Red Blood Cell disorder

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RBCs disorder and common laboratory tests
By:
Hirut G/Michael (DVM,Lecturer)

Appril, 2018
Bishoftu, Ethiopia
08/30/18 By: Hirut Gebremichael 1

RBCs disorder and
common laboratory tests

Red Blood Cell Disorders
• Red blood cell (RBC) disorders are conditions
that affect red blood cells, the cells of blood
that carry oxygen from the lungs to all parts of
the body. There are many different types of
red blood cell disorders, including:

Anemia
• Red cell enzyme deficiencies (e.g. G6PD)
• Hemoglobinopathies (e.g. sickle cell
disease and thalassemia)
• Red cell membrane disorders among these;

A number of inherited red cell disorders due to
altered membrane function have been identified.
These include:
hereditary spherocytosis (HS),
hereditary elliptocytosis (HE),
hereditary ovalocytosis (HO), and
hereditary stomatocytosis (HSt).

• Most RBC diseases are lifelong, chronic
conditions that result in anemia, a reduction in
the ability to carry oxygen to tissues due to
reduced numbers of RBCs in blood, or a
reduction in the amount or function of
hemoglobin in the RBCs….

The latter diseases are also known as
hemoglobinopathies, and include sickle cell
disease (caused by a less functional hemoglobin
beta, selected via malaria parasite), as well as
beta and alpha thalassemia (like sickle cell trait)

• Thalassemia is an inherited blood disorder in
which the body makes an abnormal form of
hemoglobin
• The disorder results in excessive destruction of
red blood cells, which leads to anemia
• It’s caused by either a genetic mutation or a
deletion of certain key gene fragments.

RED BLOOD CELL MORPHOLOGY
Abnormal erythrocyte morphology is found in
pathological states that may be :
I. abnormalities in size (anisocytosis).
II.In shape (poikilocytosis).
III.In hemoglobin content or the presence of
inclusion bodies in erythrocyte.

I-Variation in erythrocyte size
(anisocytosis)
1-Microcytosis:
- Decrease in the red cell size. Red cells are smaller
than ± 7µm in diameter. The nucleus of a small
lymphocyte (± 8,µm) is a useful guide to the
size of a red blood cell.

Found in:
• Iron deficiency anemia.
- Thalassaemia.
- Lead poisoning.
- Anemia of chronic disease
• Sideroblastic anemia
Sideroblastic anemia: is a form of anemia in which
the bone marrow produces ringed sideroblasts
rather than healthy red blood cells .08/30/18 By: Hirut Gebremichael 11

• In sideroblastic anemia, the body has iron available
but cannot incorporate it into hemoglobin, which
red blood cells need in order to transport oxygen
efficiently. The disorder may be caused either by
a genetic disorder or by hematological
malignancies (especially acute myeloid leukemia)

2-Macrocytosis:
Macrocytosis is a term used to describe red blood
cells that are larger than normal. It typically
causes no signs or symptoms and is usually
detected incidentally on routine blood tests.
Macrocytosis isn't a specific disease, but it may
indicate an underlying problem that requires
medical evaluation.

• Common causes of macrocytosis include:
• Vitamin B-12 deficiency
• Folate deficiency
• Liver disease
• Alcoholism(Human)
• Hypothyroidism08/30/18 By: Hirut Gebremichael 15

II-Variation in hemoglobin content
1-Hypochromasia:
Hypochromia is characterized by an increase in
central pallor. It is said to be present when
greater than 1/2 of the cell diameter has central
pallor.

• Hypochromia is caused by a deficiency in the
production of hemoglobin, which is usually
the result of iron deficiency caused by chronic
hemorrhage.

2- Polychromasia:
• Polychromasia is a disorder where there is an
abnormally high number of immature red
blood cells found in the bloodstream as a result
of being prematurely released from the bone
marrow during blood formation

• Poly- refers to many, and -chromasia means color.
• Polychromasia is usually a sign of bone marrow
stress as well as immature red blood cells.
• 3 types are recognized, with types (1) and (2) being
referred to as 'young red blood cells' and type (3) as
'old red blood cells'.
• Giemsa stain is used to distinguish all three types in
blood smears.08/30/18 By: Hirut Gebremichael 19

Found in:
Any situation with reticulocytosis - for example
bleeding, hemolysis or response to haemostatic
factor replacement.
supravital Stain

III- Variation of red cells shape
(Poikilocytosis)
RBCs may have different shapes:
1- Spherocytosis:
Red cells are more spherical. Lack the central area
of pallor on a stained blood film.
Found in:
- Hereditary spherocytosis
- Immune haemolytic anemia08/30/18 By: Hirut Gebremichael 21

Spherocytosis

2-Target Cells:
• Codocytes also known as target cells are red
blood cells that have the appearance of a
shooting target with a bullseye.

• In optical microscopy these cells appear to
have a dark center (a central, hemoglobinized
area) surrounded by a white ring (an area of
relative pallor), followed by dark outer
(peripheral) second ring containing a band of
hemoglobin.

Target cells or codocytes (black arrows) appear as a target
with a bullseye. Dog, blood smear, Wright stain.

Found in:
-Obstructive liver disease
- Severe iron deficiency
- Thalassaemia
- Haemoglobinopathies
- Post splenectomy

3- Ovalocytes:
oval shape red blood cell
Found in:
- Thalassaemia major.
- Hereditary ovalocytosis.
- Sickle cell anemia

4- 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

5- Tear Drop Cells:
Red cells shaped like a tear drop or pear
Found in:
- Bone marrow fibrosis
- Iron deficiency
- Thalassaemia

6- Blister cell:
A degmacyte (a.k.a. "bite cell") is 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.

Glucose-6-phosphate dehydrogenase 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.
Found in:
 Microangiopathic hemolytic anemia
 G6PD deficiency

7- Schistocytosis:
Fragmentation of the red cells.
Found in:
- DIC
- Micro angiopathic haemolytic anemia
- Mechanical haemolytic anemia

8- Stomatocytosis:
Red cells with a central linear slit or stoma.
Seen as mouth-shaped form in peripheral
smear.
Found in:
- Hereditary stomatocytosis
- Hereditary spherocytosis

9- Burr (crenation ) cell:
Red cell with uniformly spaced, pointed
projections on their surface.
Found in:
- hemolytic anemia
- Uremia.

10- 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

are 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 and starvation
11- Acanthocytosis:

12- Sickle Cells:
Sickle shaped red cells
Found in:
Hb-S disease

13- Rouleaux Formation:
Stacks of RBC's resembling a
stack of coins.
Found in:
- Hyperfibrinogenaemia
- Hyperglobulinaemia

14- Red cell-agglutination:
Irregular clumps of red cells
Found in:
- Cold agglutinins
- Autoimmune hemolysis

15- Nucleated red blood cells.
These red blood cells are released
from the bone marrow early into the
blood stream, due to the need for
oxygen. Normal red blood cells do
not contain a nucleus on a
peripheral smear.

IV -Erythrocyte inclusion bodies
1- Howell-Jolly Bodies:
Small round cytoplasmic red cell
inclusion with same staining
characteristics as nuclei
Found in:
- Post splenectomy

2- Siderotic Granules (Pappenheimer
Bodies)
RBCs which contain no hemoglobin iron granules. They
appear as dense blue, irregular granules which are
unevenly distributed in Wright stained
RBCs. Pappenheimer bodies can be increased in
hemolytic anemia, infections and post-splenectomy.

3- Basophilic stippling:
Considerable numbers of small
basophilic inclusions in red cells.
Found in:
- Hemolytic anemia
- Liver disease
- Heavy metal poisoning.

4- 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.

5- Cabot Rings:
Reddish-blue threadlike rings in RBCs of severe
anemia's. These are remnants of the nuclear
membrane and appear as a ring or as the figure
pattern. Very rare; finding in patients with
Megaloblastic anemia, severe anemia's, lead
poisoning, and dyserythropoiesis.

6- Parasites of Red Cell:
are protozoan parasites which occur in many
species of birds and are the cause of avian
malaria. Transmitted by mosquitoes, infection
with Plasmodium can be a cause of hemolytic
anemia

Common Laboratory Tests

Let’s look at some nuances of 2 of most
commonly ordered lab tests
I. CBC (Complete Blood Count)
II. Blood chemistry test(Basic and Complete
metabolic panels)

CBC
• This is the most common blood test performed
on pets and people. A CBC gives information
on hydration status, anaemia, infection, the
blood's clotting ability, and the ability of the
immune system to respond.

• This test is essential for pets with fevers,
vomiting, diarrhoea, weakness, pale gums, or
loss of appetite. If your pet needs surgery, a
CBC can detect some bleeding disorders or
other unseen abnormalities.

• Peripheral venous blood is collected in a
lavendar tube (contains the anticoagulant
EDTA) and should be thoroughly mixed.

• Unacceptable specimen:
– Clotted or greater than 48 hours old
• Methodology of testing:
– Whole blood analyzer

What is measured?
• Red blood cell data
– Total red blood cell count (RBC)
– Hemoglobin (Hgb)
– Hematocrit (Hct)
– Mean corpuscular volume (MCV)
– Red blood cell distribution width (RDW)08/30/18 By: Hirut Gebremichael 58

Total Red Blood Cell Count
• Count of the number of circulating red blood
cells in 1mm3
of peripheral venous blood

Hemoglobin
• The hemoglobin concentration is a measure of
the amount of Hgb in the peripheral blood,
which reflects the number of red blood cells in
the blood
Result interpretation
– Hgb constitutes over 90% of the red blood
cells08/30/18 By: Hirut Gebremichael 60

• Decrease in Hgb concentration = anemia
• Increase in Hgb concentration = polycythemia
Hematocrit
Hematocrit is a measure of the percentage of the
total blood volume that is made up by the red
blood cells.

• The hematocrit can be determined directly by
centrifugation (“spun hematocrit”)
– The height of the red blood cell column is
measured and compared to the column of
the whole blood

Centrifuged blood (normal)
Red blood cells
Buffy coat (WBCs and Platelets)
Plasma
Normal Hct in adult males
40-54%
Normal Hct in adult females
34-51%

Centrifuged blood
Anemia – there is a low percentage of RBCs
(low hematocrit)
RBCs
Buffy coat
Plasma

Results
The percentage of the volume of blood occupied
by the red cells constitutes hematocrit or packed
cell volume.
Hct % = {Height of RBCs (mm) / Height of
RBCs and plasma (mm)} × 100
For example, if the height of packed red cells is
45 mm, then
= 45/ 100 × 100 = 45 percent.

It also means that out of 100 volumes (or parts)
of blood 45 volumes (or parts) are red cells
and 55 volumes (or parts) are plasma. Thus,
out of 1 liter of blood, 450 ml are red cells and
550 ml are plasma.

Mean Corpuscular Volume (MCV)
• It is defined as the average volume of red
cell
• It Provides information on red cell size
• It is measured in femtolitres.
• Normal range = 87±5fl
• 1fL= L
• It is determined by the distribution of the08/30/18 By: Hirut Gebremichael 67

Cell Size (fl)
Number
Of
cells
60 120
MCV
Red Cell Distribution Histogram

Use of MCV Result
• The MCV is important in classifying anemias
– Normal MCV = normocytic anemia
– Decreased MCV = microcytic anemia
– Increased MCV = macrocytic anemia

Cell Size (fl)
Number
Of
cells
60 120
MCV
Red Cell Distribution Histogram
Microcytic
Red blood cells
Macrocytic
Red blood cells

Red Blood Cell Distribution Width
• RDW is a measure of the range of variation of
red blood cell (RBC) volume that is reported as
part of a standard complete blood count.
• Usually red blood cells are a standard size of
about 6-8 μm in diameter. Certain disorders,
however, cause a significant variation in cell
size. 08/30/18 By: Hirut Gebremichael 72

• In general, an elevated RDW (indicating more
variation in the size of RBCs) has been
associated with anemias with various
deficiencies, such as iron, B12, or folate
• Thalassemia is a microcytic anemia that
characteristically has a normal RDW

Mean Corpuscular Hemoglobin
It is defined as the amount of hemoglobin in
average red cell Or Average amount of Hb in
all the red cell
•It is directly proportional to the amount of
hemoglobin and the size of the erythrocyte
•Normal range = 27-32pg
•1pg = 08/30/18 By: Hirut Gebremichael 74

Formul
a

Interpretation of MCH values
• Low MCH values: are found in microcytic
hypochromic anaemias and also when red
cells are microcytic and normochromic. In
thalassaemia the MCH is low even when
anaemia is mild (MCHC is often normal)
• Raised MCH values: found in macrocytic
normochromic anaemia

Mean Corpuscular Hemoglobin
Concentration (MCHC)
• The MCHC expresses the average
concentration of hemoglobin per unit volume
of erythrocytes.
• It is expressed in percentage.
• Normal value = 32-36%

B a s i c
formula
o
r

Interpretation of MCHC values
• Low MCHC values are found in iron deficiency
anemia and other conditions in which the red
cells are microcytic and hypochromic.
• An increased MCHC can occur in marked
spherocytosis.

Peripheral Blood Smear
• A small drop of the blood is placed on a slide
and spread out into a thin film. After drying, it
is stained with Wright's stain in an automatic
stainer.

• The stained slide can the be viewed under a
microscope, and the hematologist can assess the
morphology and appearance of all the blood
elements: the red blood cells, the white blood cells
and the platelets.

Erythrocyte Sedimentation Rate(ESR)
• Anticoagulated blood is placed in a thin tube
to stand for two hours. The red blood cells
(RBCs) settle to the bottom of the tube and a
top layer of plasma is left in the tube.

• The result is seen through the number of
millimeters the RBCs fall in one to two hours.
The speed at which the RBCs fall is
determined by the concentration of a number
of plasma proteins which rise during acute
illnesses.

• A high sedimentation rate is a nonspecific, but
highly sensitive, indicator for the presence of
diseases of all sorts.

Westergren pipet array on StaRRsed automated
ESR analyzer

Tests of the Coagulation System
• There are many types of tests of the coagulation
system, and these are categorized into routine
tests, bleeding diathesis (tendency to bleed),
• hypercoagulability tests (excess blood
clotting)

• There is a whole array of indicators for tests
related to the coagulation system. Some of
these tests are performed routinely in a number
of medical situations, such as prior to major
surgical procedures.

• They may also be performed if there is
evidence of a bleeding problem, such as easy
bruising. Alternatively, other tests are
performed if there is evidence of a disorder
leading to excessive blood clotting
(thrombosis).

Blood chemistries
• These common blood serum tests evaluate organ
function, electrolyte status, hormone levels and
more. They are important in evaluating older pets,
pets with vomiting, diarrhoea or toxin exposure,
pets receiving long-term medications and health
before anaesthesia.08/30/18 By: Hirut Gebremichael 89

• A veterinary chemistry panel (also termed
'biochemical profile') includes tests for
multiple chemical constituents within one
sample. The quantities of these chemicals can
reveal many things about the various organs of
the body. Most veterinary chemistry panels
check blood electrolyte and for diseases of the
liver, kidneys, and pancreas

• A small quantity of the serum from the original
collection is drawn into a single large machine.
Tiny samples from that serum are tested for
various chemical components. The results of each
test are compiled and printed out on a single
form. To make it easier for veterinarians and
physicians, the form lists the patient's results
along with the expected normal values for that
species08/30/18 By: Hirut Gebremichael 91

Types of panels
• Since the laboratory equipment has the ability
to run numerous different tests, there can be
many different chemistry panels (e.g., liver
panels, electrolyte panels, geriatric panels, pre-
surgical panels) produced depending upon
which individual tests are requested and
included.

A typical veterinary chemistry panel will
measure the following

Thank You!

Red Blood Cell disorder

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