3: Haematology - Haemaglobinopathies in Children

Question 1

What is thalassemia

Answer 1

Defect in genes encoding globing chains - causing defect globing chains

Question 2

What is a-thalassemia

Answer 2

Defect in one or more genes encoding a-globin genes

Question 3

In which two ethnicities is a-thalassemia more common

Answer 3

Asian

African

Question 4

what is the inheritance pattern of a-thalassemia

Answer 4

Autosomal recessive

Question 5

explain aetiology of a-thalassemia

Answer 5

Deletion of at least one of four-alleles which encode two a-globin chains on chromosome 16

Question 6

what chromosome is impacted in a-thalassemia

Answer 6

Chromosome 16

Question 7

what is a thalassemia minima

Answer 7

a-/aa

Deletion one gene

Question 8

how will a thalassemia minima present

Answer 8

Silent carrier

Question 9

what defect is present in a thalasemia minor

Answer 9

a-/a- or aa/–

Question 10

what deletion in a-thalasemia minor is more common in Africans

Answer 10

Trans (a-/a-)

Question 11

what deletion in a-thalasemia minor is more common in Asians

Answer 11

Cis (aa/–)

Question 12

what is trans

Answer 12

Deletion on different chromosomes

Question 13

what is cis

Answer 13

Deletion on same chromosome

Question 14

how does a-thalassemia minor present

Answer 14

Mild haemolytic anaemia

RBC and RDW in normal range

Question 15

what is HbH Disease

Answer 15

a-/–

Question 16

how dies HbH disease present

Answer 16

Jaundice
Anaemia
Hepatosplenomegaly

Question 17

what is Hb-Barts hydrops fatalis

Answer 17

Deletion all 4 alpha-alleles of a-globin chains

Question 18

what is hydrops fatalis

Answer 18

Collection of fluid in two or more compartments

Question 19

what does Hb-Barts hydrops fatalis cause

Answer 19

In-utero death

Question 20

how will a-thalasemia present on FBC

Answer 20

Microcytic Hypochromic Anaemia

Question 21

how can thalasemia be differentiated from IDA

Answer 21

Normal RDW

Question 22

What can be seen on peripheral blood smear in thalassemia

Answer 22

Teardrop cells

Question 23

What is confirmatory-test for thalasemia

Answer 23

Hb electrophoresis

Question 24

How is a-thalasemia minima treated

Answer 24

No Rx

Question 25

How is a-thalasemia minor treated

Answer 25

Iron | Folate

Question 26

How is HbH treated

Answer 26

Iron, Folate Transfusion Allogenic stem cell transplant - curative

Question 27

What is B thalasemia

Answer 27

Defect in genes encoding B-globin chains

Question 28

How many genes encode B-globin chains

Answer 28

Two

Question 29

How many variations of B-thalasemia are there

Answer 29

Two Diseases

Question 30

What ethnicity is B-thalasemia more common in

Answer 30

Medeteranian

Question 31

What is the inheritance pattern of B-thalasemia

Answer 31

Autosomal recessive

Question 32

When will b-thalasemia symptoms manifest and why

Answer 32

6-months Initially a foetus is born with foetal Hb (2-alpha and 2-gamma chains). This gradually decreases and adult Hb is produced (2-alpha, 2-beta)

Question 33

What is B thalassemia minor

Answer 33

B/-

Question 34

How does B thalassemia present

Answer 34

Mild anaemia | Asymptomatic

Question 35

What is B thalassemia major

Answer 35

-/-

Question 36

How does B-thalasemia major present

Answer 36

- Severe anaemia - Secondary growth dysfunction - Extramedullary enlargement

Question 37

How will FBC present in thalasemia

Answer 37

Microcytic hypochromic anaemia

Question 38

How can anaemia in thalasemia be differentiated from IDA

Answer 38

RDW will be normal

Question 39

What is a sign of haemolysis in thalasemia

Answer 39

Low haptoglobin High LDH High reticulocytes

Question 40

What can be seen on blood smear in thalassemia

Answer 40

Teardrop cells

Question 41

What is confirmatory test for thalasemia

Answer 41

Hb Electrophoresis

Question 42

How is B-thalassemia major treated

Answer 42

Regular blood-transfusions every 3-4W

Question 43

What is risk of frequent blood transfusions

Answer 43

Iron overload

Question 44

What is the only definitive management of B-thalasemia

Answer 44

Allogenic bone marrow transplant

Question 45

What does ITP stand for

Answer 45

Idiopathic (Immune) thrombocytopenia purpura

Question 46

What are the three types of ITP

Answer 46

- Acute - Chronic - Evans

Question 47

When is acute ITP seen

Answer 47

Young children following viral infection. It resolves in 1-2W

Question 48

When is chronic ITP seen

Answer 48

Middle-age adults: presents as a relapsing and remitting course

Question 49

What is Evan's syndrome

Answer 49

ITP and autoimmune haemolytic anaemia

Question 50

What age does acute ITP occur

Answer 50

2-5 years

Question 51

What causes ITP

Answer 51

Autoantibodies to glycoprotein IIa and IIb

Question 52

What precedes ITP

Answer 52

Viral Infection

Question 53

How does ITP present clinically

Answer 53

- Petechiae - Bleeding: gums, melena, haematuria - Easy bruising

Question 54

Explain pathophysiology of ITP

Answer 54

IgG antibodies bind to glycoprotein IIa and IIb on platelets - which causes spleen to remove platelets

Question 55

What will be seen on FBC in ITP

Answer 55

Thrombocytopenia

Question 56

What will be seen on coagulation screen in ITP

Answer 56

Increased bleeding time

Question 57

What is used to control moderate bleeding in ITP

Answer 57

Tranexamic acid

Question 58

What is used to control severe bleeding in ITP

Answer 58

Glucocorticoids and IVIg