Haemolytic anaemia Flashcards
What are the causes of intravascular haemolysis?
Mismatched blood transfusion
G6PD deficiency
Paroxysmal nocturnal haemoglobinuria
Cold autoimmune haemolytic anaemia
Red cell fragmentation
- TTP
- DIC
- HUS
- mechanical heart valves
What causes extravascular haemolysis?
Haemoglobinopathies
- sickle cell
- thalassaemia
Hereditary spherocytosis
Haemolytic disease of newborn
Warm autoimmune haemolytic anaemia
What would be a classic presentation of intravascular haemolysis?
Systemic shock - fever, tachycardia, hypotension, AKI
Schistocytes on blood film
Raised LDH +++
What would be a classic presentation of extravascular haemolysis?
Less severe symptomatically
Splenomegaly/hepatomegaly
What is the most common type of autoimmune haemolytic anaemia?
Warm haemolytic anaemia
What are the causes of warm AIHA?
Idiopathic
Autoimmune disease - eg lupus
Neoplasm - CLL, lymphoma
Drugs - eg methyldopa
What is the management of warm AIHA?
Steroids +/- Rite
Management of underlying condition
What antibody mediates warm AIHA?
IgG
What antibody mediates cold AIHA?
IgM
What type of haemolysis does warm AIHA cause?
Extravascualr haemolysis
What type of haemolysis does cold AIHA cause?
Intravascualr haemolysis
What are the common causes of cold AIHA?
Neoplasm - lymphoma
Infection - EBV, mycoplasma
What is the classic presentation of cold AIHA?
Raynaud’s
Acrocyanosis (blue discolouration peripheries)
What is MAHA?
Microangiopathic haemolytic anaemia
What is microangiopathic haemolytic anaemia?
Subgroup of haemolytic anaemias where haemolysis occurs in small blood vessels
What are the common causes of MAHA?
DIC
HUS
TTP
HELLP
Cancer
Drugs - rifampicin
What is paroxysmal nocturnal haemoglobinuria?
Acquired disorder leading to intravascular haemolysis
What are the features of paroxysmal nocturnal haemoglobinuria?
Haemolytic anaemia
Dark coloured urine, esp in morning
Thrombosis
Can cause pancytopenia
How is paroxysmal nocturnal haemoglobinuria diagnosed?
Flow cytometry of blood - low CD59 and CD55
What is the management of paroxysmal nocturnal haemoglobinuria?
Anticoagulation
Transfusion support
Stem cell transplant
Monoclonal antibodies against C5 show promise