Hematopathology (Schoenwald)

Question 1

What is anemia?

Answer 1

decrease in red blood cells

Question 2

What are the 3 mechanisms that can lead to anemia?

Answer 2

blood loss- acute or chronic
decreased production of RBCs
increased destruction of RBCs (hemolysis)

Question 3

How is anemia evaluated?

Answer 3

size of the red blood cell (MCV) and hemoglobin concentration (MCHC)

Question 4

What are examples of blood loss that lead to anemia?

Answer 4

acute- trauma

chronic- GI malignancy, menstrual bleeding

Question 5

What are external factors that lead to increased destruction of red blood cells?

Answer 5

antibody-mediated transfusion reaction or erythroblastosis fetalis 
autoimmune 
trauma to RBC 
infection 
sequestration in spleen

Question 6

What are hereditary internal factors that lead to increased destruction of RBCs?

Answer 6

cytoskeleton defect- hereditary spherocytosis
structurally abnormal hgb- sickle cell, thalassemia
enzyme deficiency- G6PD

Question 7

What is an acquired defect that leads to increased destruction of RBCs?

Answer 7

paroxysmal nocturnal hemoglobinuria

Question 8

What is paroxysmal nocturnal hemoglobinuria?

Answer 8

red cells are more prone to lysis by complement (complement-regulating proteins CD55 and CD59 are deficient)

Question 9

What is the defect in paroxysmal nocturnal hemoglobinuria?

Answer 9

acquired defect in the gene for phophatidylinositol class A (PIG-A)

Question 10

What does paroxysmal nocturnal hemoglobinuria result in?

Answer 10

venous thrombosis- hepatic, portal, mesenteric, and cerebral veins

Question 11

What are the clinical signs of paroxysmal nocturnal hemoglobinuria?

Answer 11

episodic hemoglobinuria, 1st morning urine

Question 12

What are examples of what can lead to decreased production of RBCs?

Answer 12

disturbance of stem cells
defective heme production
defective DNA production
destruction of bone marrow

Question 13

What is an example of disturbance of stem cells, leading to a decreased production of RBCs?

Answer 13

aplastic anemia

Question 14

What are examples of defective heme production, leading to a decreased production of RBCs?

Answer 14

iron deficiency

thalassemia

Question 15

What is an example of defective DNA production, leading to a decreased production of RBCs?

Answer 15

vitamin B12 and folic acid deficiencies

Question 16

What is an example of destruction of bone marrow, which leads to a decreased production of RBCs?

Answer 16

metastatic tumor

Question 17

What are the sites of removal of the RBC from circulation?

Answer 17

extravascular- phagocytic systems of spleen and liver

intravascular- destruction of RBC in the vessel

Question 18

What are complications of extravascular RBC removal?

Answer 18

hemosiderin deposition in organs

jaundice and gallstones (results from elevated unconjugated bilirubin associated with hemolysis)

Question 19

What are complications of intravascular RBC removal?

Answer 19

acute tubular necrosis due to hemoglobinemia

jaundice, gallstones can occur due to increased unconjugated bilirubin

Question 20

What are the lab findings in hemolysis of RBCs?

Answer 20

decreased RBCs

increased bilirubin in the circulation from the breakdown of RBCs

Question 21

spherocytes morphology

Answer 21

hereditary spherocytosis and immune hemolysis

Question 22

schistocytes morphology

Answer 22

TTP and HUS

Question 23

target cells morphology

Answer 23

hemaglobinopathies

Question 24

teardrops morphology

Answer 24

myelofibrosis

Question 25

sickle cell morphology

Answer 25

sickle cell, thalassemia minor with sickle cell

Question 26

Rouleaux morphology

Answer 26

"stacking of coins" due to increased globes or decreased albumin (multiple myeloma)

Question 27

What is the clinical presentation of anemia?

Answer 27

pale skin, fatigue, shortness of breath, chest pain, syncope, dizziness

Question 28

What labs would you order if you suspect anemia?

Answer 28

MCV | reticulocyte count

Question 29

What is an increased reticulocyte count indicative of?

Answer 29

bone marrow is intact and able to produce RBC in acute blood loss of hemolysis

Question 30

What is a decreased reticulocyte count indicative of?

Answer 30

primary bone marrow disorder or deficiency in building blocks- iron, b12, or folate

Question 31

microcytic is an MCV...

Answer 31

less than 80

Question 32

normocytic is an MCV...

Answer 32

80-100

Question 33

macrocytic is an MCV....

Answer 33

greater than 100

Question 34

What are examples of microcytic anemias?

Answer 34

iron deficiency thalassemia late stage anemia of chronic disease

Question 35

What is iron deficiency anemia mostly due to in the US?

Answer 35

GI blood loss of menstrual blood loss

Question 36

Outside of the US, what is the most common cause of iron deficiency anemia?

Answer 36

poor nutrition

Question 37

Other than GI blood loss, menstruation, or poor nutrition, what else causes iron deficiency anemia?

Answer 37

malabsorption or increased demand such as in pregnancy

Question 38

What labs would you expect to see in iron deficiency anemia?

Answer 38

``` decreased ferritin decreased serum iron decreased iron stores in bone marrow increased total iron binding capacity (TIBC) increased RDW decreased transferrin saturation ```

Question 39

How is transferrin saturation calculated?

Answer 39

ratio of serum iron to TIBC

Question 40

What is normal transferrin saturation?

Answer 40

normal >20%

Question 41

What value would you expect to see for transferrin saturation in iron deficiency anemia?

Answer 41

less than 1-%

Question 42

What is thalassemia?

Answer 42

deficient production of hemoglobin due to mutation or complete loss of globin chain- there are 4 copies of the alpha globulin chain and 2 copies of the beta globulin

Question 43

What is alpha thalassemia due to?

Answer 43

complete loss of one or more of the 4 copies of the alpha globulin chain gene

Question 44

What is seen in a thalassemia carrier?

Answer 44

loss of one copy of gene is silent

Question 45

What is seen in alpha thalassemia trait?

Answer 45

loss of 2 copies, asymptomatic, but MCV is low

Question 46

What is seen in alpha thalassemia that results in HbH disease?

Answer 46

loss of 3 copies- marked anemia

Question 47

What is seen in alpha thalassemia that results in hydrops fetalis?

Answer 47

loss of 4/4 copies (stillborn)

Question 48

What populations is alpha thalassemia prevalent in?

Answer 48

africans and asians

Question 49

Does alpha thalassemia usually require blood transfusions?

Answer 49

no

Question 50

What is beta thalassemia?

Answer 50

malfunction of gene due to mutation which results in complete loss of the hemoglobin protein

Question 51

What population is beta thalassemia seen in?

Answer 51

mediterranean descent

Question 52

What is the result of beta thalassemia?

Answer 52

alpha chains are insoluble and result in intravascular hemolysis and ineffective erythropoiesis

Question 53

Does major beta thalassemia require blood transfusions?

Answer 53

yes, due to severe anemia

Question 54

What is the onset of age of major beta thalassemia?

Answer 54

usually onset after 6 months of age due to loss of Hgb F and transition to Hgb A

Question 55

What sxs are seen in major beta thalassemia?

Answer 55

skeletal abnormalities due to bone marrow expansion

Question 56

Does minor beta thalassemia usually require blood transfusions?

Answer 56

no

Question 57

What is disproportionate in minor beta thalassemia?

Answer 57

Hgb and MCV disproportionate- hgb 10/ MCV 55

Question 58

What labs would you expect to see in beta thalassemia?

Answer 58

decreased MCV decreased hgb anisocytosis poikilocytosis (mircocytes, targets)

Question 59

What diseases is it common to see anemia of chronic disease?

Answer 59

lung carcinoma Hodgkin lymphoma RA infection- TB

Question 60

Initially, anemia of chronic disease is _____, but in late stage it can be _____.

Answer 60

normocytic, microcytic

Question 61

What labs would you expect to see in anemia of chronic disease?