W24 - Paediatric hematology Flashcards
Name 4 things that could cause anaemia in a foetus/neonate
- TTTS
- Foetal-to-maternal transfusion
- Parvovirus infection (virus not cleared by immature immune cells)
- Haemorrhage from cord or placenta
if a lactating woman eats fava beans her G6PD-deficient baby boy may suffer _______
haemolysis
Name a blood pathology that is particularly common in Down Syndrome neonates.
Neonatal congenital leukaemia (also known as TAM: transient abnormal myelopoiesis)
Congenital leukaemia/TAM in trisomy 21:
- what lineage is usually involved?
- Relapse/remit pattern?
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
Newborn babies, in contrast to adults, have:
- A higher Hb
- A lower WBC
- Smaller red blood cells
- The same percentage of haemoglobin F
1.A higher Hb
Difference between thalassaemias and haemoglobinopathies
Thalassaemia - reduced synthesis of globin molecule
Haemoglobinopathies - synthesis of a structurally abnormal globin molecule
Haemoglobin A
Haemoglobin A2
Haemoglobin F
- describe globin chains of each
- describe period when mainly present
Haemoglobin A = a2B2 = late foetus, infant, child, adult
Haemoglobin A2 = a2delta2 = infant, child, adult
Haemoglobin F = a2gamma2 = foetus, infant
When does haemoglobin F levels begin to decline?
about 3 months of age
This is a blood film from someone with sickle cell anaemia - what do red and blue arrows show? What other pathology do you see?
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
Genotype of someone with sickle cell trait
Genotype of someone with sickle cell anaemia
Genotype of someone with sickle cell trait = B,B(s)
Genotype of someone with sickle cell anaemia = B(s), B(s)
Genotypes (2) of someone with heterozygous sickle cell disease
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
•Sickle cell anaemia is not clinically manifest at birth - why?
Clinical features become manifest as gamma chain production and haemoglobin F synthesis decrease and betaS and haemoglobin S production increase
Sickle cell anaemia is now usually diagnosed at ______ via ______
Sickle cell anaemia is now usually diagnosed at birth via heel prick test
What does this suggest in an young child?
Hand foot syndrome, also known as dactylitis - early complication of sickle cell disease, often seen at young age of 6 months to 2 years.
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?
The hand/foot syndrome
Vaso-occlusion in the 1st decade in sickle cell disease - describe when each is common:
- hand foot syndrome
- acute chest syndrome
- painful crises
- stroke
- 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
What is splenic sequestration? sequale of it?
Splenic sequestration is the acute pooling of a large % of circulating RBCs in the spleen = spleen acutely enlarges = Hb falls acutely, leading to:
- severe anaemia
- shock
- possible death
Splenic sequestration is more common in younger children - why?
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
What are the issues with having a small and fibrotic spleen in sickle cell disease?
Other than filtering and recylcing RBCs, the spleen is very important for filtering out bacteria and parasites
What is the issue with pneumococcus or parvovirus B19 in young children with sickle cell disease?
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
Why does folic acid matter more in a child with sickle cell disease than in a normal child or an adult? - give 3 reasons
- Hyperplastic erythropoiesis requires folic acid
- Growth spurts require folic acid
- Red cell life span is shorter so anaemia can rapidly worsen
Complications of sickle cell anaemia that are more common in adults than children include:
- Hand-foot syndrome
- Hyposplenism
- Red cell aplasia
- Splenic sequestration
- Stroke
- 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.
Siblings with sickle cell anaemia present simultaneously with severe anaemia and a low reticulocyte count—likely diagnosis?
- Splenic sequestration
- Parvovirus B19 infection
- Folic acid deficiency
- Haemolytic crisis
- Vitamin B12 deficiency
- Parvovirus B19 infection
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?
- Sickle cell trait
- Sickle cell anaemia
- Sickle cell/beta thalassaemia
2. Sickle cell anaemia
- dont get sickle cell blood cells in the peripheral blood
- MCV is normal, if it was a heterozygous state, there would be microcytosis
Beta thalassaemia is a condition resulting from reduced synthesis of beta globin chain and therefore ______________, and will likely manifest at ______ of age.
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.
Genotype of beta thalassaemia major
Genotype of beta thalassaemia trait
Genotype of beta thalassaemia major = B(thal), B(thal)
Genotype of beta thalassaemia trait = B(thal), B
Clinical effects of poorly treated thalassaemia major:
- anaemia =>
- erythropoietic drive =>
- iron overload =>
Clinical effects of poorly treated thalassaemia major:
- anaemia => HF, growth retardation
- erythropoietic drive => bone expansion, hepatomegaly, splenomegaly
- iron overload => HF, gonadal failure
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?
- Irregularly contracted cells (due to ROS damage)
- Bite cells (due to ROS damage)
- heinz bodies (dentured protein due to ROS dmage)
- Hb clustered to one side of cell (due to ROS damage)
likely G6PD deficiency
What are some 4 steps taken to treat infant/child with sickle cell disease
- Educate parents (acute spleen enlargment, pallor, SOB, etc)
- Vaccinate
- Folic acid
- Penicillin
What are some steps (3) to treat infant/child with beta thalassaemia major?
- Blood transfusions
- Monitoring for narrowing of cerebral vessels
- If iron overloaded => chelation therapy
What 4 advice do we give mother of child with G6PD deficiency?
be wary of:
- Infections
- Drugs
- Naphthalene
- Fava beans
The two important acquired haemolytic anaemias in children are…
- Autoimmune haemolytic anaemia (AIHA)
- Haemolytic uraemic syndrome (HUS)
Autoimmune haemolytic anaemia is characterized by:
______ in blood films
Positive result in ________ test
Autoimmune haemolytic anaemia is characterized by:
SPHEROCYTOSIS in blood films
Positive result in POSITIVE DIRECT ANTIGLOBULIN (COOMBS) test
4 presentation of haemophilia A and B in children
- Bleeding following circumcision
- Haemarthroses when starting to walk
- Bruises
- post-traumatic bleeding
3 presentations of von Willebrand disease in children
- Mucosal bleeding
- Bruises
- Post-traumatic bleeding
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?
- Haemophilia A
- Haemophilia B
- Von Willebrand disease
- Thrombotic thrombocytopenia purpura
- Has taken mother’s warfarin tablets
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.
Autoimmune thrombocytopenic purpura (‘ITP’) - 3 presentations in child
- Petechiae
- Bruises
- Blood blisters in mouth
Acute leukaemia in children is mainly _______, unless it’s below the age of 1 during which _______ is more common
Acute leukaemia in children is mainly ALL, unless it’s below the age of 1 during which AML is more common
