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Flashcards in Heme Deck (367)
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1

Normoblasts

Nucleated RBCs

2

Reticulocytes

When nucleated RBCs lose their nucleus (5-7 days)

3

What causes left shift of O2 binding

Increase pH
Decrease DPG/Temp

4

What causes right shift of O2

Decreased pH
Increased DPG/TEMP

5

What is the major Hemoglobin structure for adults

HbA (alpha/beta) 95%

6

Why are RBCs binconcave in shape

Enables max O2 saturation
Allows passage through small capillaries and splenic sinusoids

7

Anemia

Lower than normal total circulating red cell mass

8

Mean cell volume

MCV
Volume of RBC
Femtoliters

9

Mean cell hemoglobin

MCH
Average content of Hb
Picograms

10

Mean cell hemoglobin concentration

MCHC
Concentration of Hb in given packed RBCs

11

Red cell distribution

RDW
Coefficient of variation of RBC volume

12

Anemia due to acute hemorrhage, what is the immediate concern

Hypovolemia

13

Are the majority of hemolytic anemias found intravascular or extravascular

Extravascular

14

Intravascular hemolysis Causes

Complement fixation: BIGGEST! think of blood mismatching
Mechanical injury
Infections/ intracell parasites, toxins

15

What happens to RBCs in extravascualr hemolysis

RBCs rendered less deformable
RBCs thought as foreign

16

Lab: PB- normochromic, normocytic anemia, increased reticulocytes
BM- erythroid hyperplasia
Serum: Increased unconjugated bili, increase LDH, low haptoglobin

Hemolytic anemia

17

Urine: hemosiderinuria, +/- hemoglobinuria

Intravascular hemolysis

18

Hereditary intrinsic RBC defects

Spherocytosis: membrane defect
G6PD: Enzyme defect
Sickle: hemoglobin defect

19

Acquired extrinsic RBC defects

Immune mediated damage
Nonimmune mediated damage
Sequestration- hypersplenism

20

Who has highest incidence of spherocytosis

N. Europeans

21

What is the genetic pattern for spherocytosis

AD

22

What is the lifespan of RBCs in spherocytosis

10-20 days

23

What are the proteins affected in spherocytosis

Ankyrin (75%)
Band (20%)
Ankyrin, spectrin, band 4.1, band 4.2

24

Why is there splenomegaly in spherocytosis

Deformed RBC (more spherical) unable to traverse splenic sinusoids, phago by splenic macrophages

25

Tx of spherocytosis

Splenectomy

26

mild to chronic hemolytic anemia
Induced aplastic/ hemolytic crisis

hereditary spherocytosis

27

What is the one test for spherocytosis

Osmotic fragility test
In 65% of patients RBCs lyse prematurely when exposed to hypotonic salt solutions

28

G6PD is in which cycle

Hexose monophosphate shunt (glutathione metabolism)

29

What are the G6PD variants which cause disease

A: 10% africans
Mediteranian: mostly middle east

30

G6PD is protective against

P. Falciparum malaria