7: Haemolysis Flashcards
What are the products of red blood cell breakdown?
Iron
Bilirubin
Amino acids
How long does a red blood cell normally last in the circulation?
120 days
What is haemolysis?
Premature RBC destruction
What shape are red blood cells?
Biconcave
Greater surface area, allows them to squeeze through bone marrow and high pressure circulation
Which organelles do red blood cells lack?
Nucleus
Mitochondria
What process compensates for haemolysis?
Erythropoiesis
i.e RBC production
In compensated haemolysis, ___ concentration is maintained within normal limits.
Hb
In ___ haemolysis, Hb concentration decreases.
decompensated haemolysis
What change occurs in the bone marrow secondary to haemolysis?
Hyperplasia
What clinical sign can be seen in patients with haemolysis?
Jaundice
Increased levels of bilirubin
Which kind of cells are seen in increased numbers in the bone marrow in response to anaemia?
Reticulocytes
Reticulocytosis
Why do reticulocytes stain blue-grey (polychromatic) on a blood film?
They still have RNA
Producing cells of different colours, i.e a polychromasia
Is reticulocytosis only seen in haemolytic anaemia?
No
Bone marrow response to anaemia - bleeding, iron deficiency etc.
How are reticulocytes described when stained on a blood film?
Polychromatic
What is erythroid hyperplasia?
Increase in bone marrow cell number in response to EPO
In which organs can red blood cells be broken down?
Spleen
Liver
Apart from the spleen and liver, where can red blood cells be broken down?
Circulation
(Intravascular / Extravascular) haemolysis is more common.
Extravascular haemolysis more common
What happens to the organs in which haemolysis occurs?
Increase in size
so producing splenomegaly, hepatomegaly
What are the RBC products released in extravascular haemolysis?
Normal products
i.e bilirubin, iron and amino acids
Intravascular haemolysis is a (normal / abnormal) process.
abnormal
so the products released are abnormal as well and you get symptoms like pink urine
Patients given which type of blood transfusion can develop haemolysis?
Incorrect group
Which enzyme deficiency, increasing oxidative stress exerted on red blood cells, can cause haemolytic anaemia?
G6PD deficiency
Which infection can cause haemolytic anaemia?
Malaria
What are the two types of haemolytic anaemia?
Intravascular
Extravascular
What is the most common inherited disorder causing haemolytic anaemia in the UK?
Hereditary spherocytosis
Haemolytic anaemia is commonly caused by ___ disease.
autoimmune disease
Which connective tissue disease can cause autoimmune haemolysis?
SLE
Autoimmune haemolysis is caused by either ___ or ___ autoantibodies.
warm or cold
What type of antibody are warm AH antibodies?
IgG
more common than cold
Which test is used to diagnose warm autoimmune haemolysis?
Coombs test
Should be +ve
What type of hypersensitivity reaction is a blood transfusion reaction?
Type II
Antibody-mediated
What causes most haemolytic disease in newborns?
Rhesus reaction
RhD- mother receives RhD+ blood from baby (haemorrhage, birth etc.), autoantibody response which then goes back to baby causing haemolysis
Avoid with anti-D injections
Which specific GI infection may cause acquired haemolytic anaemia?
E. coli 0157
Why can implanted heart valves cause haemolysis?
Mechanical damage to RBCs
i.e cells bouncing off metal
Problems with which part of a red blood cell can cause haemolysis?
Cell membrane
What is the most common inherited condition causing haemolytic anaemia?
What cell structure does it affect?
Hereditary spherocytosis
Cell membrane
Which molecule keeps iron in its ferrous (Fe2+) form in red blood cells?
NADPH
Which cause of increased oxidative stress can cause haemolysis?
G6PD deficiency
Which derm condition is associated with Coeliac disease?
Dermatitis herpetiformis
Which treatment for dermatitis herpetiformis is associated with haemolysis?
Oral dapsone
Which disease affecting the structure of haemoglobin can cause haemolysis?
Sickle cell disease
What haematological disorder is frontal bossing associated with?
Beta thalassaemia
Blood transfusion reactions are a cause of (extravascular / intravascular) haemolysis.
intravascular
What are the signs and symptoms of hereditary spherocytosis?
Intermittent jaundice
Gallstones
Splenomegaly > Splenectomy at young age
Malaria causes (extravascular / intravascular) haemolysis.
intravascular haemolysis
What is HbH disease?
What is HbH?
Form of alpha thalassaemia (3 out of 4 genes deleted)
Crap form of Hb with 4 beta chains
Flare ups with stress, drugs
What is the definition of haemolysis?
PREMATURE RED CELL DESTRUCTION
