The peripheral blood film
Anisocytosis
- Variation in RBC size
- Seen in meglaoblastic anaemia, thalassaemia and iron deficient anaemia
Acanthocytes
- RBCs that show many spicules due to an unstable red cell membrane lipid structure
- Seen in abetalipoproteinaemia
Basophilic RBC stippling
- Denatured RNA found in RBCs, indicating accelerated erythropoiesis or defective HB synthesis
- Seen in;
- Lead poisoning
- Megaloblastic anaemia
- Myelodysplasia
- Liver disease
- Haemoglobinopathies e.g. thalassaemia
Blasts
- Nucleated precursor cells
- Seen in myelofibrosis, leukaemia, malignant infiltration by carcinoma
Howell-Jolly bodies
- DNA nuclear remnants in RBCs - normally removed by the spleen
- Seen in post-splenectomy or hyposplenism - e.g. sickle cell disease, coeliac disease, UC/Crohn’s. myeloproliferative disease, amyloid
Hypochromia
- Less dense staining of RBC due to reduced Hb synthesis
- Seen in iron deficient anaemia, thalassaemia, sideroblastic anaemia
Left shift
- Immature neutrophils are sent out of the BM
- Seen in infection
Leucoerythoblastic anaemia
- Immature cells due to marrow infiltration e.g. malignancy when these cells are displaced
- Also seen in anorexia, sepsis, severe haemolysis
Leukaenoid reaction
- Marked leukocytosis
- Seen in severe illness
Pappenheimer bodies
- Granules of siderocytes containing iron
- Seen in lead poisoning, carcinomatosis, post-splenectomy
Poikilocytosis
- Variation in RBC shape
- Seen in iron deficient anaemia, myelofibrosis, thalassaemia
Polychromasia
- RBC of different ages stain unevenly (young are bluer)
- This is a response to bleeding, haemolysis or marrow infiltration
Reticulocytes
- Young, larger RBCs signifying active erythopoiesis
- Increased in haemolysis and haemorrhage
Right shift
- Hypermature white cells - hypersegmented polymorphs
- Seen in megaloblastic anaemia, uraemia and liver disease
Rouleaux formation
- Red cells stack on each other
- Seen in chronic inflammation, paraproteinaemia, myeloma
Spherocytes
- Spherical cells found in hereditary spherocytosis and autoimmune haemolytic anaemia
Shistocytes
- Fragmented RBCs sliced by fibrin bands in intravascular haemolysis
- Seen in;
- Microangiopathic anaemia
- DIC
- Haemolytic uraemic syndrome
- Thrombotic thrombocytopenic purpura
- Pre-eclampsia
Target cells
- These are RBCs with central staining, a ring of pallor and an outer ring of staining seen in liver disease, hyposplenism, thalassaemia