Haemolytic anaemias Flashcards
Warm Antibody autoimmune haemolytic anaemia
IgG (type 2) mediated at 37 degrees (body temp)
causing haemolysis and shperocytosis
Cold Antibody AIHA
IgM (type 2 ) mediated at 4-23 degrees (cold to room temp)
Ix for AIHA
Direct Coombs test
+ve = Warm Antibody IgG
+ve for compliment Only = Cold antibody IgM
Cause of Warm Ab AIHA
Auto-immune, Drugs, CLL
Causes of Cold ab AIHA
Auto-immune, Infection, Lymphoma
Further investigations (you may wish to do these)
FBC, Retic count, Blood film (spherocytosis)
Serum Billi and LDH
NOTE: the coombs test will Direct you management plan
Mx of Cold AIHA
Avoid the cold/Keep warm
Rituximab
Mx of Warm AHIA
Steroids/Immunosupression
+/- splenectomy
Hereditary Spherocytosis
Autosomal Dominant defect in RBC membrane
Spherocytes get trapped in the spleen –> extracellular haemolysis
Features of Spherocytosis
Splenomegaly
Pigmented gallstones
jaundice
Ix of spherocytosis
Blood film shows spherocytes (same as warm AIHA BUT…)
Coombs test -ve
Mx of Spherocytosis
Folate and Splenectomy (after childhood)
G6DP deficiency
X-linked results in RBC oxidative damage
Triggers
Broad beans
Naphthaline (moth balls)
Infection
Drugs: antimalarials
Ix of G6PD deficiency
Film: irregular contracted cells/bite cells and heinz bodies
G6DP assay after 8wks - reticulocytes have high G6PD
Rx of G6PD
Treat underlying cause/Remove precipitant
Transfusion may be required
Pyruvate Kinase Deficiency
Autosomal recessive defect in ATP synthesis
Features of pyruvate kinase deficiency
Rigid cells phagocytosed in the spleen
Splenomegaly
Anaemia + jaundice
IX of PK deficiency
PK enzyme assay
Rx of PK deficiency
Transfusion +/- splenectomy
Pathogenesis of Sickle cell anaemia
Point mutations of B-globin
SCA = HbSS
Trait = HbAS
HbS insoluble when deoxygenated –> sickling
Sickle cells have a shorter lifespan –> haemolysis (intravascular)
Sickle cells get trapped in microvascualture –> thrombosis
Ix of SS
Blood film - sickle cells and target cells
Hb electrophoresis - can be done at birth w/ neonatal screening
Presentation of sickle cell
SICKLED
S - Splenomegaly I - Infarction C - Crisis K - Kidney Disease L - Liver/Lung E - Erectile Dysfunction D - Dactylis
Mx of Sickle cell
CHRONIC DISEASE
Pen + immunisations
Hydroxycarbamide if frequent crisis (revery HbA to HbF which has greater affinity for O2)
ACUTE CRISIS IV opioids - give within 30 minutes it hurts like hell Hydration + O2 Tx precipitating infection Fluids if its in the chest Resp support Blind Abx - Ceftriaxone
Transfuse if severe
