BLOOD FILM ABNORMALITIES

BY DR SANA BUSHRA

Target cells

• These contain excess membrane or insufficient haemoglobin and are recognized as ‘target –like’ with red peripheries, central pallor and with a dot of haemoglobin at the centre

Post splenectomy Haemoglobinopathies(sickle cell,thalassemia

disease plus trait) Severe iron deficiency Obstructive jaundice

Anisocytosis

• Variation in size of erythrocytes Iron deficiency anemia Beta thalassemia Megaloblastic anemia

Howell- jolly bodies

• Dense nuclear round remnants found within erythrocytes . Remnants of DNA and RNA

Beta –thalassemia Post splenectomy Megaloblastic anemia Sometimes found in premature infants

Poikilocytosis

• Variation in shape of erythrocytes Severe iron deficiency Beta thalassemia

Heinz bodies

• Denatured hemoglobin / hemoglobin remnant stained by supravital staining seen as a dark dot in erythrocyte.

Red cell enzyme defects ( e.g G6PD deficiency , pyruvate kinase deficiency)

Drugs and chemicals causing haemolytic anaemia

Left shift and leukaemoid reactions

Less mature white cells released prematurely from the bone marrow . Careful examination may be needed to distinguish from leukemia . Also refers to increased neutrophil/lymphocyte ratio.

Sepsis ( caused by increased demand on neutrophils , less mature cells are released prematurely )

Tuberculosis Syphilis Toxoplasmosis Down syndrome

Rouleaux formation

• Erythrocytes stacked in rows one on another Inflammation Malignancy

Spherocytes

• Seen as spherical cells with no central pallor; give rise to a low MCV

Hereditary spherocytosis Immune haemolytic anemia Severe burns Post transfusion

Dimorphic blood film

• The presence of two differently sized populations of red cells , with increased red cell distribution width(RDW)

Sideroblastic anemia(bone marrow cells unable to utilise iron to form haemoglobin characterized by ring sideroblasts in bone marrow; caused by inherited and acquired causes such as lead poisoning , anti TB drugs)

Continued

Combination of iron deficiency with a B12/folate deficiency

Iron deficiency anaemia (with microcytosis) and having received a blood transfusion

Basophil stippling

• Seen as numerous small dots in the red cell due to alpha chain clumping

Lead poisoning Beta thalassemia

Tear drop cells

Acanthocytes

• Red cells with spiny projections protruding from the surface

Post splenectomy Abetalipoprotenemia