Clinical laboratory
diagnostics of
anemias
Actuality of theme:
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Anemia is very often
met in 20% women of
the developed
countries and in 50%
women of the nondeveloped countries;
More than 50%
patients with chronic
diseases and tumors;
Considerably worsens
quality of life and
capacity.
Anemia is the decreasing of hemoglobin and red blood
cells level in the unit of blood volume
Reduction in one or more of the major red blood
cell (RBC) measurements:
Hemoglobin concentration
Hematocrit
RBC count
From data of WHO:
a hematocrit less than 40 in men and 37 in
women, or hemoglobin less than 130 g/l in men
and less than 120 g/l in women.
Anemia
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• Decrease in the number of circulating red
blood cells
 • Most common hematologic disorder by far
 • Almost always a secondary disorder
 • As such, critical for internist to know how
to evaluate/determine cause
Anemia Symptoms
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Because a low red blood cell count
decreases oxygen delivery to every tissue
in the body, anemia may cause a variety
of signs and symptoms. It can also make
almost any other underlying medical
condition worse. If anemia is mild, it may
not cause any symptoms. If anemia is
slowly ongoing (chronic), the body may
adapt and compensate for the change; in
this case there may not be any symptoms
until the anemia becomes more severe.
Signs and symptoms
Signs of anemia :
• Black and tarry stools (sticky and foul
smelling)
• Maroon, or visibly bloody stools
• Rapid heart rate
• Rapid breathing
• Pale or cold skin
• Yellow skin called jaundice
• Low blood pressure
• Heart murmur
• Enlargement of the spleen
Signs and symptoms
Symptoms of anemia may include the
following:
• Fatigue
• Chest pain
• Abdominal pain
• Weight loss
• Weakness
• Dizziness and passing out, especially
upon standing
Anemia Symptoms
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Fatigue
decreased energy
weakness
lightheadedness
palpitations (feeling of the heart racing or
beating irregularly)
looking pale
Symptoms of severe anemia may
include:
chest pain, angina, or heart attack
 dizziness
 fainting or passing out
 rapid heart rate
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Symptoms of severe anemia may include:
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Change in stool color, including black and tarry stools (sticky
and foul smelling), maroon-colored, or visibly bloody stools if the
anemia is due to blood loss through the gastrointestinal tract.
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rapid heart rate
low blood pressure
rapid breathing
pale or cold skin
yellow skin called jaundice if anemia is due to red blood
cell breakdown
heart murmur
enlargement of the spleen with certain causes of anemia
Depending on the level of hemoglobin in
the blood anemia is divided on:
- mild degree (Hb 110-90 g/l),
- moderate degree (Hb 89-70 g/l),
- severe degree (Hb less than 69 g/l).
Depending on the size of RBC and their
saturation by hemoglobin (from data of colour
index - CI) anemia is divided on:
- Normocytic anemia (can be normochromic anemia:
colour of RBC is normal and CI is 0,86-1,1);
- Microcytic anemia (can be hypo- or normochromic):
microcytosis , anizopoykilocytosis, hypochromia, CI <
0,7;
- Macrocytic anemia: macrocytosis, megalocytosis, CI
> 1,1.
Approaches to Anemia
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Kinetic approach
Decreased RBC
production
Increased RBC
destruction
Blood loss
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Morphologic approach
Macrocytic
Normocytic
Microcytic
Decreased RBC Production
Nutrient deficiency
Dietary, malabsorption
 Bone marrow disorders/suppression
Anemia of chronic diseases
Low levels of trophic hormones
Epo, thyroid hormone, androgens
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Increased RBC Destruction
Blood Loss
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Most common cause of anemia
Fe deficiency almost always due to blood
loss
Obvious bleeding
Occult bleeding
Induced bleeding
Operative blood loss
Clinical classification of anemia is
based on morphological prinsiple determination of mean corpuscular
volume (MCV) of red blood cells
MСV- is determined by automatic
laboratory analyzers or by such
formula: MСV = (hematocrit x10) /
amount of RBC (in mln/l).
Definition of MEAN CORPUSCULAR
VOLUME
: the volume of the average red blood cell
in a given blood sample that is found by
multiplying the hematocrit by 10 and
dividing by the estimated number of red
blood cells—abbreviation MCV
First use size (MCV) to sort the
Differential Dx
MCV
Micro
Normo
Macro
Normocytic anemia (MCV - 80-100)
•A loss or destruction of RBC is increased
-Acute bleeding
-Early iron deficiency
- Hemolytic anemia
- Hypersplenism
•Decreasing of RBC synthesis
-Anemia of chronic diseases (most commonly)
-Endocrine dysfunctions
-Renal insufficiency
•Pathology of bone marrow (for example, action of
medications, infection, aplastic anemia, myelodysplastic
syndrome, multiple myeloma and other infiltrative
diseases).
Anemia of Chronic Disease
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•Common
• Develops over 1 to 2 months
• Non-progressive
• Usually mild to moderate
– but hematocrit < 0.20 occasionally
• 30% mildly microcytic
• WBC, platelets normal or increased
ANEMIA OF CHRONIC DISEASE
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• Thyroid disease
• Collagen Vascular Disease
– Rheumatoid Arthritis
– Systemic Lupus Erythematosus
– Polymyositis
– Polyarteritis Nodosa
• Inflammatory Bowel Disease
– Ulcerative Colitis
– Crohn’s Disease
• Malignancy
• Chronic Infectious Diseases
– Osteomyelitis
– Tuberculosis
• Familial Mediterranean Fever
Normocytic Anemia (MCV 80-100 fl)
Type of
anemia
Blood film
Ferritin
Fe
Nl or ↑
↓
Early Fe Mild anisocytosis Nl or ↓
deficien hypochromia
cy
↓
Chronic Normochromic,
disease* normocytic
TIBC Marrow
Fe stores
↓
↑
*including anemia due to renal disease and AIDS
Nl or ↑,
clumped
absent
Hemolytic Anemia
• Anemia of increased destruction
 normochromic anemia
 – Shortened RBC survival
 – Reticulocytosis - Response to increased
RBC
 Destruction
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Hemolytic Anemia
Coombs’ (DAT)
Positive
Immune Hemolysis
Drug related Hemolysis
Transfusion, Infection, Cancer
Negative
Hemoglobinopathy, G6PD, PK,
Spherocytosis, Eliptocytosis,
PNH, TTP, DIC
Equired hemolytic anemia
Reticulocytosis
Equired hemolytic anemia
Reticulocytosis
Hereditary disorders
include erythrocyte membrane and enzymatic
defects and hemoglobin abnormalities. Some
hereditary disorders include the following:G6PD
deficiency
Herediditary spherocytosis
Sickle cell anemia
Thalassemia
Acquired hemolytic conditions
can be due to immune disorders, toxic
chemicals and drugs, antiviral agents (eg,
ribavirin) physical damage, and infections
Autoimmune hemolytic anemia (AIHA) may result
from warm or cold autoantibody types; rarely, mixed
types occur. Most warm autoantibodies are
immunoglobulin (Ig) G and can be detected with the
direct Coombs test, which is also known as the direct
antiglobulin test (DAT)
Acquired hemolytic conditions
•AIHA may occur after allogeneic
hematopoietic stem cell transplantation
•Microangiopathic anemia is found in patients
with disseminated intravascular coagulation
(DIC) or hemolytic uremic syndrome (HUS)
and thrombotic thrombocytopenic purpura.
Fragmented erythrocytes (schistocytes) also
occur with defective prosthetic cardiac valves.
Acquired hemolytic conditions
•Autoimmune hemolytic anemia and hereditary
spherocytosis are classified as examples of
extravascular hemolysis because the red blood
cells are destroyed in the spleen and other
reticuloendothelial organs.
•Intravascular hemolysis occurs in hemolytic
anemia due to prosthetic cardiac valves, G6PD
deficiency, thrombotic thrombocytopenic
purpura, disseminated intravascular coagulation,
and paroxysmal nocturnal hemoglobinuria
(PNH).
Peripheral blood smear with sickled cells
Spherocytes. One arrow points to a
spherocyte; the other, to a normal RBC
with a central pallor.
Schistocytes (thrombotic
thrombocytopenic purpura).
Hemolytic anemia due to pyruvate
kinase insefficiency. Reticulocytosis
Membranopathy
Hereditary microspherocytosis - blood
Membranopathy
Hereditary eliptocytosis – blood
Microcytic anemia
(MCV less than 80)
Usually hypochromic as well
Iron-deficiency anemia
Anemia of chronic diseases(rare)
Sideroblastosis
Hereditary anemia (thalassemia)
Lead poisoning
Deficit of copper, poisoning by zinc
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Iron Absorption
• Mechanism not well understood
 • Only mechanism to regulate stores is
through absorption
 • Occurs in duodenum & upper jejunum
 • Heme forms better absorbed than free iron
 – Meat forms better absorbed than plant
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Iron Absorption
• Stomach acid converts ferric (insoluble) to
ferrous (absorbable) state
 Decreased absorption w/ acid blockers
 Increased w/ citrate & ascorbate
(chelators)
 Increased absorption w/ orange juice
 Decreased w/ plant phytates, tannins, soil
clay, & laundry starch
 – Pica may exacerbate Fe deficiency
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Iron Absorption
• Increased erythropoesis greatly enhances
Fe absorption
 – Increased erythropoesis (thalassemia,
sickle cell) may lead to Fe overload
independent of transfusions
 • Co-regulated with other metal absorption
 – Lead poisoning -> Fe deficiency -> increased
lead absorption
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Iron Deficiency
Causes
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– Blood loss
• GI tract
• Renal (rare)
• Pulmonary (rare)
– Insufficient dietary iron
Decreased absorption
Consequences of Iron Deficiency
Hematologic
• Microcytic, hypochromic anemic
 • Low grade hemolysis d/t stiff RBC
membrane
 • Thrombocytosis w/ plts 500-700k
 – Erythropoietin may cross react w/ plt
 Precursors
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Makrocytic anemia
(MCV more than 100 fl)
- Megaloblastic anemia (vitamin В12 or folic acid
deficiency )
- Toxic effect of chemotherapeutic agents
(methotrexate) or other medications (zidovudine
(AZT), phenytoin)
- Pathology of bone marrow
- Chronic abuse by alcohol (toxic effect)
- Liver disease
Macrocytosis (MCV > 100 fl)
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•Common
– Drugs (cytotoxics, immunosuppressants, AZT,
anticonvulsants)
– Alcohol
– Liver disease
– Reticulocytosis
–B12/folate deficiency
– Myelodysplastic syndrome
– Marrow infiltration (malignancy, fibrosis)
• Less common
–Aplasia
– Cold agglutinins
– Hyperglycemia
Macrocytosis of Alcoholism
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25-96% of alcoholics
MCV elevation usually slight (100-110 fl)
Minimal or no anemia
Macrocytes round (not oval)
Neutrophil hypersegmentation absent
Folate stores normal
Megaloblastic Hematopoiesis
• Marrow failure due to: disrupted DNA synthesis
& ineffective hematopoiesis
 • Giant precursors and nuclear:cytoplasmic
dyssynchrony in marrow
 • Neutrophil hypersegmentation & macroovalocytes
in blood
 • Anemia (and often leukopenia &
thrombocytopenia)
 • Almost always due to Cbl or folate deficiency
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Megaloblastic Anemia
Smear
 Macro-ovalocytic
 Polychromasia
 Hypersegmented
neutrophil
ANEMIA CAUSES
•External bleeding: Loss of blood through heavy menstrual
bleeding, wounds, as well as stomach ulcers can cause anemia.
•Iron deficiency: The bone marrow needs iron to make red
blood cells.
•Anemia of chronic disease: Any long-term medical condition
can lead to anemia.
•Kidney disease: The kidneys help the bone marrow to make
red blood cells.
•Pregnancy: Water weight gain during pregnancy dilutes the
red blood cells.
•Poor nutrition: Vitamins and minerals are required to make
red blood cells.
•Alcoholism.
•Uncommon causes of anemia: bleeding disorders, liver
disease, thalassemia, infection, cancer, arthritis, enzyme
deficiency, sickle cell disease, hypothyroidism, toxins, or
hereditary conditions.
Diagnosis
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The only way to diagnose anemia is with a blood
test. Generally, a full blood count is done. Apart
from reporting the amount of red blood cells and
the hemoglobin level, the automatic counters also
measure the size of the red blood cells, which is an
important tool in distinguishing between the
causes.
Occasionally, other tests are required to further
distinguish the cause for anemia. These are
discussed with the differential diagnosis. The
doctor may also decide to take some other
screening blood tests that might identify the cause
of fatigue; glucose levels, ESR, ferritin, renal
function tests and electrolytes may be part of such
Lab tests for anemia may include the
following:
1. Complete blood count - Determines the severity of the
anemia and is almost always the first test ordered
2. Stool guaiac - Tests for blood in stool
3. Peripheral blood smear - Looks at the red blood cells
under a microscope
4. Iron level - Low iron is one of the most common causes
of anemia
5. Transferrin level - Looks at a protein that carries iron
around the body
6. Ferritin - Looks at the total iron available in the body
7. Folate - A vitamin needed to produce red blood cells,
which is low in people with poor eating habits
• Vitamin B12 - A vitamin needed to produce red blood
cells, low in people with poor eating habits
• Bilirubin - Useful to determine if the red blood cells
are being destroyed within the body
• Lead level - Lead toxicity used to be one of the more
common causes of anemia
• Hemoglobin electrophoresis - Sometimes used when a
person has a family history of anemia
• Reticulocyte count - A measure of new red blood cells
produced by the bone marrow
• Liver function tests - Uncommon tests to determine
how the liver is working
• Bone marrow biopsy - One of the last tests done; looks
at production of red blood cells
Thank you for attention!