Haemolytic Anaemias Flashcards
What is haemolytic anaemia?
Increased peripheral destruction of RBCs
- Shortened RBC life span (normally 120 days)
Bone marrow continues to produce cells
- Pathology is in the red cell itself, or its environment
Increased consumption means BM has to work harder to compensate
- As the BM tries to keep up, the patient becomes anaemic - RBC destroyed > RBC produced
What are the different categories of homeless?
- Inherited - Present form birth
- Immune - Antibody mediated
- Extravascular - Site of destruction is the spleen and other RES organs
- Acquired - Develops de novo - ?why
- Non-immune - RBC or environment
- Intravascular - Site of destruction is within the vascular space.
What are the inherited problems of RBCs and what type of haemolysis is it?
- Sickle cell disease - Extravascular & intravascular haemolysis
- Membrane disorders e.g. hereditary spherocytosis - Extravascular
- G6PD deficiency - intravacular
What are the acquired problems with RBCs and what type of haemolysis is it?
Paroxysmal nocturnal haemoglobinuria (PNH) - intravascular
What are the acquired problems with the RBC environment and what type of haemolysis is it?
- Microangiopathic haemolysis (MAHA): TTP, DIC, HELLP - intravascular
- Valve haemolysis - intravascular
What are the acquired Ab-mediated attacks on RBC s and what type of homeless is it?
- Autoimmune: warm, cold, drug induced - intravascular and extravascular
- Alloimmune - transfusion reaction, HDFN - intravascular
What is investigated and seen on a homeless screen?
- FBC - Normocytic anaemia
- Blood film - Spherocytes or red cell fragments
- Reticulocytes - Increased
- LDH - Increased (due to cell turnover)
- Bilirubin - Increased (unconjugated)
- Haptoglobin - Decreased in intravascular haemolysis
- DAT - Positive in some immune cases
What is seen in intravascular haemolysis/
- Increased: unconjugated bilirubin, LDH, reticulocytes
- Decreased haptoglobin
- Haemoglobinuria, haemoglobinaemia,
