HEMOGLOBINOPATHIES

Question 1

• Most common genetic diseases, affecting approximately 7% of world’s population
• Qualitative defect of hemoglobin due to altered amino acid sequence within the globin chains

Answer 1

HEMOGLOBINOPATHIES

Question 2

HEMOGLOBINOPATHIES:
Confirmatory test:

Answer 2

HPLC
Hb Electrophoresis

Question 3

Hb Electrophoresis
_____ (pH 8.4)
_____ (pH 6.0 - 6.2)

Answer 3

Cellulose acetate
Citrate agar

Question 4

All hemoglobin will migrate towards anode

Answer 4

Cellulose Acetate Agar

Question 5

Cellulose Acetate Agar
Normal result:

Answer 5

A, A2, F

Question 6

Normal hemoglobin that is fastest/ nearest to anode

Answer 6

A

Question 7

Normal hemoglobin that is fastest/ nearest to anode is A followed by __

Answer 7

F

Question 8

Slowest to migrate

Answer 8

A2

Question 9

Cellulose Acetate Agar
Abnormal hemoglobins:

Answer 9

S, D, G, C, E, O

Question 10

Performed when you want to separate hemoglobin S,D,G,C,E,O from S

Answer 10

Citrate Agar

Question 11

S is separated from _ and _

Answer 11

D
G

Question 12

C is separated from _ and _

Answer 12

E
O

Question 13

Qualitative defect of hemoglobin

Answer 13

Hemoglobinopathies

Question 14

Quantitative defect of hemoglobin
(absent or lacking globin
chain)

Answer 14

Thalassemia

Question 15

Valine replaces glutamic acid at the 6th position of the beta chain

Answer 15

HEMOGLOBIN S

Question 16

HEMOGLOBIN S:
____ replaces Glutamic acid at the ___ position of the ___ chain

Answer 16

Valine
6th
beta

Question 17

Sickle Cell trait -

Answer 17

Hb As

Question 18

• Generally asymptomatic or has mild symptoms only
• Normal RBC morphology, with the exception of a few target cells

Answer 18

Sickle Cell trait - Hb As

Question 19

• Most common form of hemoglobinopathy
• Patients are either homozygotes (SS) or compound heterozygotes (SC, SE, S-B-thal)

Answer 19

Sickle cell disease

Question 20

HEMOGLOBIN S:
Pathophysiology:
- Less soluble forming ____ or liquid crystals and causes sickling of RBCs
- ____ blood viscosity and ______ slow the blood flow
- Occlusion of capillaries and arterioles by sickled RBCs and infarction of
surrounding tissue
- _______ damages the membrane channels in RBC

Answer 20

tactoids
Increased
sickle cell formation
Hb S polymerization

Question 21

HEMOGLOBIN S
Pathophysiology:
* Less soluble forming tactoids or liquid crystals and causes sickling of RBCs
___% O2 saturation among homozygotes
___% O2 saturation among heterozygotes

Answer 21

< 85%
< 40%

Question 22

Hallmark of SCD, which accounts for most hospital and emergency department visits

Answer 22

Vaso occlusive crisis

Question 23

T or F
HEMOGLOBIN S:
Painful episodes manifest often in bones, lungs, liver, spleen, eyes, CNS, urinary tract

Answer 23

T

Question 24

HEMOGLOBIN S
Clinical Features:
- Sudden trapping of blood in the spleen, which leads to a rapid decline in hemoglobin
- Repeated splenic infarcts produce scarring resulting in diminished splenic tissue, abnormal function or gradual loss of splenic function
(autosplenectomy)

Answer 24

Splenic sequestration and infarcts

Question 25

HEMOGLOBIN S Clinical Features: - Acute infections are common causes of hospitalization and have been the most common causes of death, especially in the first 3 years of life

Answer 25

Bacterial infections

Question 26

HEMOGLOBIN S Clinical Features: Most common life-threatening hematologic complications and are usually associated with parvovirus infection

Answer 26

Aplastic episodes (BM failure)

Question 27

HEMOGLOBIN S Laboratory Screening Tests: Slide method (+) result: Sickling of RBCs

Answer 27

2% Sodium metabisulfite test

Question 28

HEMOGLOBIN S Laboratory Screening Tests: Tube method (+) result: Turbidity

Answer 28

Dithionite solubility test

Question 29

2% Sodium metabisulfite test - Slide method (+) result:

Answer 29

Sickling of RBCs

Question 30

Dithionite solubility test - Tube method (+) result:

Answer 30

Turbidity

Question 31

LYSINE replaces glutamic acid at the 6th position of beta chain

Answer 31

HEMOGLOBIN C

Question 32

HEMOGLOBIN C: ____ replaces glutamic acid at the __ position of ____ chain

Answer 32

LYSINE 6th beta

Question 33

Found almost exclusively in the African American population

Answer 33

HEMOGLOBIN C

Question 34

Most common non-sickling Hb variant encountered in the United States

Answer 34

HEMOGLOBIN C

Question 35

Hb C forms polymers intracellularly (short, thick crystals); increased in number of _____

Answer 35

target cells

Question 36

hexagonal crystals/”bar of gold” appearance

Answer 36

Thick crystals

Question 37

associated with liver disease, Thalassemia, Hgb C disease

Answer 37

Target cells

Question 38

T or F Hgb C is milder disease compared with SCD since vaso-occlusive crisis does not occur

Answer 38

T

Question 39

LYSINE replaces glutamic acid at the 26th position of beta chain

Answer 39

HEMOGLOBIN E

Question 40

HEMOGLOBIN E: ___ replaces glutamic acid at the ____ position of __chain

Answer 40

LYSINE 26th beta

Question 41

The homozygous state (Hb EE) manifests as a mild anemia with microcytes and target cells

Answer 41

HEMOGLOBIN E

Question 42

LYSINE replaces glutamic acid at the 121st position of beta chain

Answer 42

HEMOGLOBIN O-ARAB

Question 43

HEMOGLOBIN O-ARAB: ___ replaces glutamic acid at the ____ position of ___ chain

Answer 43

LYSINE 121st beta

Question 44

Rare disorder found in Kenya, Israel, Egypt, and Bulgaria

Answer 44

HEMOGLOBIN O-ARAB

Question 45

TYROSINE replaces histidine in the α, β, or γ chains

Answer 45

HEMOGLOBIN M

Question 46

HEMOGLOBIN M: _____ replaces ___in the α, β, or γ chains

Answer 46

TYROSINE histidine

Question 47

iron in the ferric state (Fe3+) and is unable to carry oxygen, which produces cyanosis

Answer 47

HEMOGLOBIN M

Question 48

HEMOGLOBIN M: iron in the ____ state and is unable to carry oxygen, which produces _____

Answer 48

ferric cyanosis

Question 49

GLUTAMINE replaces glutamic acid at the 121st position of beta chain

Answer 49

HEMOGLOBIN D

Question 50

HEMOGLOBIN D: _____ replaces glutamic acid at the ___ position of ____ chain

Answer 50

GLUTAMINE 121st beta

Question 51

LYSINE replaces asparagine at the 68th alpha chain

Answer 51

HEMOGLOBIN G

Question 52

HEMOGLOBIN G: ____ replaces asparagine at the ____ ____chain

Answer 52

LYSINE 68th alpha