Hematologic Disorders I

Question 1

What are the 2 main components of blood

Answer 1

Plasma 55%

Formed elements 45%

Question 2

Role of erythrocytes
Production sites
Removal sites by MPS

Answer 2

Transport O2 and Co2
No nucleus, no mitochondria, non dividing.

Produced in vertebrae, pelvis, sternum, and ribs.
Removed by mononuclear phagocyte system in spleen, liver, and LN.

Question 3

Erythropoiesis is regulated by

Answer 3

O2 levels in blood. Stimulated by hypoxia.

Peritubular cells of the kidney produce erythropoietin, which induces RBC formation in the bone marrow. Takes 4 days.

Question 4

Growth requirements of Erythrocytes

Answer 4

Iron, protein, vitamins (folate and B12)

Deficiencies of iron and protein lead to reduced ability to carry O2.

Question 5

Normal hematocrit(RBC) level in men and women

Answer 5

Men: 42-50%
Women: 39-48%

Question 6

Anemia

Answer 6

Reduced O2 carrying capacity uses ischemia. Main cause is iron deficiency.

Question 7

3 main ways to get anemia

Answer 7

Reduced RBC production
Excessive blood loss due to trauma.
Increased RBC destruction.

Question 8

How many types of anemia. What are the two main types

Answer 8

400+ types
Iron deficiency anemia 50%
Anemia of chronic disease 33%

Question 9

How to classify anemia based on:

Cause

Size

Hemoglobin content

Answer 9

Cause: Hypoproliferative, hemolytic.

Size:
macrocytic due to B12 or folate deficiency.
Microcytic due to iron or lead deficiency.
Normocytic due to sickle cell disease.

Hemoglobin content:
Normochronic- normal amount. Sickle cell.
Hypochromic- iron or lead poisoning.

Question 10

Microcytic hypo chromic anemia is most likely due to

Answer 10

Iron deficiency.
most common type of anemia world wide and USA.

Main cause: iron unable to be recycled. May occur during pregnancy or slow Gi bleeds.

Could also be caused due to lead poisoning. Remove lead with chelation. Children at higher risk if they ingest paint chips.

Question 11

2 types of Macrocytic Normochromic anemia

Answer 11

1. Pernicious anemia. Due to reduced intrinsic factor causing Vit B12 deficiency. IF is a trasporter of B12 into bloodstream.
2. Folate deficiency anemia
   Folate, vit B9 deficiency. B9 is an enzyme involved with DNA synthesis of RBC. Associated with neural tube defects. Caused due to POOR DIET.

Question 12

Pernicious anemia is what type

Answer 12

Macrocytic normochromic anemia. Due to reduced intrisic factor.

Question 13

Folate deficiency anemia is what type of anemia.

Answer 13

Macrocytic normochromic anemia. Due to B9/folate deficiency from diet.

Question 14

3 types of normocytic normochromic anemia

Answer 14

1. Aplastic anemia (AA)
2. Hemolytic anemia
3. Anemia of Chronic Disease (ACD) 2nd most common cause of anemia in the word

Question 15

1 and 2 cause of anemia

Answer 15

1. Iron deficiency. Microcytic, hypo chromic.

2. Anemia of chronic disease due to chronic inflammatory disease. Normocytic, normochromic.

Question 16

Anemia of chronic disease

Answer 16

Normocytic, normochromic
2nd most cause of anemia behind iron deficiency.
Caused by chronic inflammatory disease. Tx underlying problem and EPO.

Question 17

Aplastic anemia

Answer 17

Normocytic, normochromic anemia. Bone marrow is replaced with fibrous, fatty tissue. Abrupt onset of low blood cell counts causes pancytopenia. Increases infections and hemorrhages.
75% IDIOPATHIC.
Could also be caused by antibiotics. Chloramphenicol.

Question 18

Hemolytic anemia

Answer 18

Normocytic, normochromic anemia. Premature destruction of RBC. Fatigue, jaundice, red/brown urine.

Two types:

1. Intrinsic: inherited deficiencies such as sickle cell or thalassemia. more common.
2. Extrinsic: Autoimmune or medications such as cephalosporins. Damage to circulating RBC.

Question 19

Hemoglobinopathies

Answer 19

Inherited disorders affecting hemoglobin formation. Such as sickle cell anemia or thalassemia.

Question 20

Sickle cell genotype

Answer 20

AS (70%)
A is normal
S is sickle

AS and AC are recessive.
SS, SC, CC

Question 21

Most common inherited blood disorder

Answer 21

Sickle cell anemia.
Normocytic normochromic. Autosomal recessive. Abnormal hemoglobin synthesis.
Due to point mutation.
Main result: Ischemia, organ damage, microvascular occlusion.

Question 22

5 stages of sickle cell retinopathy

Answer 22

1. Peripheral arteriolar occlusions.
2. Peripheral AV anastomoses
3. Sea fan neovascularization
4. Vitreous hemorrhage
5. Traction or detachement

Question 23

Highest risk of sickle cell retinopathy

Answer 23

SC > SS > AS

Question 24

Thalassemias

Answer 24

Microcytic hypo chromic

Inherited hemoglobinopathy.
Absent or reduced globing chains in hemoglobin. Cycling of RBC does not occur.

2 main types:
Alpha- less severe, more common.
Beta- severe, fatal in childhood.

Question 25

Ocular manifestations of anemia

Answer 25

Rare unless pt is anemic and has low platelet levels too.

Conjunctival pallor. 75% of cases if RBC is less than 50% of normal.
Anemic retinopathy. Hemorrhages, CWS, roth spots.
ONH palor.

Question 26

Polycythemia

Answer 26

Increase in RBC mass.
>51% hematocrit in men
> 48% hematocrit in women.

1. Primary. Polycythemia Vera. 60% most common. Neoplastic. Proliferative disease of the bone marrow.
2. Secondary. Increased EPO due to disease. COPD, sleep apnea, CHF.
3. Relative polycythemia. Due to dehydration. Increases thrombosis risk due to stasis.

Question 27

Polycythemia Vera.

Answer 27

Neoblastic. BM cancer or gene mutation at JAK2 locus. Found in 95% of cases.
50% risk of acute myeloid leukemia (AML) over 20 years.

Question 28

Ocular manifestations of polycythemia.

Answer 28

Transient vision loss (40%)

Question 29

What causes leukocytosis or leukopenia

Answer 29

high- infectino

low- immunosuppression

Question 30

What causes polycythemia or anemia

Answer 30

Polycythemia vera or chronic hypoxia.

Nutritional deficiency.

Question 31

What causes thrombocytosis or thrombocytopenia

Answer 31

Tissue damage or infection. Platelet count increases with damage.
Immune system