Haemolysis Flashcards
What is the definition of haemolysis?
Premature red cell destruction
What may be one of the first clinical signs suggestive that an individual is haemolysing?
Jaundice
What are the two main physiological responses to haemolysis?
Erythroid hyperplasia and reticulocytosis
Where are red blood cells broken down in extravascular haemolysis?
The reticuloendothelial system (predominantly liver and spleen)
Which is more common, intra or extravascular haemolysis?
Extravascular
Haemoglobinaemia and haemoglobinuria are only seen in which type of haemolysis: intra or extravascular?
Intravascular
Is haemosiderinuria seen in intravascular or extravascular haemolysis?
Intravascular
Which is the more common type of autoimmune haemolytic anaemia?
Warm haemolytic anaemia
Which is the more severe type of autoimmune haemolytic anaemia?
Cold haemolytic anaemia
What is the diagnostic test for autoimmune haemolytic anaemia?
Direct Coomb’s test
Which type of antibody is causative in warm autoimmune haemolytic anaemia?
IgG
Which type of antibody is causative in cold autoimmune haemolytic anaemia?
IgM
What is a potential underlying cause of both types of autoimmune haemolytic anaemia?
Lymphoproliferative disorders
Autoimmune disorders such as SLE may lead to the development of which type of autoimmune haemolytic anaemia?
Warm autoimmune haemolytic anaemia
Which drug class is recognised as a potential underlying cause for the development of warm haemolytic anaemia?
Penicillins
Infections such as EBV and mycoplasma are potential underlying causes for which type of autoimmune haemolytic anaemia?
Cold autoimmune haemolytic anaemia
What are the two main examples of alloimmune causes for haemolysis?
Haemolytic disease of the newborn and transfusion reactions
Which surgical procedure is a risk factor for the development of haemolytic anaemia?
Mechanical heart valve insertion
What infection may be responsible for causing acquired, non-immune haemolytic anaemia?
Malaria
What may be seen on a blood film of an individual with haemolysis as a consequence of severe burns?
Microspherocytes
Zieve’s syndrome is a triad of what 3 things?
Haemolysis, alcoholic liver disease and hyperlipidaemia
A deficiency in which vitamin may lead to red blood cell membrane defects and subsequent haemolysis?
Vitamin E
What are some examples of congenital conditions leading to haemolysis?
G6PD deficiency, hereditary spherocytosis, sickle cell anaemia
The presence of spherocytes on a peripheral blood film suggests there has been damage to which part of a red blood cell? What are some potential underlying causes for this?
Red blood cell membrane- caused by hereditary spherocytosis or autoimmune haemolytic anaemia
The presence of red cell fragments on a peripheral blood film is suggestive of what?
Mechanical damage
The presence of Heinz bodies on a peripheral blood film is suggestive of what?
G6PD deficiency
In warm autoimmune haemolytic anaemia, is the haemolysis intra or extravascular?
Extravascular
In cold autoimmune haemolytic anaemia, is the haemolysis intra or extravascular?
Intravascular
What happens to serum LDH in haemolytic anaemia?
Increased serum LDH
The presence of schistocytes on a peripheral blood film is suggestive of what cause for haemolytic anaemia?
Microangiopathic haemolytic anaemia (i.e. HUS, TTP, DIC etc)
Where does the haemolysis take place in hereditary spherocytosis?
Spleen
An aplastic crisis occurs when individuals with G6PD deficiency become infected with what organism?
Parvovirus B19
What treatment is required for all patients with hereditary spherocytosis?
Folic acid supplements
What definitive treatment may be offered to individuals with severe hereditary spherocytosis?
Splenectomy
What measures are taken to address the increased infection risk following a splenectomy?
Pneumococcal vaccination and long-term prophylactic penicillin
How is hereditary spherocytosis inherited?
Autosomal dominant
How is G6PD deficiency inherited?
X-linked recessive
Intake of what food can precipitate acute intravascular haemolysis in those with G6PD deficiency?
Broad beans
Does G6PD deficiency normally require any long-term treatment?
No
