Haemolysis Flashcards
Classification of haemolysis by site
Extravascular
Intravascular
Test results indicative of haemolysis (6)
Low Hb Unconjugated hyperbilirubinaemia Increased serum LDH Reticulocytosis Spherocytes (extravascular) Schistocytes (intravascular)
Reasons why spleen may be enlarged in haemolysis (2)
Volume of red cells being phagocytosed in spleen
Extramedullary haemopoiesis
Parvovirus infection in haemolytic patients can lead to…
Red cell aplasia
Hereditary spherocytosis (HS) results from…
mutations in genes linking the red cell membrane to the cytoskeleton
Inheritance of HS
Usually autosomal dominant
Complications of chronic haemolysis in HS (3)
Gallstones/biliary obstruction
Aplastic crises
Megaloblastic anaemia due to folate deficiency (3)
Diagnostic test for HS
Osmotic fragility test (RBCs show increased fragility in hypotonic solution)
Management of HS (2)
Folate replacement
Splenectomy
Genetic cause of G6PD deficiency
X-linked recessive mutations in G6PD
How does G6PD deficiency cause haemolysis?
Makes the red cells vulnerable to oxidative stress
Blood film results in G6PD deficiency (2)
Heinz bodies- red cell inclusions due to haemoglobin denaturation
“Bite cells”
Precipitants of crisis in G6PD deficiency (4)
Broad beans (favism)
Infections
Antimalarials
“Sulfa” drugs
Diagnostic test for G6PD
G6PD enzyme assay
Management of G6PD
Avoidance of precipitants
Inherited causes of haemolysis (3)
Hereditary spherocytosis
Sickle cell anaemia
G6PD deficiency
Classification of acquired haemolysis
Immune and non-immune
Types of autoimmune haemolytic anaemias (3)
Warm-reactive
Cold-reactive
Paroxysmal
Which type of autoimmune haemolytic anaemia responds to changes in ambient temperature?
Cold-reactive
Diagnostic test for autoimmune haemolytic anaemias
Direct antiglobulin test (Coomb’s test)
Describe how Coomb’s test works
Blood sample from patient with antibodies attached to red cells is incubated with anti-Ig antibodies- causes agglutination
Examples of situations where alloimmune haemolytic anaemia might arise (2)
Acute transfusion reaction
Haemolytic disease of the newborn
Causes of non-immune acquired haemolytic anaemia (5)
MAHA (causes include HUS, DIC) Burns Infections e.g. malaria Hypersplenism Drugs/chemicals e.g. lead, copper
