Blood Film (Blood Smear)
See your blood cells in expert detail.
A blood film, also known as a blood smear, is a microscopic examination of your blood that gives a detailed picture of the size, shape, and appearance of your blood cells. While automated analysers count cells, a blood film allows a haematology specialist to visually inspect them, which can reveal subtle abnormalities that machines may miss. This test is often requested when a full blood count (FBC) shows unexpected results, or when a doctor suspects a blood disorder such as anaemia, infection, leukaemia, or a nutritional deficiency.
A trained phlebotomist will collect a simple blood sample, which is then spread thinly on a glass slide, stained, and examined under a microscope. The test provides valuable information about all three major blood cell lines.
Red blood cells
- Size and shape (e.g. microcytes, macrocytes, poikilocytes)
- Colour (hypochromia or hyperchromia)
- Presence of inclusions (e.g. Howell-Jolly bodies, malaria parasites)
- Distribution (e.g. rouleaux, agglutination)
White blood cells
- Total and differential count (neutrophils, lymphocytes, monocytes, eosinophils, basophils)
- Morphology (e.g. toxic granulation, hypersegmentation, blast cells)
- Presence of immature or abnormal cells
Platelets
- Number and size (e.g. thrombocytopenia, macrothrombocytes)
- Clumping or satellitism
- Presence of fragments (e.g. schistocytes)
Why it matters
A blood film can provide critical clues for diagnosing blood cancers, inherited blood disorders, infections (including malaria), and nutritional anaemias. It helps your doctor confirm or rule out conditions that may not be apparent from automated counts alone, guiding further testing and treatment decisions.
Red Blood Cell Morphology
- Red cell size (MCV)
- Red cell shape (poikilocytes, target cells, sickle cells)
- Red cell colour (MCH, MCHC)
- Red cell inclusions (Howell-Jolly bodies, Pappenheimer bodies, parasites)
White Blood Cell Morphology
- Neutrophils
- Lymphocytes
- Monocytes
- Eosinophils
- Basophils
- Abnormal or immature cells (blasts, atypical lymphocytes)
Platelet Morphology
- Platelet count
- Platelet size
- Platelet clumping
- Schistocytes
Other Findings
- Parasites (e.g. malaria)
- Rouleaux formation
- Agglutination
No special preparation required.
For blood tests, we recommend drinking plenty of water beforehand to ensure smooth sample collection. If you are taking any regular medication, continue to do so unless advised otherwise by your doctor.
Important Clinical Information:
This test is a screening tool to monitor and support your overall health. It does not replace your GP or Consultant.
Always discuss your test results, especially any abnormal results, with your GP, who can interpret them in the context of your medical history and overall health.