HA Flashcards
What is anaemia?
→reduced haemoglobin level for the age and gender of the individual
What is haemolytic anaemia?
→anaemia due to shortened RBC survival
What is the difference in Hb between neonates and infants?
→Hb is higher than in infants
How long do RBCs go without nuclei or cytoplasmic cells?
→120 days
What is the width of capillaries?
→3.5 microns
How are senescent RBCs removed?
→RES by the liver and spleen
Describe haemolysis
→Shortened red cell survival 30-80 days
→Compensation by Bone marrow to increase production
→Increased young cells in circulation = Reticulocytosis +/- nucleated RBC
→RBC production unable
to keep up with decreased RBC life span
→Decreased Hb
What is incomplete compensated haemolysis?
→RBC production unable
to keep up with decreased RBC life span
Why does reticulocytosis occur?
→due to reduced Hb
→the bone marrow may increase its output of red cells
→expanding the volume of active marrow
What are the clinical findings of haemolytic anaemia?
→Jaundice- increase in unconjugated bilirubin
→Pallor
→Fatigue
→Splenomegaly
What are the chronic clinical findings of haemolytic anaemia?
→Gallstones - pigment
→Leg ulcers- local ischemia
→Folate deficiency - (increased use)
What are the lab investigations for HA?
→Peripheral blood film
What are features of the lab investigations for HA?
→polychromatophilia(much bigger),
→nucleated rbc,
→ thrombocytosis;
→neutrophilia with left shift
What do morphological clues of HA lead to?
→underlying disorder
What are some morphological abnormalities of HA?
→Spherocytes,
→Sickle cell, Target cells,
→Schistocytes (fragmented, triangular rbc)
→acanthocytes
What are the bone marrow findings of HA?
→Erythroid hyperplasia of BM
→normoblastic reaction
→Reversal of Myeloid: Erythroid ratio
→Reticulocytosis
What are other findings of HA?
→Increased unconjugated bilirubin →Increased LDH (lactate dehydrogenase) →Decreased serum haptoglobin protein that binds free Hb →Increased urobilinogen →Increased urinary hemosiderin
What is hemosidirin?
→brown iron-containing pigment usually derived from the disintegration of extravasated red blood cells
What are the different classifications of haemolytic anaemias?
→Inheritance
→Site of RBC destruction
→Origin of RBC damage
What are the inheritance classification of HA?
→hereditary eg Hereditary spherocytosis
→acquired eg Paroxysmal nocturnal haemoglobinuria, IHA
What are classifications of sites of RBC production in HA?
→intravascular eg Thrombotic thrombocytopenic purpura, haemolytic transfusion
→ extravascular eg Autoimmune haemolysis
What are the classifications of origin of RBC damage in HA?
→Intrinsic (Intracorpuscular) eg G6PD deficiency
→Extrinsic
(Extracorpuscular) eg Delayed haemolytic transfusion reaction, Infections