in clusters
Anemia's
Heinz bodies
Denatured
Hemoglobin
Round blue
precipitates
G6PD
Cabot Rings
Remnants of
Nuclear membrane
Reddish-blue thread Severe anemia, Lead
like rings
poisoning.
Organism
Small blue inclusion
Malaria
Babesiosis
Howell-Jolly Bodies:
Small round cytoplasmic red cell inclusion with same
staining characteristics as nuclei

Found in:


Post splenectomy
Megaloblastic anemia
Siderotic Granules (Pappenheimer Bodies)
These are iron containing granules in red blood cells that are
seen because the iron is aggregated with mitochondria and
ribosomes. They appear as faint violet or magenta specks,
often in small clusters, due to staining of the associated
protein.
They are associated with severe anemias and thalassemias.
Pappenheimer bodies can be increased in hemolytic anemia,
infections and post-splenectomy.
Basophilic stippling:
Considerable numbers of small basophilic inclusions in red
cells.
Found in:
- Thalassaemia
- Megaloblastic anemia
- Hemolytic anemia
- Liver disease
- Heavy metal poisoning.
Heinz Bodies:
Represent denatured hemoglobin (methemoglobin - Fe+++)
within a cell.
With a supravital stain like crystal violet, Heinz bodies appear as
round blue precipitates.
Presence of Heinz bodies indicates red cell injury and is usually
associated with G6PD-deficiency.
Heinz Body Preparation. RBC are incubated supravitally in new
Methylene blue to identify precipitates of oxidatively denatured
hemoglobin.
Cabot Rings:
Reddish-blue threadlike rings in RBCs of severe anemia's. These
are remnants of the nuclear membrane or remnants of
microtubules and appear as a ring or figure 8 pattern.
 Very rare finding in patients with
1. Megaloblastic anemia.
2. severe anemia's.
3. lead poisoning.
4. Dyserythropoiesis.
A - Cabot ring
B - Howell-Jolly body
Parasites of Red Cell:

Two organisms are have a tendency to invade the RBCs.
1.
All 4 species of the malaria parasite will invade RBCs. We will
see the Plasmodium of different species in RBCs.
2.
Theileria microti (Bebesia microti)
Malaria
RBCs Abnormal morphology
Depiction of red blood cell
morphologies that may
appear on a peripheral
smear, showing:
(A) basophilic stippling,
(B) Howell-Jolly bodies,
(C) Cabot's ring bodies and
(D) Heinz's bodies.
Blood Film in Some Cases
Normal Peripheral Smear
Autoimmune Hemolytic Anemia
Spherocytes
Hereditary Spherocytosis
Spherocytes
Hereditary pyropoikilocytosis
Microangiopathic Hemolytic Anemia
Schistocytes
Sickle Cell Anemia
Hb SS
Idiopathic myelofibrosis
Dacryocytes
Iron Deficiency Anemia
Severe Hypochromia
Treated Iron Deficiency Anemia
Mixed Population:
Alpha Thalassaemia (a-/--)
Microcytic Hypochromia
Morphologic Changes in Liver Disease
Target Cells
Spur Cells
Hepatorenal Syndrome
Burr + Spur Cells