Introduction to Introduction to anemiaanemia

Gülay ÇİLER ERDAĞ,MDGülay ÇİLER ERDAĞ,MD

HematopoiesisHematopoiesis Begins in the embryo during the third week of gestationBegins in the embryo during the third week of gestation

Developmental hematopoiesis occurs in three Developmental hematopoiesis occurs in three stagesstages MesoblasticMesoblastic

In the yolk sac first produces erythrocytes and leukocytesIn the yolk sac first produces erythrocytes and leukocytes

HepaticHepatic By the 12th week of gestation liver and the spleen are the By the 12th week of gestation liver and the spleen are the

predominant sitespredominant sites

MyeloidMyeloid By the 30 weeks gestation, the bone marrow assumes its ultimate By the 30 weeks gestation, the bone marrow assumes its ultimate

role as the major site of production of the formed elements of the role as the major site of production of the formed elements of the bloodblood

Age Site of hematopoiesis

Embryo yolk sac then liver

3rd to 7th month

Spleen and liver

4th and 5th months

marrow cavity - esp. granulocytes and platelets

7th month marrow cavity - erythrocytes

Birthmostly bone marrow; spleen and liver when needed

Birth to maturity

number of active sites in bone marrow decreases but retain ability for hematopoiesis

Adultbone marrow of skull, ribs, sternum, vertebral column, pelvis, proximal ends of femurs

The predominant cellular element in the The predominant cellular element in the

blood is eryhtrocyte: RBC (red blood cell)blood is eryhtrocyte: RBC (red blood cell) Under the stimulus of erhythropoietin and Under the stimulus of erhythropoietin and

other humoral factors other humoral factors erythroid burst forming units (from the pluripotent erythroid burst forming units (from the pluripotent

stem cells) and colony forming units give rise to stem cells) and colony forming units give rise to

identifiable erythroblastsidentifiable erythroblasts Begin to synthesize HbBegin to synthesize Hb

Nucleated RBCNucleated RBC Nucleus extruded Nucleus extruded Young erythrocyte Young erythrocyte

HbHb Binds to oxygen in the lungs and transports it Binds to oxygen in the lungs and transports it

to the tissuesto the tissues

Tetramer consisting of two pairs of unlike Tetramer consisting of two pairs of unlike

polypeptide chains each attached to a HEME polypeptide chains each attached to a HEME

( molecule of protoporphyrin ferrous iron)( molecule of protoporphyrin ferrous iron) The primary Hb The primary Hb

in the postnatal life is HbA (2in the postnatal life is HbA (2αα22ββ)) Initial months of gestation HbF (2Initial months of gestation HbF (2αα22γγ))

At the time of birth At the time of birth γγ and and ββ chain synthesis is chain synthesis is approximately equal and 60%-80% of the total approximately equal and 60%-80% of the total Hb is HbFHb is HbF

γγ glb synthesis almost ceases during the initial glb synthesis almost ceases during the initial months of lifemonths of life By 6 months of age the percentage of HbF By 6 months of age the percentage of HbF

approximates that of adults(<2%)approximates that of adults(<2%) HbF is resistant to both alkali and dilute acid. It binds HbF is resistant to both alkali and dilute acid. It binds

less avidly than does HbA to 2,3 diphosphoglycerate less avidly than does HbA to 2,3 diphosphoglycerate an organic phosphate in the erythrocyte important in an organic phosphate in the erythrocyte important in

modulating oxygen uptake and release by Hbmodulating oxygen uptake and release by Hb The affinity of HbF for oxygen is highThe affinity of HbF for oxygen is high

Because of intrauterine hypoxia and Because of intrauterine hypoxia and the high affinity of HbF for the high affinity of HbF for oxygen(resulting in a shift to the left oxygen(resulting in a shift to the left of oxygen-Hb dissociation curve)of oxygen-Hb dissociation curve) Erythropoietin secretion is enhanced Erythropoietin secretion is enhanced

during fetal life during fetal life During the final months of gestation and During the final months of gestation and

at birth values for Hb and Hct are higher at birth values for Hb and Hct are higher than those for older childrenthan those for older children

Hemoglobin F (Hb F), Hemoglobin F (Hb F), composed of 2 alpha and 2 composed of 2 alpha and 2 gamma globin chains, is the gamma globin chains, is the normal hemoglobin of the fetus normal hemoglobin of the fetus and newborn. Normally in the and newborn. Normally in the second trimester, gamma second trimester, gamma chain production (and Hgb F chain production (and Hgb F levels) decrease and beta levels) decrease and beta chain production increases, chain production increases, resulting in increasing levels of resulting in increasing levels of hemoglobin A (Hb A), the major hemoglobin A (Hb A), the major normal adult hemoglobin (2 normal adult hemoglobin (2 alpha and 2 beta globin alpha and 2 beta globin chains). Hemoglobin A2 (Hb chains). Hemoglobin A2 (Hb A2) (2 alpha and 2 delta globin A2) (2 alpha and 2 delta globin chains) also comprises a small chains) also comprises a small amount (<3.3%) of hemoglobin amount (<3.3%) of hemoglobin normally found in adults. Hb A2 normally found in adults. Hb A2 values at birth are <1%.values at birth are <1%.

Reference Values Reference Values HEMOGLOBIN A2HEMOGLOBIN A2 1-30 days: 0.0-2.1%1-30 days: 0.0-2.1% 1-2 months: 0.0-2.6%1-2 months: 0.0-2.6% 3-5 months: 1.3-3.1%3-5 months: 1.3-3.1% > or =6 months: 2.0-3.3%> or =6 months: 2.0-3.3% HEMOGLOBIN FHEMOGLOBIN F 1-30 days: 22.8-92.0%1-30 days: 22.8-92.0% 1-2 months: 7.6-89.8%1-2 months: 7.6-89.8% 3-5 months: 1.6-42.2%3-5 months: 1.6-42.2% 6-8 months: 0.0-16.7%6-8 months: 0.0-16.7% 9-12 months: 0.0-10.5%9-12 months: 0.0-10.5% 13-17 months: 0.0-7.9%13-17 months: 0.0-7.9% 18-23 months: 0.0-6.3%18-23 months: 0.0-6.3% > or =24 months: 0.0-0.9%> or =24 months: 0.0-0.9%

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Newborns less than one week old have Newborns less than one week old have hemoglobin of 14-22 g/dl. hemoglobin of 14-22 g/dl.

By six months of age, hemoglobin runs By six months of age, hemoglobin runs between 11 and 14 g/dl. between 11 and 14 g/dl.

Between 1 year and 15 years of age Between 1 year and 15 years of age hemoglobin runs between 11-15 g/dl. hemoglobin runs between 11-15 g/dl.

Normal adult hemoglobin depends on Normal adult hemoglobin depends on gender: gender:

♀♀ 12-16 g/dl12-16 g/dl ♂♂ 14-18 g/dl14-18 g/dl

In geriatric age group, men and women In geriatric age group, men and women have same hemoglobin range:  12-16 g/dl. have same hemoglobin range:  12-16 g/dl.

Anemia Anemia

A reduction in RBC volume or Hb concentration A reduction in RBC volume or Hb concentration

below the range of values occurring in healthy below the range of values occurring in healthy

personperson

Although a reduction in the amount of circulating Hb Although a reduction in the amount of circulating Hb

decreases the oxygen carrying capacity of the blood decreases the oxygen carrying capacity of the blood

few clinical disturbances occur until Hb levels fall few clinical disturbances occur until Hb levels fall

below 7-8gr/dlbelow 7-8gr/dl

Below this level pallor becomes evident in the skin and Below this level pallor becomes evident in the skin and

mucous membranesmucous membranes

Physiologic adjustments to Physiologic adjustments to anemiaanemia

Increased cardiac outputIncreased cardiac output Increased oxygen extractionIncreased oxygen extraction Shunting of blood flow toward vital organs Shunting of blood flow toward vital organs

and tissuesand tissues In addition the concentration of 2,3 DPG In addition the concentration of 2,3 DPG

increasesincreases Shift to the right of oxygen dissociation curve, Shift to the right of oxygen dissociation curve,

reducing the affinity of Hb for oxygenreducing the affinity of Hb for oxygen results in more complete transfer of oxygen to the tissuesresults in more complete transfer of oxygen to the tissues

Anemia can be defined as a Anemia can be defined as a reduction in the hemoglobin, reduction in the hemoglobin, hematocrit or red cell numberhematocrit or red cell number

The pathophysiologic effects of The pathophysiologic effects of anemia depend upon the rate at anemia depend upon the rate at which the anemia progresseswhich the anemia progresses

In an acute hemorhage In an acute hemorhage the arterial pressure falls, cardiac output the arterial pressure falls, cardiac output

decreases, peripheral vasculature decreases, peripheral vasculature

collapses and the patient rapidly enters collapses and the patient rapidly enters

hypovolemic shockhypovolemic shock The sudden rapid loss of 30% of the total The sudden rapid loss of 30% of the total

blood volume often results in death unless blood volume often results in death unless

there is immediate medical interventionthere is immediate medical intervention

In a slowly developing anemia In a slowly developing anemia cardiac output increases, blood shunted cardiac output increases, blood shunted

from nonvital organs and hemoglobin from nonvital organs and hemoglobin

oxygen affinity decreases due to increased oxygen affinity decreases due to increased

levels of 2,3 DPG.levels of 2,3 DPG.

Total blood volume remains remarkably Total blood volume remains remarkably

constant. More than 50% of the red cell constant. More than 50% of the red cell

mass can be lost slowly with minimal mass can be lost slowly with minimal

effectseffects

It must be remembered that anemia is It must be remembered that anemia is not a disease rather it’s a sign of not a disease rather it’s a sign of diseasedisease

The clinical effects (lack of oxygen) The clinical effects (lack of oxygen) includeinclude Tiredness, lassitude, weakness, pallorTiredness, lassitude, weakness, pallor Dyspnea and anginal pain are not Dyspnea and anginal pain are not

uncommon after exerciseuncommon after exercise Jaundice may occur in some anemiasJaundice may occur in some anemias

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Classification of AnemiasClassification of Anemias

Have a variety of ways - depending Have a variety of ways - depending on criteria used: on criteria used: FunctionalFunctional MorphologicalMorphological Clinical Clinical QuantitativeQuantitative

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Functional Functional Classification of AnemiasClassification of Anemias

Decreased RBC production Decreased RBC production (hypoproliferative) (hypoproliferative) Defective hemoglobin synthesisDefective hemoglobin synthesis

Fe deficiencyFe deficiency B12 deficiencyB12 deficiency Folate deficiencyFolate deficiency

Impaired bone marrow or stem cell function, as Impaired bone marrow or stem cell function, as in leukemiain leukemia

Increased RBC destruction, as in sickle cell Increased RBC destruction, as in sickle cell anemia or hemolytic anemiaanemia or hemolytic anemia

Combination of the two (sometimes called Combination of the two (sometimes called “ineffective erythropoiesis”) “ineffective erythropoiesis”)

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Morphological Morphological Classification of AnemiasClassification of Anemias

Morphological based on sizes and Morphological based on sizes and color of RBCs color of RBCs Normochromic Normochromic Normocytic Normocytic HypochromicHypochromic Microcytic Microcytic NormochromicNormochromic Microcytic Microcytic NormochromicNormochromic MacrocyticMacrocytic

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Clinical Clinical Classification of AnemiasClassification of Anemias

According to their associated causes:According to their associated causes: Blood loss Blood loss Iron deficiency Iron deficiency HemolysisHemolysis InfectionInfection Nutritional deficiencyNutritional deficiency Metastatic bone marrow replacementMetastatic bone marrow replacement

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QuantitativeQuantitativeClassification of AnemiasClassification of Anemias

Quantitatively by: Quantitatively by: HematocritHematocrit Hemoglobin Hemoglobin Blood cell indices Blood cell indices Reticulocyte count Reticulocyte count

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Hemoglobin and Hemoglobin and Hematocrit Hematocrit 1 of 21 of 2

Anemia usually diagnosed on either Anemia usually diagnosed on either hemoglobin or hematocrit values. hemoglobin or hematocrit values.

Remember, normal ranges vary depending Remember, normal ranges vary depending on age, gender, state of hydration, patient on age, gender, state of hydration, patient positioning and local patient population. positioning and local patient population.

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Hemoglobin and Hemoglobin and Hematocrit Hematocrit 2 of 22 of 2

On basis of H&H, anemia can be classified as mild, On basis of H&H, anemia can be classified as mild, moderate, or severe.moderate, or severe.

On basis of duration of onset, anemia can be On basis of duration of onset, anemia can be classified as either chronic or acute. classified as either chronic or acute.

Rules of Three: Rules of Three: RBC X 3 = HemoglobinRBC X 3 = Hemoglobin Hemoglobin X 3 = HematocritHemoglobin X 3 = Hematocrit

Ratio of Hb and Hct will vary with cause of anemia Ratio of Hb and Hct will vary with cause of anemia and affect the RBC indices, particularly the MCV and affect the RBC indices, particularly the MCV (Mean Corpuscular Volume). (Mean Corpuscular Volume).

Microscopic examination of peripheral blood smear Microscopic examination of peripheral blood smear is required for evaluation of anemia.  Bone marrow is required for evaluation of anemia.  Bone marrow aspirates and smear evaluation may also be aspirates and smear evaluation may also be needed. needed.

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RBC IndicesRBC Indices

RBC indices include: RBC indices include: Mean Corpuscular Volume (MCV) Mean Corpuscular Hemoglobin (MCH) Mean Corpuscular Hemoglobin

Concentration (MCHC) RBC Distribution Width (RDW)

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MCVMCV

Mean cell volumeMean cell volume MCV is average size of RBCMCV is average size of RBC MCV = MCV = Hct x 10 Hct x 10

RBC (millions) RBC (millions) If 80-100 fL, normal range, RBCs If 80-100 fL, normal range, RBCs

considered considered normocyticnormocytic If < 80 fL are If < 80 fL are microcyticmicrocytic If > 100 fL are If > 100 fL are macrocyticmacrocytic Not reliable when have marked anisocytosisNot reliable when have marked anisocytosis

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MCHMCH

MCH is average weight of MCH is average weight of hemoglobin per RBC. hemoglobin per RBC.

MCH = MCH = Hgb x 10 Hgb x 10

RBC (millions) RBC (millions)

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MCHCMCHC MCHC is average hemoglobin MCHC is average hemoglobin

concentration per RBC concentration per RBC MCHC = MCHC = Hgb x 100 Hgb x 100

Hct (%) Hct (%) If MCHC is normal, cell described as If MCHC is normal, cell described as

normochromicnormochromic If MCHC is less than normal, cell If MCHC is less than normal, cell

described as described as hypochromichypochromic There are no There are no hyperchromichyperchromic RBCs RBCs

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RDWRDW

Most automated instruments now Most automated instruments now provide an provide an RBC Distribution WidthRBC Distribution Width (RDW)(RDW)

An index of RBC size variationAn index of RBC size variation May be used to quantitate the amount May be used to quantitate the amount

of anisocytosis on peripheral blood of anisocytosis on peripheral blood smearsmear

Normal range is 11.5% to 14.5% for Normal range is 11.5% to 14.5% for both men and women both men and women

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RBC Indices and Other RBC Indices and Other TestsTests

RBC indices are automatically calculated by RBC indices are automatically calculated by instruments. instruments.

Microscopic evaluation will determine if RBCs Microscopic evaluation will determine if RBCs are normocytic, microcytic, or macrocytic and are normocytic, microcytic, or macrocytic and normochromic or hypochromic. normochromic or hypochromic.

Use of RBC indices in differential diagnosis can Use of RBC indices in differential diagnosis can provide picture of what is occurring clinically. provide picture of what is occurring clinically.

If anemia caused be bone marrow failure, If anemia caused be bone marrow failure, requires information about RBC production. requires information about RBC production. Information obtained from reticulocyte count. Information obtained from reticulocyte count. Reticulocyte count measures effective RBC Reticulocyte count measures effective RBC production. production.

As study different anemias, will learn As study different anemias, will learn morphology. morphology.

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Treatment of AnemiasTreatment of Anemias

Treated according to cause; Should Treated according to cause; Should know cause before beginning know cause before beginning treatment. treatment.

Patient can have more than one cause Patient can have more than one cause of anemia. of anemia.

Must use diagnostic tests to determine Must use diagnostic tests to determine cause(s). cause(s).

Do diagnostic tests Do diagnostic tests beforebefore transfusions, transfusions, because transfusions obscure and because transfusions obscure and confuse findings.confuse findings.

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Hgb Hgb (In the Diagnosis of (In the Diagnosis of

Anemia)Anemia)

Hbg is the main component of RBCs Hbg is the main component of RBCs and carries oxygen to tissues. and carries oxygen to tissues.

Three methods to measure Three methods to measure hemoglobin: hemoglobin:

Cyanmethemoglobin (recommended Cyanmethemoglobin (recommended method)method)

Oxyhemoglobin Oxyhemoglobin Iron Content  Iron Content 

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Hct Hct (In the Diagnosis of (In the Diagnosis of

Anemia) Anemia) 1 of 31 of 3

Is packed RBC volume Is packed RBC volume Is ratio of RBC volume to volume of whole Is ratio of RBC volume to volume of whole

bloodblood Usually expressed in percentage (42%) or Usually expressed in percentage (42%) or

as decimal fraction (.42)as decimal fraction (.42) Venous and arterial hematocrits closely Venous and arterial hematocrits closely

agree agree Specimen of choice is EDTA Specimen of choice is EDTA

(ethylenediaminetetra acetic acid), oxalate (ethylenediaminetetra acetic acid), oxalate or heparin or heparin

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Hct Hct (In the Diagnosis of (In the Diagnosis of

Anemia) Anemia) 2 of 32 of 3

Measurement done by centrifugation or through calculations performed on many automated measurements.

Calculated hematocrit is product of MCV and RBC count.

Normal ranges are 42-52% in men and 37-47% in women.

Normal ranges also vary among age groups, institutions, and geographic locations.

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RBC Indices RBC Indices (In the Diagnosis of (In the Diagnosis of

Anemia) Anemia) 1 of 21 of 2

RBC indices are readily available RBC indices are readily available from the automated hematology from the automated hematology counting devicescounting devices

MCV is measured directly or MCV is measured directly or calculated from hematocrit and RBC calculated from hematocrit and RBC count; MCH and MCHC are both count; MCH and MCHC are both calculated calculated

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RBC Indices RBC Indices (In the Diagnosis of (In the Diagnosis of

Anemia) Anemia) 2 of 22 of 2

In various anemic states, indices may In various anemic states, indices may be altered: be altered:

Microcytic Anemia: Microcytic Anemia: MCV usually 50-80 fL MCV usually 50-80 fL MCH usually 15-25 pg MCH usually 15-25 pg MCHC usually 22-30% MCHC usually 22-30%

Macrocytic Anemia:Macrocytic Anemia: MCV usually 100-120 fL MCV usually 100-120 fL

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Peripheral Blood Smear Peripheral Blood Smear (In the Diagnosis of (In the Diagnosis of

Anemia)Anemia) Very useful in diagnosing and Very useful in diagnosing and

classifying anemias classifying anemias Look for: Look for:

NeutropeniaNeutropenia ThrombocytopeniaThrombocytopenia HypochromiaHypochromia Size and shape of RBCs Size and shape of RBCs Unusual leukocytes (hypersegmentation) Unusual leukocytes (hypersegmentation) Red cell inclusions: basophilic stippling, Red cell inclusions: basophilic stippling,

Howell-Jolly bodies…Howell-Jolly bodies…

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Reticulocyte Count Reticulocyte Count (In the Diagnosis of (In the Diagnosis of

Anemia)Anemia) Useful in determining response and potential Useful in determining response and potential

of bone marrow. of bone marrow. Reticulocytes are non-nucleated RBCs that Reticulocytes are non-nucleated RBCs that

still contain RNA. still contain RNA. Visualized by staining with supravital dyes, Visualized by staining with supravital dyes,

including new methylene blue or brilliant including new methylene blue or brilliant cresyl blue; RNA is precipitated as dye-cresyl blue; RNA is precipitated as dye-protein complex. protein complex.

Normal range is 0.5-2.0% of all erythrocytes. Normal range is 0.5-2.0% of all erythrocytes. If bone marrow responding to anemia, should If bone marrow responding to anemia, should

see increases in retic count. see increases in retic count. Newborns have higher retic count than Newborns have higher retic count than

adults until second or third week of life. adults until second or third week of life.

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Bone Marrow Bone Marrow (In the Diagnosis of (In the Diagnosis of

Anemia)Anemia)

Bone marrow aspiration and biopsy Bone marrow aspiration and biopsy are important diagnostic tools in are important diagnostic tools in the determination of anemia.the determination of anemia.

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Other Tests Other Tests (In the Diagnosis of (In the Diagnosis of

Anemia)Anemia) Hemoglobin Electrophoresis Hemoglobin Electrophoresis Antiglobulin Testing Antiglobulin Testing Osmotic Fragility Osmotic Fragility Sugar Water Test Sugar Water Test Ham’s Test Ham’s Test RBC Enzymes RBC Enzymes B12, Fe, TIBC, Folate Levels B12, Fe, TIBC, Folate Levels

Anemia is usually classified Anemia is usually classified

according to according to EtiologyEtiology

PathophysiologyPathophysiology

Morphology Morphology

Laboratory diagnosisLaboratory diagnosis

Initial investigation and tentative diagnosis is Initial investigation and tentative diagnosis is

made with a relatively small number of testsmade with a relatively small number of tests The precise diagnosis is made with further The precise diagnosis is made with further

special testsspecial tests Screening is usually done with CBC Screening is usually done with CBC

(complete blood count) (complete blood count) The exact procedures in a CBC depends The exact procedures in a CBC depends

upon the instrumentation in the laboratory upon the instrumentation in the laboratory

Most laboratories now use automated Most laboratories now use automated multiparameter instruments. These are multiparameter instruments. These are Hb(hemoglobin)Hb(hemoglobin) RBCRBC MCVMCV Htc(hematocrit)Htc(hematocrit) MCHMCH MCHCMCHC RDWRDW WBCWBC Platelet and MPVPlatelet and MPV

Directly measured values

Calculated values

MCV:MCV:

MCH:MCH:

MCHC:MCHC:

Htc X10

RBC(90±7 fl)

Hb X100

RBC(30±3)

Hb X100

Htc

(33±2)

spherocytosiseliptocytosis

poikilocytosis

stomatocytosis

acanthocytosis Fragmentation

hemolysis

Sickle cell anemia; target cells and sickled cells

Normal RBC

Target cellsHeinz body anemia

Thalassemia; severe hypochromia

Anisopoikilocytosis, target cells

normal macrocytes

Hypochromic, microcytes

Target cells

schistocytes