Anemia and Red Cell Disorders

Question 1

Causes of microcytic anemia

Answer 1

Iron deficiency anemia

Thalassemia

Question 2

Causes of macrocytic anemia

Answer 2

B12, folate deficiency

Reticulocytosis

Question 3

Lab of hemolytic anemia:

Answer 3

Increased indirect bilirubin
Increased lactate dehydrogenase: released from RBC in hemolysis
Decreased haptoglobin: Free hemoglobin binds to haptoglobin cleared by liver

Question 4

Morphology of hemolytic anemia:

Answer 4

Increased erythroid precursors in marrow
Increased polychromasia (reticulocytosis) 
Anisocytosis: variation in size

Question 5

Labs for intravascular hemolysis:
Plasma hemoglobin
Haptoglobin
Urine hemoglobin and hemosiderin

Answer 5

Increased plasma hemoglobin
Decreased haptoglobin
Urine positive for hemoglobin and hemosiderin

Question 6

Labs for extravascular hemolysis:

Answer 6

Urine negative for hemoglobin and hemosiderin

+/- plasma hemoglobin

Question 7

Intravascular hemolysis

Answer 7

RBC destroyed in blood veseels from mechanical damage, vascular damage or some type of immune mediated damage

Question 8

Extravascular hemolysis

Answer 8

Red cells destroyed in the macrophages, primarily in the spleen

Question 9

Hereditary spherocytosis
Genetics:
Results in:

Answer 9

Autosomal dominant: most common mutation in ankyrin

Decreased spectrin, ankyrin, band 3 in RBC membrane –>Decreased membrane stability –> removed by spleen

Question 10

G6PD Deficiency
Genetics:
Results in:
Morphology:

Answer 10

X-linked: G6PD A-, G6PD Mediterranean

Can’t produce reduced glutathione due to lack of NADPH –> can’t handle oxidative stress –> hemolysis

Blister cells

Question 11

Sickle cell disease caused by:

Causes:

Answer 11

Valine is substituted for glutamic acid at the 6 position in the beta globin chain

Repeated splenic infarction leads to auto-splenectomy
Howell Jolly bodies in peripheral blood
High platelet count
Presence of S hemoglobin and absence of hemoglobin A

Question 12

Hemoglobinopathies =

Associated with:

Answer 12

Disorder of hemoglobin syntheisis

Target cells

Question 13

Thalassemia =

Produces ____ type of anemia

Answer 13

Disorders of globin chain synthesis

hypochromic/microcytic anemia

Question 14

Alpha thalassemia caused by:

4 gene deletion –>

Answer 14

gene deletion

Intrauterine fetal death

Question 15

Beta thalassemia caused by:

Labs:

Treament:

Answer 15

point mutations –> excess alpha chains precipitate –> membrane damage

Elevated hemoglobin A2 level

Frequent tranfusions –> may develop iron overload

Question 16

Immune hemolytic anemia =

Lab:

Answer 16

Antibody develops against part of red cell membrane –> Ab + part of membrane removed by spleen –> spherocytes –> removed by spleen

Positive Direct antiglobulin test

Question 17

Characteristic feature of fragmentation hemolytic anemia

Answer 17

schistocytes

Intravascular hemolysis

Question 18

Microangiopathic hemolytic anemia =

Ex:

Answer 18

Microvascular thrombi cause fragmentation of erythrocytes and consumption of platelets

THrombotic thrombocytopenic purpura, DIC

Question 19

Reticulocytes are not increased in:

Answer 19

Anemia of decreased production:

Megaloblastic anemia

Question 20

Megaloblastic anemia =

Morphology:

Answer 20

Impaired DNA synthesis due to B12 or folate deficiency

Oval macrocytes, hypersegmented neutrophils
Hypercellular bone marrow with increased red cell precursors but never get into peripheral blood

Question 21

B12 absorbed in ___, requires ___

Answer 21

Terminal ileum, intrinsic factor

Question 22

B12 deficiency seen in:
Mostly due to:
Labs:

Answer 22

strict vegans
Pernicious anemia: autoimune disorder w/ ab to IF
Has neurologic defects

Low serum vit B12
Increased homocysteine
Increased methymalonic acid

Question 23

Folate deficiency

Labs:

Answer 23

No neurologic defects

Decreased serum and red cell folate levels
Increased homocysteine
Normal methylmalonic acid

Question 24

Iron deficiency anemia
Morphology:
Labs:

Answer 24

Most common disorder

Hypochromoic, microcytic anemia: increased central pallor

**Decreased serum ferritin: total body iron stores
Decreased serum iron
Increased total iron binding capacity: measure transferrin
Decreased iron saturation

Question 25

Anemia of chronic inflammation | Type:

Answer 25

mild, normocytic/mildly microcytic anemia Increased inflammatory cytokines --> increased hepcidin (iron regulatory hormone) --> decreased iron absorption form GI, increased storage in macrophages --> iron deficiency

Question 26

Increased ferritin

Answer 26

Anemia of chronic disease

Question 27

Decreased total iron binding capacity

Answer 27

Anemia of chronic disease

Question 28

Decreased ferritin

Answer 28

Iron deficiency anemia

Question 29

Increased total iron binding capacity

Answer 29

Iron deficiency anemia

Question 30

Decreased iron stores

Answer 30

Iron deficiency anemia

Question 31

Increased iron stores

Answer 31

Anemia of chronic disease

Question 32

Aplastic anemia = Findings: Caused by:

Answer 32

syndrome of marrow failure with pancytopenia Normocytic, mildly macrocytic anemia Leukopenia Thrombocytopenia Fatty replacement of marrow Suppression of stem cell function by activated T cells

Question 33

Myelophthisic anemia =

Answer 33

from marrow replacement caused by: Metastatic cancer Leukemia/lymphoma Fibrosis

Question 34

Anemia of renal failure/uremia caused by

Answer 34

decrease erythropoietin stimulation of red cells

Question 35

Polycythemia =

Answer 35

too many RBCs

Question 36

Secondary polycythemia caused by:

Answer 36

increase in EPO production | High altitude, pulmonary disease, congenital heart disease

Question 37

Primary polycythemia (Polycythemia vera) caused by: Findings: Treatment:

Answer 37

mutation of JAK2 V617F --> proliferation of hematopoietic cells in marrow Hypercellular bone marrow w/ increased erythroid precursor High hematocrit Phlebotomy