Download Quiz Yourself

Quiz Yourself
Hematology
Please note that this was put together by a UNC MS2
for other UNC MS2s. If you find any mistakes or have
any feedback, let us know – especially if this was
remotely helpful in any way!
Characteristics of
Normal Adult Bone Marrow
•Consists of approximately 50% fat cells;
•Has more myeloid cells than erythroid cells
(myeloid:erythroid ratio 2:1 to 7:1)
•Megakaryocytes are 2-5 per high power field
•Plasma cells <3%
•Lymphocytes <20%
Peripheral Blood Morphology
1.
2.
Erythrocytes
Granulocytes
1.
2.
3.
3.
4.
5.
Neutrophils
Eosinophils
Basophils
Platelets
Monocytes
Lymphocytes (B & T cells)
Erythropoiesis – what is the order?
Proerythroblast Basophilic
erythroblast
Orthochromatophilic
erythroblast
Reticulocyte
Polychromatophilic
erythroblast
Mature RBC
Granulopoiesis – what is the order?
Myeloblast
Metamyelocyte
Promyelocyte
Band
Myelocyte*
Neutrophil
Identify the Type of Cell
Basophil
Eosinophil
Monocyte
Neutrophil
Anemia: When do you give
a transfusion right away?
.Angina pectoris – coronary
insufficiency
.Shock
.Surgery
Iron kinetics as a function of time



1. Childhood – building both the hemoglobin and
storage iron by the intake and conservation of
iron- years
2. Adolescent and adult males – full complement
of hemoglobin and storage iron
3. Adolescent and adult females – iron content is
challenged by menses and childbirth
Causes of iron deficiency
1.
2.
3.
4.
inadequate intake
Malabsorption
diversion of iron during pregnancy
blood loss
RBC Characteristics in Iron
Deficiency Anemia?


Microcytic – small RBCs
Hypochromatic – pale RBCs
Ways to diagnose iron
deficiency anemia?
1)
Serum ferritin – will be decreased.
2)
3)
Bone Marrow - staining
Treatment – the simplest!
Careful, it’ll also be low in diseased/ill
patients (an acute phase reactant)
Causes of Macrocytic Anemia


B12 deficiency
Folate deficiency
Uses of B12 & Folate

DNA synthesis


B12 = co-factor
Folate = transfer single carbon groups
How do we get folate and B12?

Folate




In leafy green veggies, liver, yeast
Destroyed by cooking
Need 100-200 micrograms daily
Vitamin B12



In animal products
Unaffected by cooking
Need 1-2 micrograms daily
Folate Deficiency –
3 major causes
Dietary
Malabsorption
Increased usage
3 ways to diagnose
folate deficiency
Morphology – macrocytic RBCs and
hypersegmented neutrophils
Serum folate
Red cell folate
What’s This?
Megaloblastic Anemia
Possible Causes?
B12 or folate deficiency
B12 Deficiency –
3 major causes
Pernicious Anemia
Pancreatic Insufficiency
Malabsorption
3 ways to diagnose
B12 deficiency
Morphology
Serum B12
Neurologic findings – Demyelination
of spinal cord, cerebral cortex
Treating B12 & Folate Deficiencies

B12


IM B12 supplementation for life
Folate

Daily folate supplement (1mg/day)
What do you see in the RBCs below?
How would we quantitate this?


Anisocytosis refers to
red cells which vary
widely in size.
The RDW
mathematically
measures the range
of red cell sizes.
What do you see in the RBCs below?
What diseases might they be
associated with?



Microcytosis refers to red
cells that are small.
You can use the
lymphocyte nucleus as a
visual reference, or you
can use the MCV
Associated with



Iron deficiency
Thalassemias
Sideroblastic anemia
What do you see in
the top slide?
Characterizes what
diseases?


Macrocytosis refers to large
red cells.
Associated with






Elevated reticulocyte count
B12/folate deficiency
Liver disease
Thyroid disease
Chemotherapy
Anti-retrovirals (AZT)
What’s wrong with these RBCs?
Measured how? A likely cause?




Hypochromasia refers
to red cells that have
too little hemoglobin.
The area of central
pallor is more than 1/3
the total red cell
diameter.
This is measured by
the MCH (mean
cellular hemoglobin)
Iron deficiency
What do you see on this slide?


Poikilocytosis refers to
red cells that vary
widely in shape.
Remember that
anisocytosis refers to
red cells that vary
widely in size.
What do you see here?
Diseases?


Target cells look like
bulls-eyes.
Associated with




Liver disease
Thalassemias
Hemoglobin C
After splenectomy
What do you see here?
Diseases?


Spherocytes have a loss
of central pallor.
Can be seen in



Hereditary spherocytosis
Autoimmune hemolysis
If due to autoimmune
hemolysis, the cells are
smaller (i.e.
microspherocytes)
What do you see here?
Diseases?


Schistocytes are red
cell fragments with
sharp edges.
They are a hallmark
of Microangiopathic
Hemolytic Anemia
(MAHA)
What do you see here?


Sickle Cells are seen
in sickle cell anemia.
Notice that this slide
has target cells as
well as a sickled cell.
What RBCs are here?
How do you
distinguish the two?
Associated disease?


Echinocytes, or burr cells,
have small, regular
projections. Seen in renal
disease
Acanthocytes, or spur
cells, have larger, irregular
projections, and are seen
in liver disease.
What do you see here?
What causes it?



Teardrop cells
Seen in myelophthisic
processes, or diseases
of marrow infiltration.
Deformed as it tries
to squeeze out of the
bone marrow
And what
have we
here? What
causes
them?


Howell-Jolly bodies are peripheral, small,
round, purple inclusions within red cells that
represent nuclear remnants.
They are seen after splenectomy, or in cases of
splenic hypofunction.
What do you see
here? Causes?



Rouleaux are linear arrangements of red cells typically
described as “piles of coins on a plate”
They are typically seen in disorders with increased
levels of immunoglobulin, such as Multiple Myeloma or
Waldenstrom’s macroglobulinemia.
Severe hypo-albuminemia can also lead to reouleux
formation
What do you
see here?


Red cell agglutination occurs when the red cells
are coated with IgM. IgM is large enough to
bridge two red cells and cause agglutination.
Unlike rouleaux, the red cell clumps are not
orderly and linear.
General Clinical Features of
Hemolytic Anemias






Splenomegaly is generally present
Patients have an increased incidence of pigmented
gallstones.
Dark urine (tea-colored or red), jaundice, scleral
icterus
Patients may have chronic ankle ulcers.
Aplastic crises associated with Parvovirus B19, may
occur
Increased requirement for folate
Post-splenectomy blood findings


Howell-Jolly bodies - small round blue DNA
remnants in periphery of RBCs
Red cell abnormalities: target cells,
acanthocytes, schistocytes, NRBCs
Hemolytic Anemias Sites of Red Cell Destruction

Extravascular Hemolysis 

Macrophages in spleen, liver, and marrow remove
damaged or antibody-coated red cells
Intravascular Hemolysis

Red cells rupture within the vasculature, releasing
free hemoglobin into the circulation
(and the
circulation does NOT like this!)
Evidence for increased red
cell production



In the blood:
 Elevated reticulocyte count
 May be associated with high MCV
 Circulating NRBCs may be present
In the bone marrow:
 erythroid hyperplasia
 reduced M/E (myeloid/erythroid) ratio
In the bone:
 Deforming changes in the skull and long bones
(“frontal bossing”)
Evidence for Increased Red Cell
Destruction

Biochemical consequences of hemolysis in general







Morphologic evidence of red cell damage




Elevated LDH
Elevated unconjugated bilirubin  jaundice, scleral icterus
Lower serum haptoglobin
Hemoglobinemia
Hemoglobinuria
Hemosiderinuria
Schistocytes
Spherocytes
Bite/blister cells
Reduced red cell life-span
Hemolytic Anemias Classification by Etiology

Congenital




Defects in membrane skeleton proteins
Defects in enzymes involved in energy production
Hemoglobin defects
Acquired


Immune-mediated
Non-immune-mediated

Most common defect leading to anemia?


Frequency?



Defect is in proteins of the membrane skeleton, usually spectrin or
ankyrin
Lipid microvesicles are pinched off in the spleen and other RE
organs, causing decreased MCV and spherocytic change.
Diagnosing?


Autosomal dominant
Pathophysiology?


Affects 1/5000 Europeans
Transmission?


Hereditary spherocytosis
Increased osmotic fragility
Treatment?


Supplemental folate
Splenectomy (but carefully consider timing in children)
• Functions of GP6D?
•
•
Detoxification of metabolites of oxidative stress
Elimination of methemoglobin
•
•
NADPH
Reduced glutathione
•
•
Heinz bodies
Causes the formation of bite/blister cells
•
•
•
•
•
Type B is more prevalent
Type A is in 20% of healthy Africans
In 10-14% of African American men
Also prevalent in the Mediterranean
X-linked
• Important Products of GP6D?
• Diagnostic methemoglobin precipitate?
• Epidemiology of GP6D Deficiency?
G6PD Deficiency
Agents to avoid
For SKAND…
–
–
–
–
–
–
Fava beans
Sulfa drugs
Vitamin K
Anti-malarials
Naphtha
compounds
(mothballs)
Dapsone
What cell is below?
Blister cell
Sorry Skand – at least your girlfriend thought it was funny!
How will you diagnose
an autoimmune cause
of hemolytic anemia?
Coomb’s Test


The Direct Coomb’s = DAT (Direct
Antiglobulin Test) - tests for IgG or C3
DIRECTLY ON THE RED CELLS. You’re
adding patient RBCs!
The Indirect Coomb’s - tests for IgG or C3
in the serum which react with generic
normal red cells. This is also known as
the antibody screen in blood-banking.
You’re adding patient serum!
Warm-Antibody Hemolytic Anemias
Clinical Features



Splenomegaly, jaundice usually present.
Depending on degree of anemia and rate of fall in
hemoglobin, patients can have VERY symptomatic
anemia
Lab Dx  reticulocytes,  bili,  LDH,
 positive Coomb’s test - both direct and indirect.
 SPHEROCYTES are seen on the peripheral smear.
Warm-Antibody Hemolytic Anemias
Treatment

Immunosuppressive Treatment





First line is corticosteroids (i.e. prednisone).
If steroids fail to work, or if patient relapses after steroid
taper, splenectomy may be necessary.
Immunosuppressives such as cyclophosphamide (Cytoxan)
or azathioprine (Immuran) may be required as third-line
therapy.
Folate repletion
Transfusion – determining factors:


Heart failure, shock?
Inadequate reticulocyte count?
Drug-Induced Immune Hemolysis
Three general mechanisms

Innocent bystander




Hapten



the Ab was directed at the drug, but it cross reacted w/
RBCs
Drug must be present for hemolysis to occur
Quinine, Quinidine, Isoniazide
Drug binding to RBC  Abs that react to this complex
Penicillins, Cephalosporins
True autoimmune


You don’t need the drug in the body any more to get the
hemolysis
Alpha-methyldopa, L-DOPA, Procainamide
Cold Agglutinin Disease







IgM antibodies bind to I antigens of RBCs when cold
(falls off when warm)
Causes agglutination  cyanosis & ischemia of
extremities
Direct Coomb’s test + for C3, but not IgM!
Has both intravascular and extravascular hemolytic
components
Primary, or associated w/ Mycoplasma, Mononucleosis,
or lymphoproliferative disease
Treat by avoiding cold & folate repletion
Corticosteroid and splenectomies uneffective (big
difference from warm antibody-mediated hemolysis)
Non-Immune Hemolytic Anemia
Classification

Mechanical trauma to red cells





Microangiopathic Hemolytic Anemia
Abnormalities in heart and large vessels
March Hemoglobinuria
Infections
Drugs, Chemicals, and Venoms
Chemical & Physical Agents
Causing Hemolysis
“BAr CoIns”




Severe Burns
Arsenic
Copper
Insect and spider bites
Infections Causing Hemolysis




Malaroa
Babesia microti
Clostridium welchii
Bartonella bacilliformis
Basic Structure of All
Human Hemoglobin

Each hemoglobin molecule is composed of:


4 iron-containing, tetrapyrrole heme rings
4 polypeptide globin chains


2 alpha chains
2 non-alpha chains

Each  globin chain has 141 amino acids

All non- chains have 146 amino acids

There is considerable structural homology
among the non-alpha chains
Normal Human Hemoglobins

Gower Hemoglobin (Embryonic)


Fetal Hemoglobin (HbF)


22
Major Adult Hemoglobin (HbA)


2ε2
22
Minor Adult Hemoglobin (HbA2)

22
Heme Synthesis

Begins with condensation of glycine & succinyl CoA  -amino levulinic acid (-ALA).






The rate-limiting step in heme synthesis
Requires intra-mitochondrial enzyme ALAsynthase
-ALA travels to cytoplasm; converted to
porphobilinogen (PBG), a monopyrrole.
PBG converted from monopyrrole to biologically
active form protoporphyrin IX, a tetrapyrrole.
Iron inserted into tetrapyrrole ring n the
mitochondria
Heme synthesis stimulated by iron & repressed
when iron is inadequate (e.g., iron deficiency)
Location of the Globin Genes
•
Genes for the non- chains are located on
Chromosome 11. This is referred to as the globin gene cluster
•
 Chain genes are located on Chromosome 16
•
There is duplication of the genes for:
•
•
 Globin
 Globin (G and A) *
•
•
G
and A differ from one another only at position 136
where they have glycine & alanine respectively
Synthesis of the non- chains involves a
coordinated switching that proceeds from
embryonic (ε) to fetal () to adult () globin
chains
•
Yolk sac (ε)  liver/spleen ()  marrow ()
Structure of the Hemoglobin
Molecule






Each Hb is comprised of 4 subunits: 2 identical  chains & 2
identical non- chains
Each chain is arranged in the form of an -helix with 8
individual helical segments (labeled A - H)
Each globin molecule has both hydrophobic & hydrophilic
areas
The iron-containing heme ring is buried within a very
hydrophobic region of the globin that is called the “Heme
Pocket”
The hydrophobic nature of this region protects the iron
residue from oxidation, thereby maintaining it in the active,
reduced form
Each iron atom in the center of the heme residue is held in
place and kept in the active, reduced Fe++ state by two
histidine residues
Possible Consequences of a
Hemoglobinopathy

No detectable effect

Instability of the hemoglobin molecule



An increase or a decrease in oxygen
affinity
Inability to maintain the heme iron in
its active, reduced state
(methemoglobinemia)
Decreased solubility of the hemoglobin
molecule
Unstable
Hemoglobinopathies




Most of the unstable hemoglobinopathies
involve a mutation in the region of the heme
pocket
These mutations enable water to gain access to
this very hydrophobic region of the molecule
The end result is heme instability, denaturation,
and release of heme from its binding site
The demonstration of Heinz Bodies in these red
cells is evidence of the presence of an unstable
hemoglobin mutant
Hemoglobinopathy Altering
Oxygen Affinity


Increased Oxygen Affinity

Stabilization of the Oxy conformation increases the oxygen
affinity of the hemoglobin molecule

The presence of such an effect can be confirmed by
demonstrating a left shift in the Oxygen Saturation Curve

Individuals with an increase in oxygen affinity typically
exhibit erythrocytosis
Decreased Oxygen Affinity

Stabilization of the Deoxy conformation produces a
decrease in the the oxygen affinity of the hemoglobin
molecule

The presence of such an effect can be confirmed by
demonstrating a right shift in the Oxygen Saturation Curve

Individuals with a decrease in oxygen affinity are typically
somewhat anemic
Hemoglobin M Diseases





The Hemoglobin M disorders are seen when a
substitution has occurred at the locus of either
the proximal or distal histidine
Typically, this involves a his
tyr substitution
which then forms an iron-phenolate complex
Hemoglobin with its iron in the oxidized Fe+++
state is incapable of binding oxygen
This form of hemoglobin (called Methemoglobin)
has a brownish appearance
Patients with Hemoglobin M disease are typically
cyanotic
The Sickle Cell Diseases:
Inheritance, Appearance of Symptoms,
Diagnosis





-
The most common sickle cell disease (SCD) is called sickle cell
anemia (HbSS)
However, there are a number of other SCD genotypes - compound
heterozygous states
The sickle mutation is inherited in an autosomal co-dominant
fashion
Individuals with sickle cell trait (AS) have roughly equal amounts
of HbA & HbS and are generally asymptomatic
Compound heterozygotes (e.g., SC or S-Thalassemia) generally
express a significant sickle cell disease
We dx/ with electrophoresis:
-
Hb C has a positive; HbS is neutral, HB A is negative.
Movement: HbA > HbS > HbC
Sickle Cell Anemia Pathophysiology






The presence of the abnormal (or sickle) hemoglobin
(HbS) within the cells of the affected individuals
The decreased solubility & the tendency of this
abnormal hemoglobin to polymerize when it assumes
the deoxy conformation
In HbS, the negatively charged glutamic acid at 6
position is replaced by an uncharged valine residue
In deoxy conformation, the valine at 6 position
approaches the phenylalanine at  85 position on
adjacent HbS molecule.
Multiple critical contact points that enable the
hemoglobin molecules to attach to one another
The polymer begins as a small nucleus of hemoglobin
molecules  aligned polymer with a total of 7 antiparallel pairs (or 14 individual hemoglobin chains)
SICKLE CELL DISEASE
Clinical Features









Painful Vaso-occlusive Crises
Strokes
Retinopathy
Acute Chest Syndrome
Pulmonary Hypertension
Sickle Cell Nephropathy
Biliary Tract Disease
Leg Ulcers
Avascular Necrosis of the Large Joints
SICKLE CELL DISEASE
Therapeutic Approaches


Reactivate Fetal Hemoglobin
Production using Hydroxyurea!
Chemical inhibition of Hb S
polymerization

Increase in intracellular hydration

Altering RBC/Endothelial cell interactions

Bone marrow transplantation

Gene therapy
What is this an
example of?
Typical Diseases?
Megaloblastic
Anemia



Red cells are
macrocytic.
Hypersegmented
neutrophils can be
seen.
Vitamin B12 or folate
deficiency
What Disease?
Sickle Cell Anemia
Target Cell
Sickled Cell
Platelet Function in Hemostasis – what is it called?
Primary Hemostasis!
What are the functions?
(1) Adhesion
•exposure to
collagen;
binding to von
Willebrand
factor via GPIb
receptor
(4) Aggregation and
Surface Coagulation
(2) Accumulation and
Shape Change
(3) Granule
Content
Release
•ADP released,
integrin
activation,
fibrinogen binding
Main Types of Coagulation Factors
•Zymogens/active enzymes:
Vitamin K-dependent -- factors II, VII, IX, X
Vitamin K-independent-- XI, XII, and XIII
•Cofactors:
factor V, factor VIII, tissue factor, and
von Willebrand factor
•Non-protein cofactors:
calcium and phospholipid surfaces
•Fibrinogen:
fibrinogen is converted to fibrin by thrombin
Laboratory Assays to Monitor Coagulation Parameters
•Prothrombin Time (PT)
•Activated Partial Thromboplastin Time (APTT)
•Thrombin Clot Time (TCT)
Appropriate tube to use for specimen?
Citrate solution as anticoagulant.
Stops clotting by binding calcium.
Blood to additive ratio 9:1
Plasma, NOT Serum!
Prothrombin
Time (PT)
XII
“Extrinsic”
Pathway
XI
IX
VII
VIII
X
“Common”
Pathway
V
Prothrombin (II)
Fibrinogen
PT – what does it
do?
•Test plasma + tissue
thromboplastin (source
of tissue factor) + CaCl2
 Fibrin clot
•Tests extrinsic
pathway:
–Formation of tissue
factor-factor VII
complex to
formation of fibrin.
•Prolonged PT:
–Deficiencies of
factors II
(prothrombin), VII, X,
V, and fibrinogen.
Activated Partial
XII
Thromboplastin
Time (APTT)
XI
IX
“Intrisic”
Pathway
VII
VIII
X
“Common”
Pathway
V
Prothrombin (II)
Fibrinogen
APTT – What does it
do?
•Test plasma + partial
thromboplastin (lipid) +
particulate activator +
CaCl2  Fibrin clot
•Tests intrinsic pathway:
–Activation of factor
XII to formation of
fibrin
•Prolonged APTT:
–Deficiencies of
factors XII, XI, IX,
VIII, X, V, II,
fibrinogen (and
kallikrein and
HMWK).
Thrombin Clot
Time (TCT)
XII
XI
TCT – What does
it do?
•Test plasma + thrombin
 Fibrin clot
IX
VII
VIII
X
V
Prothrombin (II)
Fibrinogen
•Measures conversion of
fibrinogen to
polymerized fibrin
•Sensitive to
quantitative and
qualitative fibrinogen
deficiencies.
Hemophilia A
Factor VIII
(VIII)
?
Hemophilia B
Factor X
?
IXa
(IX)
VIIIa
Factor Xa
Fibrinogen
Prothrombin
Va
Xa
Thrombin
Fibrin
Thrombus
Roles of Von Willebrand Factor
von Willebrand
Factor VIIIFactor (vWF)
Primary Hemostasis
Secondary Hemostasis
von Willebrand Disease (vWD)
How does it differ from classic hemophilia?
(1) Suffer from mucocutaneous hemorrhage rather
than hemarthroses like in hemophilia.
(2) Autosomal inheritance trait, so men and women have
similar prevalence, rather than X-linked like hemophilia.
(3) Consistently had prolonged bleeding times unlike the
normal bleeding times in hemophilia.
Virchow’s Triad
•Virchow (1845) thought that
thrombosis was the result of
abnormalities in:
A) the vessel wall;
B) blood flow, and
C) the properties of blood.
Thrombosis: 2 Types
•Arterial: Injury to the
endothelium; platelets adhere and
a dense platelet aggregate is
formed, and coagulation system
activated.
•”White thrombus”
•Venous: Related to decrease blood flow (stasis);
venous thrombosis is dominated by the
coagulation system, the production of fibrin-rich
thrombi.
•”Red thrombus”
Regulators of Blood Coagulation:
3 useful systems
•Protein C Anticoagulant System:
Thrombin-Thrombomodulin
Protein C and S [Activated Protein C (APC) and Protein S]
•Protease Inhibition by Antithrombin with Heparin:
Antithrombin (ATIII)
Heparin (drug)/Heparan Sulfate (naturally-occurring on
vessel wall)
•Fibrinolytic System:
Tissue plasminogen activator (tPA)
Plasminogen/Plasmin
Plasminogen activator inhibitor-1 (PAI-1)/Antiplasmin
How does the Protein C
Anticoagulant System Work?





Thrombin binds to thrombomodulin on vessel
wall
Thrombin, once bound to thrombomodulin, can
no longer cleave fibrinogen into fibrin or
activate factor V or platelets
Thrombin-thrombomodulin complex activates
Protein C (vit K dep)  APC
APC associates with Protein S
APC + S cleaves/inactivates factors Va and
VIIIa
How Does the Antithrombin
Anticoagulant System Work?




Antithrombin = serine protease inhibitor
(serpin)
Circulates freely in the plasma
Inhibits thrombin, IXa, Xa, XIa
Activity increased by:


Heparan sulfate (basement membrane)
Heparin (drug)
How does the Fibrinolysis/Clot Lysis
Anticoagulant System Work?

Plasminogen freely circulates in the plasma
Endothelium secretes tissue-type plasminogen
activator (tPA)
tPA converst plasminogen  plasmin
Plasmin lyses clots
Plasminogen activator inhibitor-1 (PAI-1) is
secreted by endothelium
PAI-1 downregulates tPA activity

It’s another fine balancing act!





Thrombosis
Why heparin therapy?
Inhibits further thrombus formation almost immediately.
Why warfarin therapy?
Depletes vitamin K-dependent factors to impair procoagulant
function.
Why tissue plasminogen activator therapy?
Degrades thrombus to re-establish blood flow.
Family history?
Necessary to determine if familial or acquired clinical scenario.
Common hereditary cause of venous thrombosis?
factor V Leiden: a plasma protein “resistant’ to inactivation by
the protein C system
Some Acquired Causes of Venous Thrombosis
Surgery and trauma
Prolonged immobilization
Older age
Cancer
Myeloproliferative disorders
Previous thrombosis
Pregnancy
Use of contraceptives or hormone-replacement therapy
Anti-phospholipid antibodies
Anticoagulant Therapy: Medications
•Heparin-
Heparin binds to antithrombin, which
converts it to a very potent and immediate inhibitor of
thrombin, factor Xa and other proteases in the clotting
cascade. IV
•Warfarin (or Coumadin)-
Oral anticoagulants
produce their effect by interfering with the cyclic interconversion of vitamin K and its 2,3 epoxide (vitamin K
epoxide).
•Fibrinolytic enzymes-
Induction of a fibrinolytic
state by the infusion of plasminogen activators is used in
massive pulmonary embolism and to restore the patency of
acutely occluded arteries.
Benefits of Low Molecular Weight Heparins (LMWH)
•LMWHs have a higher affinity for antithrombinfactor Xa.
•Longer plasma half-life.
•Safe and effective for venous thromboembolism, and
with unstable angina or acute thrombotic stroke.
•Convenient, given subcutaneously without laboratory
assay monitoring (allowing for patient and home care
options).
GENERAL Heparin Targets
-Thrombin
-IXa, Xa, XIa, XIIa
-Measure efficacy with APTT
Vitamin K Cycle and Effect of Warfarin
•Vitamin K antagonists exert their anticoagulant effect by
inhibiting vitamin K epoxide reductase and vitamin K reductase
activities.
•All vitamin K-dependent coagulant proteins are impaired:
prothrombin,
factor VII,
factor IX,
factor X,
anticoagulant protein C and protein S
•Oral anticoagulants cause hepatic production and secretion of
partially and fully de--carboxylated and dysfunctional proteins.
•Can reverse effects with emergency administration of Vitamin K
•Monitored by PT; most closely reflects VII (shortest K-dep ½
life)
•Must avoid use during pregnancy!
•PO administration
Treatment of Venous Thromboembolism
•Treatment strategy differ between arterial from
venous circulation.
•Objective of treating/preventing venous thrombosis:
-prevent extension of thrombus;
-prevent thrombus from embolizing;
-render fibrin more susceptible to fibrinolysis.
(standard in threat of massive PE)
-standard tx in acute venous thrombosis & PE
heparin + oral vitamin K antagonists
Arterial Thrombosis



Main pathogenic mechanism for acute MI,
unstable angina, sudden coronary death
Tx: heparin, LMWH, warfarin, anti-platelet
cmpds, fibrinolytics, ASPIRIN
Clopidogrel and Ticlopidine inhibit platelet
aggregation by blocking ADP receptor on
platelet and inhibiting activation of GPIIb/IIIa.


But Ticlopidine may cause TTP!
Abciximab (ReoPro), Eptifibatide (Integrilin),
Tirofiban (Aggrastat) bind GPIIa/IIIa receptor
on platelets preventing fibrinogen binding
What is this? What will it give rise to?
A Megakaryocte that will shed off Platelets!
Platelet Plug Formation

Adhesion



Aggregation

Platelets stick to each other via fibrinogen bridges.
GPIIb/IIIa to fibrinogen
Activators: ADP, collagen, 5HT, Epi, TXA2, thrombin
Providing a phospholipid
scaffold for coagulation
Secretion
Platelets release granular contents and potentiate
reactions,
like generation
clotting
Spits out pro-clotting materials: ADP, Epi, factor V,
offibrinogen
Xa and thrombin!
vWF,



And another
role
of wall.
platelets?
Platelets
stick to injured
vessel
GPIb/IX to vWF and collagen


Thrombocytopenia
three broad categories of causes
Underproduction
 Peripheral Destruction
 Splenic sequestration

If you saw this in a blood sample and were
told the patient has too few platelets, what
would you say?
WRONG!!!
It’s Pseudothrombocytopenia!
Or in Dr. Ma’s words, you
could say “damn, there’s more
than one platelet on this field”
YIKES! What’s this?
Petechiae
What’s the difference?
ACK, and this?
Purpura are formed
when Purpura
petichiae coalesce
Thrombocytopenia –
Underproduction Causes




Marrow failure: myelodysplasia, aplastic
anemia, vitamin deficiencies (B12/folate)
Marrow infiltration: tumor, granulomatous
diseases, fibrosis, leukemias, lymphomas
Marrow toxins: drugs (esp. alcohol),
radiation, infections
Congenital: Wiskott-Aldrich Syndrome,
Thrombocytopenia Absent Radius
Syndrome (TAR), May-Hegglin
DIC- Diagnosis

Elevated PT - due to consumption of Factor VII,
which has the shortest half-life (4 hrs) of all
clotting factors.




Low platelets
Low/falling fibrinogen
Elevated fibrin degradation products



When advanced, the APTT can be prolonged as well,
as the other clotting factor levels fall.
(FDPs/FSPs) or D-Dimers
Can see a few schistocytes on the peripheral
smear in most cases. (MAHA)
Low clotting factor levels
DIC - Etiologies and Treatment

Can be associated with:






gram negative sepsis,
severe burns,
obstetrical disasters,
certain leukemias or tumors,
shock,
insect or snake venoms

TREAT THE UNDERLYING CAUSE!!!

Supportive measures can include:



transfusion of platelets
clotting factors, fibrinogen
+/- low dose heparin to halt thrombin generation.

Low dose heparin can slow down the forest fire…
TTP - Diagnostic Features
(aka “The Pentad”)





What’s normal in TTP that’s
NOT in DIC?
Microangiopathic Hemolytic Anemia (MAHA) – MUST BE
PRESENT
 Elevated LDH, elevated bilirubin
 Schistocytes on the peripheral smear
 MUST BE PRESENT
Low platelets - MUST BE PRESENT
Fever
Neurologic Manifestations
- headache, sleepiness, confusion, stupor, stroke, coma,
seizures
Renal Manifestations
 hematuria, proteinuria, BUN/Creatinine
PT, fibrinogen levels,
FDPs/D-dimers
TTP - etiology



Associated with an antibody against or a deficiency of
the protease (ADAMTS-13) that cleaves the very high
molecular weight multimers of von Willebrand’s factor
vWF accumulates  abnormal platelet adhesion and
activation
Can be induced by drugs, including






ticlopidine,
quinine,
cyclosporine,
FK-506,
mitomycin C
Increased incidence with pregnancy or HIV
TTP - Treatment

Treatment relies on PLASMA EXCHANGE.





Remove all inciting agents (ultra-high MW
multimers of vWF)
Restoring ADAMTS-13
Adjunct therapies, including glucocorticoids and
anti-platelet agents can be used but are of
uncertain benefit.
Secondary measures if no response to
plasma exchange include splenectomy,
vincristine.
AVOID PLATELET TRANSFUSIONS THEY “FUEL THE FIRE”
Thrombocytopenia Drugs/Immune Mechanism

Drugs can lead to immune-mediated
thrombocytopenia by a variety of mechanisms.
1) directly stimulating anti-platelet
antibody production
2) a hapten mechanism
3) “innocent bystander” phenomenon.
Thrombocytopenia Drugs/Immune Mechanism
“Qua – BASH” (don’t ask me, I’m sleepy)
 Quinine/quinidine
 Beta-lactam antibiotics
 Abciximab (ReoPro®)
 Sulfa drugs like Trimethoprimsulfamethoxazole
 Heparin
ITP - Therapy





Initial therapy relies on use of
corticosteroids (e.g. prednisone). These
can take 48-72 hrs to take effect.
If platelet count is <10K or if patient is
bleeding, need more rapid therapy--use
IVIg
If patient is Rh positive, can use Anti-D
(WinRho®) in place of IVIg. (need a
spleen)
2nd line – splenectomy
3rd line - immunosuppression
Compare TTP, DIC, ITP
TTP
DIC
ITP
Low platelets
Must have
Usually
Must have
Schistocytes
Must have
Maybe
Never
PT/FDP/
Fibrinogen
Normal
Low
n/A
Transfuse
platelets?
NEVER
Maybe
Only if pt is
bleeding
Treatment
Plasma
exchange
Tx under- Steroids,
lying cause IVIG, AntiD
Qualitative Platelet Disorders - Differential
Congenital -



Glanzmann’s thrombaesthenia - defect in IIb/IIIa
Bernard-Soulier - defect in Ib/IX
Acquired





uremia
Drugs - ASA, NSAIDs, antibiotics, ReoPro®,
Herbs - ginkgo, garlic, Vitamin E
Myeloproliferative diseases
Diagnosis?
Normal APTT/PT/TCT, prolonged bleed time
Anti-Platelet Drugs

Aspirin



Thienopyridine Derivatives




Inactivates COX-1, decreasing TXA2 (a platelet
agonist)
Prevent stroke, MI, CAD, peripheral arterial occlusion
Ticlopidine, Clopidogrel
Blocks ADP (platelet agonist)
Ticlopidine may cause TTP
GPIIb/IIIa inhibitors


Abcizimab (ReoPro), Eptifibitide (Intergrillin),
Tirofiban (Aggrastat)
Blocks platelet aggregation by blocking fibrinogen
receptor on platelets
Donor screening criteria:
Allogeneic (volunteer)




Hgb >12.5
BP, pulse: healthy
Uniform Donor screening questionnaire
Infectious Disease Screening of donor






Hepatitis B
Hepatitis C
HIV I/II
HTLV I/II
Syphilis
Autologous (for self): Less stringent criteria
Parts Collected Out of a
Whole Blood Collection
 pRBC
 Platelet
rich plasma (platelet
concentrate)
 Plasma (FFP)
pRBC Storage




RBCs suspended in
 anticoagulant (citrate based) and,
 Additive Solution - AS
 Provides nutrients to support RBC metabolism
42 days = Shelf life
Volume= 250 to 300 mL
 65% RBCs, 35% plasma and AS
 contains WBC’s and some platelets
may be frozen w/ glycerol (cryoprotectant) for 10 yrs
pRBC Transfusion





1 unit = 1 g/dL Hb; 3% hematocrit
Decide w/ clinical judgement NOT lab values
Transfuse slowly, so you can catch adverse rxn
RBCs should be infused alone or with 0.9% NaCl
through a 170µm clot-screen filter
NEVER mixed with :

Calcium containing solutions


Dextrose




May cause clumping or clots
Hypotonic,may cause hemolysis or clumping
Medications
Hypertonic solutions
AVOID infusing with Lactated Ringers
Fresh Frozen Plasma:
Storage, Contents, Tx?
Frozen w/in 8hrs of collection
 Stored -20º C for up to 1 year
 Once thawed, can be kept at 1-6º C for 24 hrs
Contents:
 1 unit/mL of all clotting factors including labile Factors V and VIII
 ~400 mg fibrinogen
 Citrate as anticoagulant
 No platelets
Treatment of multiple coagulation factor deficiencies
 Massive transfusion
 Trauma
 Liver disease
 DIC
 Unidentified deficiency



Platelets: Storage, Dosing, Treatment, Matching





Pooled platelet concentrates (PC’s) from several whole
blood donations or apheresis
Suspended in citrated plasma
Stored @ 20-24º C for 5 days only  highly
susceptible to shortages!!!
One therapeutic dose  platelet count 30-50k
PLT surface




Trace amts RBC’s  Rh type important



ABO antigens but not Rh
Platelet specific Ags
HLA- A and HLA-B
Rh- female gets Rh- PLT
Tx: thrombocytopenia, qualitative defects
Monitor efficacy of transfusion via PLT count w/in 1hr
of transfusion  conserve resources…
Cryoprecipitate: Contents, How
to Get it, Tx, Dosing?
Cold insoluble white precipitate
 Forms when FFP is thawed at 1-6º C
 Removed from FFP by centrifugation, then refrozen at –20º C
CONTAINS:
 80 to 150 IU Factor VIII:C (antihemophilic factor)
 150 mg fibrinogen
 Von Willebrand Factor
 Tx:
 Deficiency of fibrinogen, Factor VIII
 Improve platelet function in uremia
 Dose calculation based on
 Patient’s weight and hematocrit : plasma volume
 Desired increase in Factor level

ABO Blood Group: Population Frequency
O
A
B
AB
45%
41%
10%
4%
What is ABO?


specific terminal sugar residues on a large
glycolipid backbone on the RBC membrane
The ABO genes




Codominant inheritence
Encode for a glycosyl transferase enzyme
Adds the specific terminal sugar to the glycolipid
backbone
Convey immunogenicity
O = fucose
 A = N-acetyl galactosamine
 B = galactose

ABO Discrepancy

when the front and back types do not
match




Front = antigen on cells
Back = antibody in serum
Must resolve prior to transfusion
Common Causes:




Cold agglutinin
Weak or absent antibodies in elderly or infants
Interfering substance: protein, dextran
Weak subgroup of A or B
RECIPENT
BLOOD TYPE
RED CELLS
PLASMA
B
Whose
Whose
O
O, A, B, AB
RBCs
Plasma
A,
O
A,
AB
Can they Can they
B, O
B, AB
Take?
Take?
AB
AB, A, B, O
O
A
AB
ABO Antibodies
ABO Antibodies
anti A , anti B
Predominantly IgM >> IgG > IgA



IgM reacts at room temperature
Can bind complement  intravascular
hemolysis
Naturally occurring

Anti A and B form due to similar antigens in nature




(bacteria, pollen, etc)
Transfusion exposure or pregnancy NOT required
IgM pentamer can agglutinate RBCs
Immediate transfusion reactions possible
Rh Blood Group: the 2nd most impt
Rh System : family of 51 antigens
 Integral membrane proteins, well formed during fetal development
 Rh Antigens of routine importance: D, C, c, E, e
 Rh null are individuals lack all Rh proteins
 Clinically significant in:



Transfusion practice
Transfusion reactions
Hemolytic disease of newborn
D Antigen (Rh Type)




D+ 85% prevalence
D- 15%
Highly immunogenic
= Rh+
= Rh-
Clinically significant with RBC transfusion & platelet transfusion

Females of child bearing potential need Rh- blood
Immune sensitization required to develop Rh system antibodies




Transfusion or pregnancy
IgG , react at 37° C - must incubate in the lab to demonstrate them
Typically cause extravascular hemolysis, if present
Some may activate complement and cause intravascular hemolysis
Comparison b/tw ABO and Rh
Blood Groups
ABO




IgM >> IgG > IgA
Test at room temp
Causes intravascular
hemolysis
Naturally occurring

Bacteria, pollen
Rh




IgG
Test at body temp
Causes extravascular
hemolysis
Sensitization required

Pregnancy, transfusion
RBC Blood Groups and
Antibodies

Other protein blood groups






Integral membrane proteins are well formed
at birth
Antibodies predominantly IgG
Delayed Transfusion Reactions



Kell
K
Duffy Fy a , Fy b
Kidd Jk a, Jk b
Extravascular hemolytic reactions
Intravascular hemolysis more likely with Kidd Jka,
Jkb due to complement binding
Hemolytic disease of newborn
Front & Back Types
FRONT TYPE –what’s on the cells?


BACK TYPE – what’s in the serum?


Mix 2 drops of patient cells with 2 drops of
reagent antibodies to A, B and D antigens in
different test tubes, Agglutination indicates
presence of antigen
Mix 2 drops patient serum with both A and B
reagent cells. Agglutination indicates presence of
antibody
Front and back types should match
Antibody Screen


Determines if patient has antibodies to the other
major blood groups
Requires



Combining pt serum with 3 different RBCs with known
blood group phenotype
Incubate at 37 C to detect IgG antibodies
Addition of Coombs serum


Anti-human IgG : enables in vitro agglutination if IgG present
due to monomeric structure of IgG
If screen is +, antibody specificity is determined
by a more extensive panel of testing RBCs
Types of Crossmatch

Immediate Spin Crossmatch


Full Crossmatch



Rapid, room temp mixing of patient serum with donor
RBCs to confirm ABO compatibility
For patients with antibodies
Requires incubation and Coombs serum to confirm
the patient’s IgG will not react with donor RBCs
Electronic Crossmatch

Alternative for Immediate spin crossmatch for
patients without antibodies
Special Circumstances

Emergency Release




When delaying transfusion poses risk of
death
Insufficient time to perform type screen and
crossmatch
Requires MD signature
Conditional Release


Blood may be crossmatch compatible
however, blood bank testing is incomplete or
cannot completely resolve antibody testing
(ex: warm auto antibody)
Requires MD signature
Component Modifications
Leukocyte reduction
 Filtration with specialized leukocyte removing filters  3 log leukocyte
reduction



Prevent CMV transmission
Prevent alloimmunization to leukocyte antigens for those w/ chronic transfusion
Prevent recurrent febrile non-hemolytic transfusion reactions
Washing
 Removal of plasma by washing RBC or platelets with saline



For prevention of severe allergic reactions
Anaphylaxis
IgA deficiency
Time consuming , labor intensive, delays transfusion, decreases transfusion
increment slightly
 Does not substitute for leukocyte reduction
Irradiating
 Prevent graft versus host disease GVHD (Transfusion is a transplant)
 Indicated in severe immunodeficiency settings






BMT
Hematopoietic malignancies undergoing chemotherapy
Premature infants
Severe combined immunodeficiency
Blood products from relatives must also be irradiated due to HLA antigens
Adverse Effects of Transfusion
Acute Immune Transfusion Reactions < 24 hours





Allergic
Hemolytic
Febrile, non-hemolytic
Anaphylactic
Transfusion related acute lung injury (TRALI)
Delayed Immune Transfusion Reactions > 24 hours




Hemolytic
GVHD
Platelet refractoriness
Post transfusion Purpura (development of anti-platelet antibodies)
Acute Non-Immune Transfusion Reactions


Circulatory Overload (Volume excess)
Septic shock from bacterial contamination of blood product
Delayed Non-Immune Transfusion Reactions


Iron Overload
Infectious Disease transmission
Suspected Transfusion Reaction

Hemolytic reaction symptoms are not
specific and include:









Fever
Chills
Hypotension
Oozing from IV site
Back pain
Hemoglobinuia – red urine
If any of these occur STOP transfusion, provide
appropriate supportive care, notify blood bank
Send repeat samples for blood bank evaluation
DO NOT restart the unit

Exceptions: mild urticaria that responds to antihistamine
White Cells
What are the cell types?

Granulocytes






Neutrophils
Band forms
Eosinophils
Basophils
Lymphocytes
Monocyte/Macrophages
ID the cell!
Band Cell
Eosinophil
Basophil
Monocyte
Lymphocyte
Neutrophil
What is this? What does it do?

Neutrophils!



PMNs (polymorphonuclear neutrophils)
polys
segs (short for segmented neutrophils)

Most common white cell
Pale pink granular cytoplasm with
condensed, segmented nucleus
7 hr ½ life

Functions include





chemotaxis,
phagocytosis,
killing of phagocytosed bacteria
What is this? What does it do?
Eosinophil
 Granulocytes with large, refractile,
orange-pink granules.
 Nucleus is typically bilobed.
 Functions include all PMN functions,





Chemotaxis
Phagocytosis
Killing of phagocytosed bacteria
serving as effector cells for antibodydependent damage to parasites,
regulation of immediate-type
hypersensitivity reactions

inactivation of histamine and leukotrienes
released by basophils and mast cells
What is this? What does it do?
Basophils
 Large, dark blue granules which
overlie the nucleus.
 The most uncommon of all
granulocytes
 Functions include



mediation of immediate-type
hypersensitivity
modulation of inflammatory responses
by releasing heparin and proteases
Precursor of tissue mast cells
What is this? What does it do?
Lymphocyte
 Lymphocytes have an oval nucleus,
with a thin rim of blue cytoplasm.
 There may be a few very fine
purplish-red granules.
 The nuclear border is smooth.
 Functions in immune regulation and
production of hematopoietic growth
factors.
 Functions in


immune regulation and
production of hematopoietic growth
factors.
What is this? What does it do?
Monocyte
 Largest white cell normally found in the
periphery
 Has a folded nucleus with uneven countour
 Slate grey cytoplasm--there may be
vacuoles
 Functions Include:






chemotaxis,
phagocytosis,
killing of some microbes,
antigen presentation,
release of IL-1 and TNF, which stimulates
bone marrow stromal cells to produce
growth factors, including: GM-CSF, G-CSF,
M-CSF, and IL-6.
Precursors of tissue macrophages
Causes of Elevated Neutrophil Count

Physiologic –











exercise,
pregnancy,
lactation,
neonates
Acute infections
Acute inflammation – surgery, burns, infarcts, crush
injuries, acute gout, rheumatoid arthritis
Acute hemorrhage
Non hematologic malignancies
Myeloproliferative disorders, esp CML
Drugs: corticosteroids, G-CSF, lithium
Misc: seizures, electric shock, post-splenectomy,
Leukocyte Adhesion Deficiency
Causes of Neutropenia


Physiologic - in African-Americans
Drugs –









anti-psychotics,
anti-epileptics,
anti-thyroid, and
some antibiotics (gold, sulfa)
Chemotherapy
Infections: viral, overwhelming bacterial sepsis, TB,
fungal
Immune - lupus, rheumatoid arthritis (Felty
syndrome)
Familial
Hypothyroidism, hypopituitarism
What is Agranulocytosis? Major Sxs?


This is the complete or near-complete absence of
neutrophils in the peripheral blood, with a normal
platelet count and hgb
Almost always drug-induced





Clozaril (and other newer antipsychotics)
Propythiouracil (antithyroid)
Anti-convulsants
Sulfa and chloramphenicol antibiotics
Causes severe necrotizing ulcers in the mouth
and throat
What is basophilia a major symptom of?
chronic myeloproliferative diseases
Causes of Eosinophilia

Differential Diagnosis for elevated
eosinophil count “NAACP”:





Neoplasm,
Allergy/asthma,
Addison’s disease,
Collagen vascular disease
Parasites
Causes of Lymphocytosis




Viral infections
Bacterial infections - whooping cough
(pertussis), TB, syphilis, brucellosis
Chronic Lymphocytic Leukemia (CLL)
Lymphomas and Waldenstrom’s
macroglobulinemia
Causes of Lymphocytopenia





Immunodeficiencies, including HIV/AIDS
Immunosuppresive drugs, including
corticosteroids
Lymphomas
Granulomatous diseases, including sarcoid, TB
Alcoholism, malnutrition, zinc deficiency
Causes of Monocytosis






Bacterial infex: TB, syphilis, subacute bacterial
endocarditis, typhoid, brucellosis
Protozoal infex: malaria
Rickettsial infex: RMSF, typhus
Myelodysplastic syndromes (just one of them)
Leukemias
Inflammatory bowel disease
Normal Neutrophil Function

Adherence



Chemotaxis


Moving along a concentration gradient to higher [ ]s
Recognition/Phagocytosis



Rolling mediated by selectins
Adhesion mediated by beta-2 integrins
Via complement and IgG
Once it eats, it’s got a phagosome
Degranulation

Granules are released INTO the phagosome




NADPH oxidase: O2  O2Superoxide dismutase: O2-  H2O2
MPO: H2O2  HOCl
Oxidative Metabolism and Bacterial Killing
Defects in Neutrophil Function
Acquired Defects




Corticosteroid Use Alcoholism
Leukemias
Myelodysplasia
Myeloproliferative disorders
Congenital Defects




Leukocyte Adhesion Deficiency
Chronic Granulomatous Disease
Myeloperoxidase Deficiency
Chediak Higashi Syndrome
Erythrocytosis – What is it?


An increase in the number of circulating RBCs per
volume of blood.
Reflected as an elevated hemoglobin and hematocrit.



Relative Erythrocytosis (Gaisbock’s syndrome)



Depressed plasma volume, RBC mass is normal
Common in middle age men w/ HTN, smoking hx
Secondary Erythrocytosis



>60% in man, >57% in woman = true erythrocytosis
Red cell mass study if elevated but not quite these levels
Erythropoietin production increased by kidney/liver
Tissue hypoxia, tumors, genetic disorders, drugs for athletics
will all increase Epo
Primary Erythrocytosis

The bone marrow is going crazy without outside input
Why is erythrocytosis bad?
Hyperviscosity Syndrome


Your blood gets too sludgy
Symptoms include:






Headaches
Visual changes
Tinnitus
Dizziness
Paresthesias
Decreased mental acuity
Erythrocytosis due to appropriate
increases in epo






Life at high altitude
High affinity hemoglobins
Cardiopulmonary disease
Obesity-Hypoventilation syndrome
Obstructive sleep apnea
High carboxyhemoglobin levels
What are the Myeloproliferative
Diseases? Definition? Associated sxs?

Includes:







Myeloproliferative disorders are Stem Cell Disorders
leading to autonomous production of hematopoietic
cells from ALL THREE LINEAGES (red cells, white cells,
platelets).
All of these disorders are clonal (except for a subset of
ET cases)
Associated sxs:



Polycythemia vera
Essential Thrombocythemia
Myelofibrosis
Chronic Myelogenous Leukemia
Basophilia
Splenomegaly
Potential to develop into AML
Polycythemia vera
Most of cells in circulation are derived from a single,
neoplastic stem cell
 Does not need Epo to produce more cells…
 Diagnosis based on low/absent levels of Epo
Natural History – 4 phases:
 Latent phase - asymptomatic
 Proliferative phase -pts may have sxs of:






Hypermetabolism
Hyperviscosity
Thrombosis
Spent phase -  red cell mass, anemia, leukopenia,
secondary myelofibrosis, increasing HSM. 20% of pts
Secondary AML aka when the body says “screw it, I’m not differentiating anymore”

1-2% of pts treated with phlebotomy alone
Symptoms of Polycythemia Vera

Those common to ALL erythrocytosis









Pruritis after bathing
Hypermetabolic sxs
Erythromelalgia
Thrombosis
Hemorrhage
PE findings





Headache
Decreased mental acuity
Weakness
Facial plethora
Splenomegaly
Hepatomegaly
Retinal vein distension
Lab findings



BASOPHILIA
Low EPO levels
Increased Hbg/HCT, WBCs, platelets, uric acid, B12, leukocyte alkaline
phosphatase score
P vera - Treatment



Phlebotomy – Draw 500 cc blood 1-2x/wk to target Hct 45%; maintain BP w/ saline
 Generally, the best initial treatment for P vera – rapid onset
 Downsides:
 Increased risk of thrombosis
 No effect on progression to spent phase
 May be insufficient to control disease
Myelosuppressive agents
 Hydroxyurea
 can be used in conjunction with phlebotomy
 May increase the risk of leukemic transformation from 1-2% to 4-5%
 32P – kills some of the proliferating cells!
 increase the risk of leukemic transformation from 1-2% to 11%
 Single injection may control hemoglobin and platelet count for a year or more.
 Alkylating agents such as busulfan
Interferon alpha
 Benefits
 No myelosuppression
 No increase in progression to AML
 No increase in thrombosis risk
 Drawbacks
 Must be given by injection up to daily
 Side effects may be intolerable in many pts: flu-like symptoms, fatigue, fever,
myalgias, malaise
So what disease are you thinking?
Arrow indicates a giant platelet, larger than
the red cells or lymphocyte
Essential Thrombocythemia
Essential Thrombocythemia



Increased megakaryocyte production of platelets
Must exclude secondary causes of thrombocytosis and
other myeloproliferative disorders
Major complications:







Thrombosis: 20-30% of all patients; Budd-Chiari
Microvascular thrombi/digital ischemia
Pruritis & erythromelalgia
Acquired von Willebrand’s disease
Will see clusters of abnormal megakaryocytes on
smear
Platelet morphology will be big and odd-shaped
Treatment:



Anagrelide – platelet lineage specific
Hydroxyurea
Interferon alpha
Myelofibrosis







Clonal stem cell disorder affecting megakaryocytes
predominantly
All myeloproliferative disorders can result in a spent
phase which can be difficult to distinguish from
primary MF
Myeloid metaplasia refers to earlier proliferative phase
where extramedullary hematopoiesis predominates.
WILL become AML  median survival is 5yrs
Splenomegaly and hepatomegaly
Aspirate is a “dry tap”
Peripheral blood smear: leukoerythroblastic



Teardrop RBCs
Nucleated RBCs
Early granulocytes/precursors
Myelodysplastic Syndromes




Definition: disordered maturation in 1 or more cell lines
producing cytopenias: anemia, leucopenia, thrombocytopenia
or combos
More common in the elderly
Based on cytogenic abnormalities
Peripheral cell abnormalities








Macrocytic RBCs
Large platelets
Hypogranular or bilobed nuclei neutrophils
Megaloblastic erythropoeisis
Ringed sideroblasts
Abnormal nucleus of RBC precursors (dyserythropoiesis)
Small megakaryocytes with abnormally hypolobate nuclei
Blast cells should account for <30% of marrow cells