Introduction to Hematology

Question 1

What is hematopoiesis?

Answer 1

the process by which all blood cells differentiate (along different lines of development) from hematopoietic stem cells into all the different types of blood cells

Question 2

What is hemolysis?

Answer 2

premature breakdown and destruction of RBCs

Question 3

What is erythropoiesis?

Answer 3

process by which RBCs are produced

usually stimulated by low O2

Question 4

What is Anemia?

Answer 4

a decrease in circulating RBCs (red blood cell mass) due to

• increased destruction
• decreased production
• loss (bleeding)

often related to Fe deficiency

Question 5

What is hemostasis? What 3 factors are involved?

Answer 5

Process that causes bleeding to stop through the interaction of
1. platelets
2. enothelium
3. coagulation proteins
carefully regulated (only with injuries// not in circulating blood)

Question 6

What is thrombosis?

Answer 6

pathogenic clotting of blood
no longer balanced by inhibitory factors and fibrinolytic system
(DVT)
sx can be sweling or backflow

Question 7

What is the basic shape/composition of an erythrocyte?

Answer 7

biconcave disc
- high surface are to volume ratio
- deformable
no nucleus or mitochondria (lost before leave marrow) 
120 day lifespan
dependent on anaerobic metabolism

Question 8

What are the 5 types of white blood cells?

Answer 8

1. Lymphocytes
2. Neutrophils
3. Monocytes
4. Eosinophils
5. Basophils

Question 9

Where do the malignant cells originate in leukemia?

Answer 9

in the bone marrow

Question 10

Where do the malignant cells in lymphoma originate?

Answer 10

extramedullary (outside bone marrow)
ususally involve:
- lymph nodes
- other lymph organs

Question 11

What does an acute classification mean in leukemia?

Answer 11

malignant cells are immature in terms of differentiation

- rapid clinical progression without intervention

Question 12

What does a chronic classification mean in leukemia?

Answer 12

malignant cells are more mature in terms of differentiation

- disease follows indolent (lazy/ slow) course

Question 13

What is lymphoid leukemia compared to myeloid leukemia?

Answer 13

Lymphoid- arrises from lymphocytic lineage
myeloid - arises from any other cell type in marrow

usually malignant cell shares surface markers or cell products with normal counterpart leading to a specific classification

Question 14

What are platelets?

Answer 14

cellular component of blood that is responsible for homeostasis (clotting)

Question 15

Where do platelets come from?

Answer 15

Megakaryocyte

[megakaryblast -> promegakaryocyte -> megakaryocyte -> metamegakaryocyt -> thrombocyte (platelet)]

Question 16

How do platelets function?

Answer 16

Interact with endothelim and blood coagulation factors at the site of an injury to form clot and repair damage

Inhibitory factors and fibrinolytic system balances this action by breaking down formed clots

Question 17

What components of blood are in the buffy coat?

Answer 17

WBCs

platelets

Question 18

What components of blood are in the plasma?

Answer 18

proteins
lipids
salts 
carbohydrates 
enzymes

Question 19

What component of blood is in the hematocrit?

Answer 19

RBCs

Question 20

In terms of survival, how does the lace of a nucleus affect RBCs?

Answer 20

They cannot easily adapt to changes in environment

- die if changes are too extreme

Question 21

What substrates are important for erythropoiesis?

Answer 21

B12
Folate
Fe
erythropoietin

Question 22

Where is erythropoietin produced?

Answer 22

Kidney

Question 23

What causes spherocytes?

Answer 23

Spleen pinches off abnormal portions of RBC membrane, gradually reducing surface area to volume ratio

Question 24

What type of anemia is caused by decreased G6PD? What is the resulting cell morphology?

Answer 24

acute hemolytic anemia with stress
- reduced capacity to prevent cellular damage by oxygen radicals
(no mitochondria means cells rely on anaerobic metabolism for energy)

Heinz bodies are removed from cell by spleen =>
Bite cells

Question 25

What cells are the “foot soldiers of the blood”?

Answer 25

neutrophils
aka - PMNs (polymorphonuclear cells)

finding, ingesting and digesting bacteria,debris and dead tissues

they sense pathology and kill (endocytose) cause of infection-> release toxins to kill

Question 26

What is a Reed-Sterhberg cell a classic sign of?

Answer 26

Hodgkin lymphoma

Reed-Sternberg cell: 
from B lymphocytes 
- large, multinucleated
- eosinophilic inclusion-like nuclei
- Owl's eye appearance