Haematology Flashcards
What is beta trait?
High HbA2, HbF
What is alpha trait?
Low/normal HbA2, HbF
What is the HbA2 like in beta trait?
High
What is the HbF trait like in alpha trait?
Low
What are the thalassemias?
A group of heritable hypochromic anaemias
Beta thalassemia is the commonest
1 in 7 Cypriots, 1 in 10 Indians
Overall 3% of world population
What is the epidemiology of beta thalassemia?
1 in 7 Cypriots, 1 in 10 Indians
Overall 3% of world population
What is beta thalassemia?
High HbA2
Heterozygous, hypochromic, microcytic anaemia
Diagnose using haemaglobin electrophoresis
What are the types of thalassemia?
What are the features of thalassemia major?
How is assymptomatic thalassemia treated?
Asymptomatic carriers: require no specific treatment but should be protected from detrimental iron supplementation, which should only be given after confirmation of iron deficiency.
How is thalasemmia major treated?
What is a drawback of excessive milk intake?
Reduced iron intake
How is sickle cell anaemia treated?
IF U HARP
Immunisations
Fluids
Urea/ hydroxyurea or carbamide
Hydration
Antibiotics
Raised temperature
Pain relief
What is the mechanism behind ITP?
Antibodies directed against viral antigens during a viral illness may cross-react with normal platelet antigens (molecular mimicry)
How does ITP present on a FBC?
Platelets
An isolated thrombocytopenia with a platelet count of <100x109/L is usually the only blood abnormality
According to UptoDate, most presenting cases have a count of <30x109/L because those with a higher count tend to be asymptomatic and therefore do not get investigated
White blood cells
Should be within normal limits
If abnormal, should spark suspicion of another condition (see below)
Haemoglobin
Usually within normal limits
Anaemia is very occasionally seen, usually in children who have had significant haemorrhage
How does ITP petechiae present?
How is ITP assessed?
What medications are avoided in ITP?
Medicines such as Ibuprofen and
aspirin should be avoided as they stop the platelets working effectively
How can platelet numbers be improved in ITP?
How is moderate to severe ITP treated?
In general, if treatment is required, a platelet target of ≥20,000 to 30,000/microL is used (the platelet count threshold above which the risk of serious bleeding is reduced)
Corticosteroids
According to BMJ best practice, this is the usual first-line treatment
Prednisolone 1-2mg/kg/day orally, with tapering as soon as symptoms begin to clear
IVIg and anti-D immunoglobulin
Reserved for if corticosteroids are contraindicated or ineffective
In those who are resistant to the above treatment, or in those with chronic ITP, medications such as mycophenolate, rituximab and thrombopoietin receptor agonists can be considered (with specialist input)
How is lifethreatening ITP managed?
In those with severe haemorrhage, aggressive treatment is required
According to BMJ best practice, the first line management is with IVIg, corticosteroids, plus platelet transfusions
IVIg 1g/kg intravenously as a single dose
Prednisolone 1-2mg/kg/day orally
Alternatively, UptoDate suggest methylprednisolone 30 mg/kg per day (up to 1 g) intravenously for 3-4 days
Platelet transfusions
UptoDate recommend platelet transfusions of a bolus dose of 10-30 mL/kg, then followed by a continuous infusion
The role of these platelet transfusions is to ensure that the child maintains a haemostatic platelet count and to guide further treatment
Therefore, platelet transfusions are not curative in nature, as the platelets will continue to be destroyed at a more rapid rate due to the auto-immune processes in ITP
If severe haemorrhage results in hypovolaemia, fluid resuscitation is also indicated, however this is extremely rare
What is the most common childhood malignancy?
Leukemia makes up 35% of all childhood malignancies
80% are ALL
How does ALL present?
Malaise
Anaemia
Bruising
Bone pain
Lymphadenopathy
What is ALL?
Peaks at age 2-5
Prognosis is worse for those presenting under 2 or over 10
Insidious onset
Anaemia, thrombocytopenia and raised leukocytes
Blast cells are seen on a blood film
Bone marrow aspirate taken
TEL-AML1 fusion gene in 20% of cases
How is ALL treated?
What are the complications of ALL?
Tumour lysis syndrome
Neutropenic sepsis
Mucositis
What is haemolytic disease of the newborn?
When maternal IgG crosses across the placenta and reacts with fetal red blood cells. Rhesus negative women should be given anti-D antibody at 28 weeks.
Management can be phototherapy and exchange
What are two complications of haemolytic disease of the newborn?
Kernicterus
Hydrops fetalis (oedema)
How does phototherapy work for haemolytic disease of the newborn?
450nm wavelength helps convert unconjugated bilirubin to bilverdin
