3 Flashcards
characteristic features of haemolytic anaemia
- Low haemoglobin
- High reticulocytes
- High bilirubin
- Palpable spleen
Features of the compensated haemolytic state
- Normal haemoglobin
- Elevated bilirubin (unconjugated)
- Increased reticulocyte count
- jaundice
Hereditary spherocytosis
- Autosomal dominant (structural defect)
- RBCs are spherocytic & polychromatic (increased reticulocytes)
- Jaundice – often presents in the neonatal period
- Splenomegaly
Abnormalities of RBC enzymes
1) Pyruvate Kinase Deficiency Anaemia (autosomal recessive)
2) Glucose 6 phosphate dehydrogenase deficiency (X-linked recessive)
Causes of Congenital Haemolytic Anaemia
1) Haemoglobinopathies
2) Cell membrane defects - Hereditary spherocytosis
3) Enzyme defects - Pyruvate Kinase Deficiency Anaemia and G6PD deficiency
Causes of Acquired Haemolytic Anaemia
1) Isoimmune - HDN
2) Autoimmune - AIHA
3) Non-immune - Drug induced
4) Non-immune - fragmentation haemolysis (e.g. HUS, mechanical heart valve malfunction)
Drug Induced AIHA
1) Acting as a hapten
2) Immune Complex (Innocent Bystander)
3) Autoimmune
Which conditions will elicit a positive Direct Coombs Test?
1) AIHI
2) HDN
Uses of the Indirect Coombs Test
Forms the basis of the CROSSMATCH/ Group and Save tests
Hypochromic microcytic
poorly haemoglobinised and small RBC (low MCH and low MCV)
Seen in:
- IDA
- ACD
- thalassaemia trai
MCV
mean corpuscular volume
= RBC size
MCH
Mean corpuscular Hb content
Reticulocytes
Immature RBCs.
Normally form <2% of RBCs.
No nucleus but some persisting RNA
Polychromatic (blue-purple) appearance in the blood film
Rouleaux
RBC columns
seen in samples with raised globulin or raised fibrinogen levels
e.g. myeloma, chronic inflammation/infection
Spherocytes
erythrocytes that are sphere-shaped rather than bi-concave disc shaped
seen in haemolysis particularly
autoimmune haemolytic anaemia (AIHA) and hereditary
spherocytosis
Howell-Jolly Bodies
Nuclear fragments in RBC
Seen in hyposplenic patients
Macrocytes
large RBC (increased MCV)
Seen in B12/folate deficiency, hepatic disease, hypothyroidism.
Anisopoiklocytosis
variance in size (anisocytosis) and shape (poikilocytosis) of a red blood cell
seen in B12/folate deficiency
When would you see RBC fragmentation?
in mechanical haemolytic anaemias
eg prosthetic valve malfunction
Megaloblasts
abnormal nucleated RBC precursors seen in B12 or Folate deficiency
Bone marrow Trephine Biopsy
Removal of core of Bone and Marrow
provides detail on architecture and infiltration
Leukaemic Blasts
abnormal primitive blast cells that are found in the bone
marrow (and often also in the peripheral blood )
Seen in Acute leukaemia and poor prognosis Myelodysplastic syndromes
Name 3 Myeloproliferative disorders
Essential thrombocythaemia
Polycythaemia vera
myelofibrosis
Myeloma
Malignant proliferation of Plasma Cells in the Bone Marrow.
NB: this is a Lymphoproliferative disease NOT a
Myeloproliferative Disease
