3: Haemolytic Anaemia Flashcards
What is haemolytic anaemia
pre-mature destruction of RBC
What is the lifespan of a RBC
120-days
What are the two types of haemolytic anaemia
Intravascular haemolysis
Extravascular haemolysis
Where does intravascular haemolysis occur
Inside blood-vessels
Where does extravascular haemolysis occur
Outside blood-vessels
Aside from intravascular-extravascular how can anaemia be divided
Hereditary
Acquired
What are the 2 hereditary haemolytic anaemia due to enzyme defects
- G6PD Deficiency
- Pyruvate Kinase Deficiency
What are the 2 hereditary haemolytic anaemia due to membrane defects
- Hereditary spherocytosis
- Hereditary elliptocytosis
What are the 2 haemolytic anaemia due to haemaglobinopathies
- Thalasemia
- Sickle cell
How can acquired haemolytic anaemias be divided
Immune mediated and non-immune mediated
If an immune mediated haemolytic anaemia, what will be positive
Coombs test (Direct antibody test)
what is a group of Coombs negative acquired haemolytic anaemia
Microangiopathic haemolytic anaemia
What is the inheritance pattern of G6PD deficiency
X-Linked recessive
How does G6PD present normally
Asymptomatic
What can precipitate a crisis in G6PD deficiency
- anti-malarial
- sulphur containing drugs: sulphonylurea, sulphasalazine,
- ciprofloxacin
- fava beans
How will G6PD crisis present
Jaundice
Gall stones
Splenomegaly
How may G6PD manifest in early days of life
Neonatal Jaundice
what is the most common RBC enzyme defect
G6PD Deficiency
which gender is G6PD more common in and why
Males - due to x-linked recessive
explain pathophysiology of G6PD
G6PD reduces glutathione. Deficiency therefore increases glutathione and oxidative stress leading to RBC breakdown and intravascular haemolysis
what will be seen on a blood film in G6PD
- Heinz bodies
- Bite cells
- Blister cells
explain management G6PD
- avoid precipitants such as henna
- transfuse if severe
what is the inheritance pattern of pyruvate kinase deficiency
Autosomal recessive
how will patients with pyruvate kinase deficiency present
symptomatic:
- Jaundice
- Lethargy
- Splenomegaly
- Pruritus
what is hereditary spherocytosis
autosomal dominant condition affecting RBC cytoskeleton causing it to form a spherical, opposed to bi con-cave, shape
how does hereditary spherocytosis present clinically
- Jaundice
- Pigment gallstones
- Splenomegaly
- Aplastic crisis due to parvovirus B19
if equivocal about diagnosis of HS, how is patient investigated
cryohaemolysis test and EMA binding
how is HS managed
- Folate
- Splenectomy
how does hereditary elliptocytosis present
Autosomal dominant condition where there is defect in RBC causing it to form a spherical shape
what is the advantage of hereditary elliptocytosis
Protective against malaria
what are autoimmune haemolytic anaemia
Extravascular haemolysis mediated by auto-antibody binding
what are autoimmune haemolytic anaemias characterised by
Temperature at which autoantibodies bind
what are the 3 types of AIHA
- Warm AIHA
- Cold AIHA
- Paroxysmal Cold Haemaglobinuria
what antibody mediates warm AIHA and how can you remember this
IgG
Grace is a warm person
what temperature do antibodies bind in warm AIHA
37’
what type of haemolysis does warm AIHA lead to
Extravascular
what will be seen on peripheral blood smear in warm AIHA
Spherocytes
what test will be positive in warm AIHA
Coombs test
Direct antiglobulin test
overall what can be given to control symptoms of warm AIHA
glucocorticoids
how is warm AIHA managed in adults
splenectomy
how is warm AIHA managed in children
rituximab
what antibody mediates cold AIHA
IgM
what temperature does IgM bind RBC in cold AIHA
Below 4’
explain presentation of cold AIHA
Chronic anaemia worsened by the cold
what test is positive in cold AIHA
Coombs test (Dat test)
how is cold AIHA managed
- Keep warm
- Chlorambucil
what is paroxysmal cold haemaglobinuria
mediated by the donath Landsteiner antibody that binds RBC in the cold and then causes haemolysis on re-warming
what antibody causes paroxysmal cold haemaglobinuria
donath landsteiner
what is the stereotype for paroxysmal cold haemaglobinuria
young child playing in the cold then comes inside and is jaundiced and fatigued
what is paroxysmal nocturnal haemaglobinuria
rare disorder where there is haemolysis at night leading to marrow failure
what is indicative of PNH
urinary haemosiderin
