Hematologic Flashcards
Most important diagnostic test when evaluating anemia?
CBC
Life span of erythrocyte (RBC): ___ days
100-120 days
Primary responsibility of erythrocyte (RBC) is ____? Do mature erythrocytes have a nucleus?
oxygenation
no
What’s the main type of WBC (60-70%)?
Neutrophils
Chief phagocytes in early inflammation;
Bands (immature ones) and Segs
mature ones
Do platelets have nucleus or DNA? What’s the life span and what are they removed by? What are they formed from? They are essential for blood ____.
NO nucleus or DNA
life span: 10 days, removed by spleen
formed from megakaryocytes
Essential for blood coagulation and control of
bleeding
Hematopoiesis occurs in ___ and ___ of fetus; only in ____ after birth
liver and spleen of fetus
bone marrow after birth
Stimulation of undifferentiated cells –> differentiated cells
Can increase to replenish destroyed cells or
during infection
Hematopoiesis
9 components of CBC
WBC RBC Hgb Hct MCV RDW MCH MCHC Platelets
Stimulates hematopoietic stem cells to
differentiate into proerythroblasts
Can also induce cells to pass through
differentiation and maturation more quickly
Erythropoietin
Retic count marker of ____ function
bone marrow
What is the WBC in the CBC, and what does it tell us?
Measure of # of leukocytes in volume
Tells us: Infection, bone marrow suppression
What is the Hgb in the CBC, and what does it tell us?
Measure of the component of
RBC that binds O2, g/dL
Tells us: Oxygen carrying capacity
What is the Hct in the CBC?
Fractional volume of whole blood occupied by RBCs; %
What is the MCV in the CBC, and what does it tell us?
Indicated the average size of the RBC
Tells us: Classify anemia as microcytic, normocytic or macrocytic
What is the RDW in the CBC, and what does it tell us?
Measure of variability in RBC size in sample
Tells us: Elevated means greater cell size
variability; increases w/nutritional anemias
What is the MCH in the CBC, and what does it tell us?
Measures average weight of hemoglobin per RBC
Usually follows the pattern of the
MCV
What is the MCHC in the CBC, and what does it tell us?
Concentration of hgb in RBC; Calculated value of Hgb/Hct
Classify anemia as hypochromic, normochromic, hyperchromic
What are the neutrophils in the Diff and what can it tell us?
1st line of defense in infection
Bacterial infection,
neutropenia; bands, stabs
What are the Lymphocytes in the Diff and what can it tell us?
B and T cells produced in lymphatic system
Acute viral or chronic
bacterial infection
What are the Monocytes in the Diff and what can it tell us?
2nd line of defense in infection
Viral infection
What are the Eosinophils in the Diff and what can it tell us?
Commonly produced in
response to allergic infxn
Allergic disorders, parasitic infections
What are the Basophils in the Diff and what can it tell us?
Responsible for histamine
release
Systemic allergic reaction
The reticulocyte count is a measure of the ___ response to anemia
bone marrow
After newborn period, normal retic count is ___-___%
0.5-1.5%
Definition of anemia
Hemoglobin and/or
hematocrit at or below
2.5th percentile for
age, race, sex
Normal nadir for physiologic anemia from birth-3 months occurs at ____ weeks
6-9
From 3-6 months, anemia is likely ____
hemoglobinopathy
From 6 months-teens, ___ causes are the more likely cause of anemia
acquired (iron-deficiency anemia)
Screen all children at ___ months for IDA
12 months
Pathologic anemia during birth-3 month period definition (4 components):
- HgB <13.5 in 1st month
- Hgb <9 otherwise
- signs of hemolysis
- sx of anemia
3 main examples of Microcytic anemia
Iron Deficiency Anemia
Thalassemia
Anemia of chronic
disease
3 main examples of normal anemia
Sickle cell disease
G6PD
Hemolytic anemia
2 main examples of microcytic anemia
Vitamin B12 or
folate deficiency
Congenital aplasia
Definition of iron-deficiency anemia
Insufficient iron to maintain normal function
such that iron stores are reduced
Hgb >2 SDs below normal as a consequence
of iron deficiency
risk factors for iron-deficiency anemia
- Low SES
- Prematurity, low birth weight
- Lead exposure
- Exclusive BF >4 mo w/o iron supplementation
- Weaning to whole milk early
- Feeding problems
- Poor growth
- Inadequate nutrition
tx for iron deficiency anemia
Iron therapy 6 mg/kg/day divided TID
Anemia of Chronic Disease often have Hb in range of ___-____
8-12
Anemia of Chronic Disease Likely due to:
inflammatory cytokines that inhibit erythryopoeitin
3 components of Diagnosis for Anemia of Chronic Disease
low Hb, microcytosis, low retic count
Tx for Anemia of Chronic Disease
correct underlying disease
- Group of inherited disorders of Hgb synthesis
* Autosomal recessive
Thalassemias
Think of these if microcytic anemia not responsive to
iron therapy?
Thalassemias
Thalassemias not typically symptomatic until __ months of age
6
Thalassemias Pathophysiology
– Alpha thalassemia: ___ genes control alpha globin
synthesis
– Beta thalassemia: ___ gene controls beta globin
synthesis
alpha: 4
beta: 1
α-Thalassemia predominantly affects what ethnicities?
black, Mediterranean, Middle Eastern,
Chinese, or SE Asian descent
What is the most fatal α-Thalassemia?
α-thalassemia major
Which is more common, α-Thalassemia or β-Thalassemia?
β-Thalassemia
β-Thalassemia predominantly affects what ethnicities?
black, Mediterranean, Middle Eastern, or Asian
descent
Most severe type of β-Thalassemia? Is it symptomatic at birth?
β-thalassemia major/Cooley’s anemia
NO asymptomatic
at birth
α or β trait Thalassemias Clinical Manifestations (2)
mild microcytic anemia,
asymptomatic
Hb H: Thalassemias Clinical Manifestations (4)
mild hemolytic anemia, jaundice, HSM,
gallstones
β-thalassemia intermedia: Clinical Manifestations (2)
moderate hemolytic anemia (Hb >7 g/dL), splenomegaly
β-thalassemia major Clinical Manifestations (3)
Massive HSM, growth failure, bony deformities
Screening for Thalassemias?
newborn screening
α or β trait Thalassemias tx?
none
HbH Thalassemia tx?
folic acid supplemenation
Beta-thalassemia major tx>
Transfusion therapy (Goal: Hb 9-10 g/dL pre-transfusion)
Iron chelation therapy
What is considered the curative tx for Thalassemia?
stem cell transplant
Example plan for alpha-thalassemia minor/trait (3 components)
Refer to hematology, monitor, family
counseling and testing
G6PD Pathophysiology: enzyme instability…older red cell instability means less protection against ____
oxidant stress
G6PD is __linked recessive. Most common red cell enzyme defect (African, Mediterranean, Asian)
X
Clinical Manifestations of G6PD - neonatal? in older children? with oxidant stress?
Neonatal jaundice
- Older children- asymptomatic until oxidant stress
- With oxidant stress- dark urine, Pallor, jaundice, N/V, tachycardia
G6PD: Medication Avoidance. Important to avoid oxidative stressors, which includes ____, ____, and ____ (meds/foods)
Note that ___ and ___ can also be oxidative stressors
sulfonamides, antimalarials, fava beans
fever and tachycardia
Tx for G6PD
– Avoid triggers
– No fava beans
Diagnosis for G6PD
– CBC, retic count and smear abnormal only with
oxidant stress
– Confirmation: decreased levels of G6PD in erythrocytes
• Characterized by Hb S
• Substitution of valine for glutamic acid on surface of hemoglobin S molecule
– Deoxygenation and dehydration –> solidifying and stretching into long, rope-like fiber
– Causes classic crescent shape and decreased RBC
deformability
– Log jam effect
Sickle Cell disease
Is sickle cell part of universal newborn screening?
yes
Clinical manifestations of sickle cell typically appear by ___ mo. when fetal hemoglobin disappears
6-12
2 main clinical manifestations of sickle cell
Vasoocclusion and hemolysis
– Vasoocclusion: recurrent painful episodes + organ
complications
– Hemolysis: chronic anemia + gallstones
Common acute complications of sickle cell
Vaso-occlusive events Splenic sequestration Acute chest syndrome Stroke Dactylitis Aplastic crisis Priapism
Prevention of Complications from SCD involves what 4 components?
– Penicillin prophylaxis
– Appropriate, timely immunizations
– Blood transfusions for those at risk of stroke
– Medication therapy: Hydroxyurea
Why are SCD patients more at risk for infection? (5)
***functional asplenia, reduced
tissue perfusion, presence of indwelling
catheter, splinting, hypoventilation
Infection prevention in SCD patients involves prophylactic ___ <5 y.o. What’s the dosage?
penicillin
– Age 3 mo-3 yrs: 125 mg penicillin V PO BID
– Age 3-5: 250 mg penicillin V PO BID
Immunizations in Sickle Cell Disease include all routine immunizations PLUS (3)
- Pneumococcus- PCV13 + PPSV23
- Meningococcus
- Influenza
– 90% of SCD patients have experienced _____ by age 6
Vasoocclusive Pain
Tx for Vasoocclusive Pain? What is it caused by? Is it a diagnosis of exclusion?
Treatment: Rapid initiation of analgesics • Opioids (Morphine or Dilaudid) • Hydration • Physical Therapy • Psychologic
Caused by log jam effect
Y Diagnosis of exclusion
Dactylitis is a type of ____ pain in SCD patients. Occurs in ___% of patients by 2 y.o. Clinical manifestations of Dactylitis? Tx?
Vasocculsive
40%
– Tender, erythematous,
edematous hands or feet
Tx:– Analgesics
– IVF
Splenic Sequestration is most common in SCD patients under age ___. How is diagnosis made? What’s the treatment?
2
Diagnosis- enlarged spleen, low H and H, high retic ct
Treatment
• IV fluids
• PRBC transfusion
• Chronic transfusion? Splenectomy?
Acute Chest Syndrome incidence is highest in SCD patients ages ____. ___% cause unknown, ___% infection
2-5 y.o.
45% cause unknown, 30%: infection
Peak incidence of stroke in SCD patients? Treatment and prevention of stroke in sickle cell patients?
• 10% risk in 1st 20 yrs of life; peak incidence:
4-8 y.o.
• Treatment: RBC transfusion
• Prevention: transcranial doppler 2-16 y.o.
30% of boys with SCD will experience ____ by 15 y.o.
priapism
Clinical manifestations and tx for priapism?
• Clinical manifestations: prolonged, painful
erection of penis (>4 hours) or stuttering course
(cluster of episodes)
Treatment – Analgesia – Reduction of engorgement • Pseudephedrine • Aspiration and irrigation
Aplastic Anemia in SCD patients is typically secondary to ____. Mostly what?
secondary to infection
Mostly parvovirus B19
Chronic, compensated hemolytic anemia is known as? Usual range __-___ g/dL; many function at 5-6
Chronic anemia
6-9
Acute anemia definition? How to manage?
• Definition:
– Hgb 2.0 g/dL below baseline
– Hgb <6.0 g/dL if baseline unknown
- Evaluate CBC and reticulocyte count
- Evaluate for etiology requiring urgent care
Megaloblastic Anemias - 2 types? common in children?
- Vitamin B12 deficiency
- Folate deficiency
- Combination of the two
- Very rare in children
Phases of hemostasis: primary hemostasis
vasoconstriction –> formation of platelet plug
Phases of hemostasis: secondary hemostasis
propagation of clotting process –> termination of clotting
Disorders of primary hemostasis (4) - Purpuric Disorders
- ITP
- Congenital thrombocytopenias
- Von Willebrand Disease
- Platelet function abnormalities
Disorders of secondary hemostasis (3) - Disorders of Coagulation
- Hemophilia A
- Hemophilia B
- Type 3 VWD
Purpuric Disorders (Primary Hemostasis) such as • ITP • Congenital thrombocytopenias • Von Willebrand Disease • Platelet function abnormalities
Describe the following….
- Petechiae
- Ecchymoses
- Soft tissue hematoma
- Joint hemorrhages
- Delayed bleeding
- Bleeding from superficial cuts
- Family hx of bleeding
- Sex of patient
- Petechiae: Y
- Ecchymoses: Y -small, many scattered
- Soft tissue hematoma: Rare
- Joint hemorrhages: Not usual
- Delayed bleeding: Rare
- Bleeding from superficial cuts: Common, persistent
- Family hx of bleeding: Rare
- Sex of patient: Mostly female
Disorders of Coagulation (Secondary hemostasis) such as
• Hemophilia A
• Hemophilia B
• Type 3 VWD
Describe the following….
- Petechiae
- Ecchymoses
- Soft tissue hematoma
- Joint hemorrhages
- Delayed bleeding
- Bleeding from superficial cuts
- Family hx of bleeding
- Sex of patient
- Petechiae: Not usual
- Ecchymoses: Common - 1 large or more
- Soft tissue hematoma: characteristic
- Joint hemorrhages: characteristic HALLMARK
- Delayed bleeding: common
- Bleeding from superficial cuts: uncommon
- Family hx of bleeding: common
- Sex of patient: mostly male
Initial screening for disorders of primary or secondary hemostasis: (4)
– CBC + peripheral blood smear
– PT/INR
– aPTT
– ?Fibrinogen activity
most common serious congenital
coagulation deficiencies? are they x-linked recessive?
Hemophilia A and B
yes
Pathophysiology of hemophilia
decreased levels of FVIII or FIX leads to dysfunctional clotting
___ is hallmark of hemophilia
Hemarthrosis
Hemophilia diagnosis
– Prolonged PTT, normal PT, INR and thrombin
– Factor VIII or IX activity level
– Genetic testing
Most common bleeding disorder among Caucasians? what’s the most common type?
Von Willebrand Disease
type 1:70-80%
Clinical manifestations of Von Willebrand Disease
• Clinical Manifestations
– Mucocutaneous bleeding
– Post-surgical/traumatic
bleeding
Most common cause of thrombocytopenia
secondary to increased platelet destruction
Immune Thrombocytopenic Purpura
Immune Thrombocytopenic Purpura is typically post___ in children
viral
Initial clinical manifestations of Immune Thrombocytopenic Purpura?
Sudden onset of petechiae
+/- purpura post viral illness
– Can progress to major hemorrhage from
mucosal sites
ITP: Treatment - observation, first line, second line?
– Observation: skin manifestations only
– First line: IVIG, corticosteroids, or WinRho
– Second line (chronic or refractory ITP): rituximab, immunosuppressive drugs, chemotherapy, thrombopoietin agonists, splenectomy?
A 2-day old boy has excessive bleeding after circumcision and labs reveal an aPTT time of 85 seconds and a factor VI activity level of <1%. The mother states that no one in the family has bleeding symptoms. Is this patient at risk for spontaneous bleeding in all joints?
yes
Most important proteins in plasma (2)
albumin, fibrinogen
If someone is dehydrated, ___ can go up - falsely elevated bc plasma volume is decreased so fraction of RBC seems higher than it is
HCT
Most important lab in the CBC when it comes to anemia?
MCHC - classifies as hypochromic, normochromic, hyperchromic
If hemoglobin is low, there would be ____ Retic count
elevated
If Retic is low and hemoglobin is low, you’re wondering
why isn’t the body compensating by making more blood cells?
Diagnostic findings consistent with beta-thalassemia intermedia and major are
hypochromia, microcytosis
