Hematology/Oncology Flashcards
Sites of RBC formation during prenatal life
2-8 weeks–yolk sac
8 weeks to 5 months–liver
5 months on–bone marrow
Causes of physiologic anemia of infancy
- Decrease in EPO production due to increase arterial oxygen content
- Shorted RBC lifespan in first 6-8 weeks (90 days vs 120 days)
Physiologic nadir–time and level
About 8-12 weeks of life, and about Hgb 9-11 (3-6 weeks and 7-9 in preterm infants)
Composition of hemoglobin types
Embryo: Gower 1--zeta and epsilon Gower 2--alpha and epsilon Portland--zeta and gamma Fetus: HbF--alpha and gamma (90% of Hb in 6 month fetus, 70% at birth, <2% in 1 year and older) Adult: HbA--alpha and beta HbA2--alpha and delta(2-3% of adult Hb)
Composition of Hb Barts
4 gamma chains–shows up on NBS, suggesting alpha thalassemia
Composition of HbH
4 beta chains–present in alpha thalassemia
Grouping of anemia mechanisms
1) Production defects (decreased EPO or bone marrow failure)
2) Maturation defects–cytoplasmic or nuclear
- Cytoplasmic with microcytic, hypochromic anemia–impaired Hgb synthesis, protoporphyrin deficiency (sideroblastic anemia), globin synthesis deficiency
- Nuclear with microcytic anemia–DNA synthesis defects (folate or B12 deficiency)
3) Survival defects–inherited or acquired
- Inherited–membrane cytoskeleton protein problems, metabolic enzyme problems, hemoglobinopathies
- Acquired–autoimmune, malaria, DIC, intravascular hemolysis
Anemia of chronic disease vs iron deficiency anemia
Anemia of chronic disease–low iron, low TIBC, low-normal transferring saturation, normal-high ferritin
Iron deficiency anemia–low iron, high TIBC, low transferrin saturation, low ferritin
What is the most common hypoproliferative anemia?
Anemia of chronic disease (impair iron utilization due to inflammatory mediators and decrease EPO)
What infants need iron supplementation and when?
- Breast-fed infants after 4 months of age (1mg/kg of elemental iron daily)
- Premature infants
What is the most common congenital GI cause of chronic blood loss?
Meckel diverticulum
What is the most common worldwide cause of chronic GI blood loss?
Hookworm infection (Necator americanus or Ancylostoma duodenale)
RDW in thalassemia trait vs iron deficiency anemia?
RDW is normal in thal trait, increased in iron deficiency anemia
Menzter Index–what is it? what is it used for?
MCV/RBC; >12 in iron deficiency (RBC count usually low); <11 in thal (RBC count normal or increased)
Treatment of iron deficiency anemia
1) PO iron–3-6 mg/kg/day of elemental iron
2) Correct underlying cause
Changes after starting iron therapy for iron deficiency?
1) Reticulocytosis starting in 3-5 days, peaking in 7-10 days.
2) Hgb increase 1-2 g/dL in 1st month
Syndromes with increased ALL risk (4)?
1) Down syndrome
2) Ataxia-telangiectasia
3) Bloom syndrome–short stature and increased homologous recombination
4) Fanconi anemia (more commonly AML)
Percentage of bone marrow blasts to diagnose acute leukemia?
> /= 25%
Breakdown of ALL lineage.
85% pre-B; 14% T-cell; 1% mature B-cell
Good prognostic indicators for ALL (4)?
1) Rapid responder
2) Hyperdiploidy (>50 chromosomes or DNA index >1.16)
3) t(12;21) (TEL-AML)
4) Female
Poor prognostic indicators for ALL (8)?
1) Age 10 years
2) Ph+ [t(9;22)]
3) t(4;11) (MLL gene)
4) WBC >50,000 at presentation
5) Mature B-cell lineage
6) T-cell lineage
7) Hypodiploidy
8) AA or hispanic ethnicity
Percentage of standard-risk ALL entering remission after induction?
> 95%
Predictive factor for 2nd remission in ALL?
Length of time of 1st remission
Conditions with increased AML risk (8)?
1) Down syndrome
2) Diamond-Blackfan syndrome
3) Fanconi anemia
4) Bloom syndrome
5) Kostmann syndrome (severe congenital neutropenia)
6) PNH
7) Neurofibromatosis
8) Exposure to ionizing radiation or etoposide