W24 - Paediatric hematology

Question 1

Name 4 things that could cause anaemia in a foetus/neonate

Answer 1

1. TTTS
2. Foetal-to-maternal transfusion
3. Parvovirus infection (virus not cleared by immature immune cells)
4. Haemorrhage from cord or placenta

Question 2

if a lactating woman eats fava beans her G6PD-deficient baby boy may suffer _______

Answer 2

haemolysis

Question 3

Name a blood pathology that is particularly common in Down Syndrome neonates.

Answer 3

Neonatal congenital leukaemia (also known as TAM: transient abnormal myelopoiesis)

Question 4

Congenital leukaemia/TAM in trisomy 21:

• what lineage is usually involved?
• Relapse/remit pattern?

Answer 4

Congenital leukaemia/TAM:

• what lineage is usually involved = myeloid with major involvement of megakaryocyte lineage
• Relapse/remit pattern = remits spontaneously, 1/4th relapse in 1-2 years

Question 5

Newborn babies, in contrast to adults, have:

1. A higher Hb
2. A lower WBC
3. Smaller red blood cells
4. The same percentage of haemoglobin F

Answer 5

1.A higher Hb

Question 6

Difference between thalassaemias and haemoglobinopathies

Answer 6

Thalassaemia - reduced synthesis of globin molecule

Haemoglobinopathies - synthesis of a structurally abnormal globin molecule

Question 7

Haemoglobin A

Haemoglobin A2

Haemoglobin F

• describe globin chains of each
• describe period when mainly present

Answer 7

Haemoglobin A = a2B2 = late foetus, infant, child, adult

Haemoglobin A2 = a2delta2 = infant, child, adult

Haemoglobin F = a2gamma2 = foetus, infant

Question 8

When does haemoglobin F levels begin to decline?

Answer 8

about 3 months of age

Question 9

This is a blood film from someone with sickle cell anaemia - what do red and blue arrows show? What other pathology do you see?

Answer 9

Red = sickle cell

Blue = cell with underlying polymerisation of Hb = will transofrm to sickled cells

Howell jolly bodies = remnant nuclei in RBCs = should be removed by spleen = seen in functional asplenia (sickle cell) or those with splenectomy

Question 11

Genotype of someone with sickle cell trait

Genotype of someone with sickle cell anaemia

Answer 11

Genotype of someone with sickle cell trait = B,B(s)

Genotype of someone with sickle cell anaemia = B(s), B(s)

Question 12

Genotypes (2) of someone with heterozygous sickle cell disease

Answer 12

Genotypes (2) of someone with heterozygous sickle cell disease =

1. B(s), B(c) = sickle cell/haemoglobin C disease

2. B(s), B(thal) = sickle cell/beta thalassaemia

Question 13

•Sickle cell anaemia is not clinically manifest at birth - why?

Answer 13

Clinical features become manifest as gamma chain production and haemoglobin F synthesis decrease and betaS and haemoglobin S production increase

Question 14

Sickle cell anaemia is now usually diagnosed at ______ via ______

Answer 14

Sickle cell anaemia is now usually diagnosed at birth via heel prick test

Question 15

What does this suggest in an young child?

Answer 15

Hand foot syndrome, also known as dactylitis - early complication of sickle cell disease, often seen at young age of 6 months to 2 years.

Question 16

The distribution of red bone marrow (susceptible to infarction) differs between infant/child with sickle cell anaemia vs an adult - what does this lead to?

Answer 16

The hand/foot syndrome

Question 18

Vaso-occlusion in the 1st decade in sickle cell disease - describe when each is common:

• hand foot syndrome
• acute chest syndrome
• painful crises
• stroke

Answer 18

• hand foot syndrome = 6 months -> 2 years
• acute chest syndrome = 6 months -> 10 years
• painful crises = 6 months -> 10 years
• stroke = 1 year -> 10 years

Question 19

What is splenic sequestration? sequale of it?

Answer 19

Splenic sequestration is the acute pooling of a large % of circulating RBCs in the spleen = spleen acutely enlarges = Hb falls acutely, leading to:

1. severe anaemia
2. shock
3. possible death

Question 20

Splenic sequestration is more common in younger children - why?

Answer 20

Splenic sequestration happens in younger children because the infant still has a functioning spleen. It doesn’t happen in older children and adults because recurrent infarction has left the spleen small and fibrotic

Question 21

What are the issues with having a small and fibrotic spleen in sickle cell disease?

Answer 21

Other than filtering and recylcing RBCs, the spleen is very important for filtering out bacteria and parasites

Question 22

What is the issue with pneumococcus or parvovirus B19 in young children with sickle cell disease?

Answer 22

Infants and children with sickle cell disease initially have an immature immune system and no immunity to microbes such as parvovirus B19—their first exposure leads to pure red cell aplasia

Question 23

Why does folic acid matter more in a child with sickle cell disease than in a normal child or an adult? - give 3 reasons

Answer 23

1. Hyperplastic erythropoiesis requires folic acid
2. Growth spurts require folic acid
3. Red cell life span is shorter so anaemia can rapidly worsen

Question 24

Complications of sickle cell anaemia that are more common in adults than children include:

1. Hand-foot syndrome
2. Hyposplenism
3. Red cell aplasia
4. Splenic sequestration
5. Stroke

Answer 24

2. Hyposplenism

Stroke is interesting – stroke is common in middle age and elderly, but in sickle cell anaemia it’s a condition of children and likely due to blood vessels in brain of children being narrower.

Question 25

Siblings with sickle cell anaemia present simultaneously with severe anaemia and a low reticulocyte count—likely diagnosis?

1. Splenic sequestration
2. Parvovirus B19 infection
3. Folic acid deficiency
4. Haemolytic crisis
5. Vitamin B12 deficiency

Answer 25

2. Parvovirus B19 infection

Question 26

A 6-year-old Afro-Caribbean boy presents with chest and abdominal pain; Hb is 63 g/l, MCV 85 fl and blood film shows sickle cells—likely diagnosis?

1. Sickle cell trait
2. Sickle cell anaemia
3. Sickle cell/beta thalassaemia

Answer 26

2. Sickle cell anaemia

1. dont get sickle cell blood cells in the peripheral blood
2. MCV is normal, if it was a heterozygous state, there would be microcytosis

Question 27

Beta thalassaemia is a condition resulting from reduced synthesis of beta globin chain and therefore \_\_\_\_\_\_\_\_\_\_\_\_\_\_, and will likely manifest at ______ of age.

Answer 27

Beta thalassaemia is a condition resulting from reduced synthesis of beta globin chain and therefore **_haemoglobin A,_** and will likely manifest at **_3-6 months_** of age.

Question 28

Genotype of beta thalassaemia major Genotype of beta thalassaemia trait

Answer 28

Genotype of beta thalassaemia major = **B(thal), B(thal)** Genotype of beta thalassaemia trait = **B(thal), B**

Question 29

Clinical effects of poorly treated thalassaemia major: - anaemia =\> - erythropoietic drive =\> - iron overload =\>

Answer 29

Clinical effects of poorly treated thalassaemia major: - anaemia =\> **HF, growth retardation** - erythropoietic drive =\> **bone expansion, hepatomegaly, splenomegaly** - iron overload =\> **HF, gonadal failure**

Question 30

7-year-old Afro-Caribbean boy had abdominal pain and urinary tract symptoms and was given an anti-emetic by his G.P. 3 days later he was noted to have yellow eyes and was brought to the hospital WBC 10.9 × 109/l, Hb 58 g/l, MCV 100 fl, platelet count 275 × 109/l These are his blood films. What do you see? Diagnosis?

Answer 30

1. Irregularly contracted cells (due to ROS damage) 2. Bite cells (due to ROS damage) 3. heinz bodies (dentured protein due to ROS dmage) 4. Hb clustered to one side of cell (due to ROS damage) likely G6PD deficiency

Question 31

What are some 4 steps taken to treat infant/child with sickle cell disease

Answer 31

1. Educate parents (acute spleen enlargment, pallor, SOB, etc) 2. Vaccinate 3. Folic acid 4. Penicillin

Question 32

What are some steps (3) to treat infant/child with beta thalassaemia major?

Answer 32

1. Blood transfusions 2. Monitoring for narrowing of cerebral vessels 3. If iron overloaded =\> chelation therapy

Question 34

What 4 advice do we give mother of child with G6PD deficiency?

Answer 34

be wary of: * Infections * Drugs * Naphthalene * Fava beans

Question 35

The two important acquired haemolytic anaemias in children are...

Answer 35

1. Autoimmune haemolytic anaemia (AIHA) 2. Haemolytic uraemic syndrome (HUS)

Question 36

Autoimmune haemolytic anaemia is characterized by: \_\_\_\_\_\_ in blood films Positive result in ________ test

Answer 36

Autoimmune haemolytic anaemia is characterized by: **_SPHEROCYTOSIS_** in blood films Positive result in **_POSITIVE DIRECT ANTIGLOBULIN (COOMBS)_** test

Question 37

4 presentation of haemophilia A and B in children

Answer 37

1. Bleeding following circumcision 2. Haemarthroses when starting to walk 3. Bruises 4. post-traumatic bleeding

Question 38

3 presentations of von Willebrand disease in children

Answer 38

1. Mucosal bleeding 2. Bruises 3. Post-traumatic bleeding

Question 39

A 1-year-old boy presents with joint bleeding, Hb, WBC and platelet count are normal, aPTT is prolonged, PT is normal, bleeding time normal—most likely diagnosis? 1. Haemophilia A 2. Haemophilia B 3. Von Willebrand disease 4. Thrombotic thrombocytopenia purpura 5. Has taken mother’s warfarin tablets

Answer 39

1.Haemophilia A long aPTT suggests it's either 1, 2, or 3. Nomral PT suggests it's not VWD. H.A is more common than H.B so answer is 1.

Question 40

Autoimmune thrombocytopenic purpura (‘ITP’) - 3 presentations in child

Answer 40

1. Petechiae 2. Bruises 3. Blood blisters in mouth

Question 41

Acute leukaemia in children is mainly \_\_\_\_\_\_\_, unless it's below the age of 1 during which _______ is more common

Answer 41

Acute leukaemia in children is mainly **_ALL_**, unless it's below the age of 1 during which **_AML_** is more common