Hematology: Anemia I

Front 1

What is anemia?

Back 1

- "Without blood"- reduced number of RBCs, Hb, and/or Hct.
- Decreased oxygen delivery.

- Not a dz; manifestation of numerous other underlying processes.
- Most common manifestation of dz worldwide.

Front 2

Hb Reference Value

Back 2

Female: 12.0-15.0 g/dL
Male: 14.0-18.0 g/dL

Front 3

Hct Reference Value

Back 3

Female: 35-49%
Male: 40-54%

Front 4

RBC Reference Value

Back 4

Female: 4.00-5.40 X 10^6/uL
Male: 4.60-6.00 X 10^6/uL

Front 5

Stable RBC mass

Back 5

1% of RBCs must be replaced daily
BM must produce ~50,000 retics/uL each day

Front 6

Clinical Dx of Anemia.

Back 6

Patient hx.
Physical examination
Signs/symptoms
Hematologic values
Other lab procedures

Front 7

Classic symptoms of anemia

Back 7

Fatigue
Shortness of breath (decreased oxygen delivery)
Tachychardia: increased heart rate (severe anemia)
Hypotension: decreased BP (severe anemia)

Front 8

Factors that reflect the fall of Hb conc'n.

Back 8

Decreased oxygen delivery to tissues
Hypovolemia (acute and marked bleeding)

Front 9

Physiological adaptations.

Back 9

Increased EPO secretion by the kidneys.

Tissue hypoxia--> increased 2,3 BPG (oxygen dissociation curve shift to the reight- decreased oxygen delivery)--> inc. oxygen delivery to the tissues & inc. oxygen utilization by tissues.

Front 10

What does hematology analyzer can determine?

Back 10

RBC count
Hb/Hct
RBC indices

Front 11

RBC indices

Back 11

Mean Cell Volume (MCV)
Mean Cell Hb (MCH)
Mean Cell Hb Conc'n (MCHC)

Front 12

MCV

Back 12

Normal reference range: 80-100fL
Most important of the RBC indices

Front 13

RBC distribution width (RDW)

Back 13

Mathematical expression of variability within the volume distribution of the RBC population.

Front 14

Anisocytosis

Back 14

Indicates variation of RBC size.

Front 15

Reticulocyte count

Back 15

Indicate shortened survival
Appropriate response by the BM to increase RBC production.
Contain residual RNA
Refe. range (adult): 0.5-1.5%

Front 16

How to determine retic count?

Back 16

RBC count X retic %

Front 17

How to correct retic for anemia?

Back 17

% retic X patient's Hct/44
Result of a normal Hct

Front 18

Reticulocyte production index (RPI)

Back 18

Formula: Corrected retic count/maturation time
1 day= Hct of 45%
1.5 days= Hct 35%
2 days= Hct 25%
2.5 days= Hct 15%

Front 19

What is the expected RPI in anemic patient?

Back 19

>2

Front 20

What is the expected retic count in hemolytic anemia?

Back 20

Appropriately elevated

Front 21

Expected retic count in decreased RBC production.

Back 21

Often decreased or inappropriately low.

Front 22

Importance of retic count?

Back 22

Helps divide anemias into decreased production or shortened RBC survival.

Front 23

Blood smear examination.

Back 23

Necessary for anemia evaluation (variations in size, shape, color, content, inclusions)
Serves as QC to verify results from automated analyzer.

Front 24

RBC life span?

Back 24

120 days
Healthy individual: ~1% of "old" RBC lost daily; replaced by BM.

Front 25

Nutritional factors required for adequate RBC production.

Back 25

Iron
Vit. B12
Folic acid

Front 26

What is erythropoeisis?

Back 26

Marrow erythroid proliferation.
Occurs ony in BM (adult)

Front 27

Effective erythropoeisis

Back 27

BM is able to produce functional RBCs that leave the marrow & supply the blood with adequate number of cells= NO ANEMIA

Front 28

Ineffective erythropoesis

Back 28

Production of progenitor cells that are defective--> reduced number of functional RBCs (ANEMIA).
Destroyed before leaving the BM
Megaloblastic anemia, Thalassemia, Sideroblastic anemia

Front 29

Insufficient erythropoesis

Back 29

Quantitative lack of erythroid precursors in the marrow.
Anemia due to dec. in total RBC production
Fe Deficiency, EPO deficiency, Aplastic anemia, Viral infection, Suppression of RBC precursor due to marrow infiltration (tumor, leukemia)

Front 30

Approaches to ID the cause of anemia

Back 30

Kinetic approach: address mechanism(s) responsible for the fall of Hb.

Morphologic Approach: categorizing anemias via alterations in RBC size & retic response.

Front 31

Causes of anemia

Back 31

Decreased RBC production
Increased RBC destruction
Blood loss

** May co-exist with BM suppression**

Front 32

Causes of reduced RBC production

Back 32

DNA synthesis (megaloblastic anemia
HSC proliferation (aplastic anemia)
Hb synthesis: Fe deficiency
BM suppression (chemo)

Front 33

RBC life span <100 days

Back 33

Hemolysis may not be anemia

Front 34

Hemolytic anemia

Back 34

Develops when BM unable to keep up with the need to replace >5% of the RBC mass/day, corresponding to a RNC survival of about 20 days.

Front 35

Causes of increased RBC destruction (INtravascular abnormalities)

Back 35

Membrane defects (H. spherocytosis)
Enzyme deficiency (G6PD)
Globin Defects(Hemoglobinopathies)
PNH (cell surface protein deficiency)

Front 36

Increased RBC destruction/loss (extravascular abnormalities)

Back 36

Mechanical (MAHA- TTP, HUS)
Infection (malaria, babesia)
Chemical/physical agents (burns, drugs)
Immune mediated (transfusion)

Front 37

Blood loss (most common cause of anemia)--> loss of iron contained in these cells--> iron deficiency

Back 37

Occult bleeding (ulcer, GI bleed, carcinoma)
Obvious bleeding (trauma, menorrhagia)

Front 38

Useful tests for evaluation of anemia

Back 38

CBC
RNC indices (esp. MCV)
RDW
Peripheral blood smear
Reticulocyte count

Front 39

Microcytes

Back 39

<6um in diameter
MCV < 80fL

Front 40

Macrocytes

Back 40

>8um in diameter
MCV > 100fL

Front 41

Hypochromic

Back 41

MCHC < 32 g/dL

Front 42

Hyperchromic

Back 42

MCHC > 36 g/dL

Front 43

Microcytic anemia

Back 43

Caused by conditions that result in Hb synthesis reduction
Reduced Fe availability, reduced heme synthesis, reduced globin production

Front 44

Microcytic anemia: possible pathology

Back 44

Fe deficiency (most common cause)
Thalassemia (deficiency in globin synthesis)
Sideroblastic anemia (heme synthesis deficiency)
Anemia of chronic dz (inability to use iron)
Lead poisoning (heme synthesis deficiency)

Front 45

Types of anemia

Back 45

Microcytic/Hypochromic anemia
Macrocytic/Normochromic anemia
Normocytic/Normochromic anemia

Front 46

Microcytic/Hypochromic anemia

Back 46

MCV is less than 80 fL
MCHC is less than 32 g/dL(reference range = 32 – 36 g/dL)
Small RBCs with increased central pallor

Front 47

Macrocytic/Normochromic Anemias

Back 47

MCV greater than 100 fL and MCHC within reference range (32 – 36 g/dL)
RBCs appear macrocytic
May be megaloblastic or non-megaloblastic

Front 48

Megaloblastic Anemias

Back 48

Interefere DNA synthesis
Asynchronous maturation
Vitamin B12/folate deficiency; myelodysplasia (MDS)
Oval macrocytes, large nRBC precursors, hypersegmented neutrophils
MCV > 115fL

Front 49

Non- Megaloblastic Anemias

Back 49

Round macrocytes
Related to membrane changes (disrupting cholesterol:PL ratio)
Seen in chronic liver dz
Rare MCV > 115fL

Front 50

Artifactual cause of megaloblastic anemia

Back 50

Agglutination

Front 51

Normocytic/Normochromic Anemias

Back 51

MCV of 80 – 100 fL
MCHC of 32 – 36 g/dL
Renal dz (reduced EPO), aplastic anemia, splenomegaly, infections.

Front 52

What does increased retic count mean?

Back 52

BM trying to compensate by increasing production of RBCs
Most often elevated in hemolytic anemia

Front 53

RDW relationship to types of anemia

Back 53

MCV low; RDW normal (microcytic; homogeneous)
Thalassemia

MCV low; RDW high (microcytic; heterogeneous)
Fe deficiency

MCV high; RDW high (macrocytic; heterogeneous)
Vitamin B12/folate deficiency

MCV normal; RDW high (normocytic; heterogenous
Anemic hemoglobinopathy (sickle cell anemia)