Full Blood Count Test

Blood tests can help doctors:

  • Evaluate how well organs—such as the kidneys, liver, thyroid, and heart—are working
  • Diagnose diseases and conditions such as cancer, HIV/AIDS, diabetes, anaemia, inflammation, infection and coronary heart disease
  • Find out whether you have risk factors for heart disease
  • Check whether medicines you’re taking are working
  • Assess how well your blood is clotting

The test we offer is the Full Blood Count (also known as a Complete Blood Count).

Full Blood Count (aka Complete Blood Count)

A Full Blood Count (FBC) is an easy and very common blood test that screens for certain disorders that can affect your health.

The FBC can help detect blood diseases and disorders, such as anaemia, infections, clotting problems, blood cancers, and immune system disorders. This test measures many different parts of your blood.

When is an FBC ordered?

An FBC can be part of a routine checkup or if you have unexplained symptoms such as bleeding or bruising. An FBC can help your doctor:

  • Evaluate your overall health. An FBC can screen for a variety of potential health problems.
  • Diagnose a health problem. An FBC is often ordered when you have unexplained symptoms like weakness, tiredness, fever, redness, swelling, bruising, or bleeding.
  • Monitor a health problem. FBCs can be used to monitor your condition if you have been diagnosed with a disorder that affects blood cell counts.
  • Monitor your treatment. Certain medical treatments can affect your blood cell counts and may require regular FBCs.

An FBC measures a variety of the blood’s components and their sub-components, i.e:

  • red blood cells
  • white blood cells
  • platelets

What red blood cell (RBC) tests are carried out in an FBC?


Haemoglobin is an iron-rich protein in red blood cells that carries oxygen from your lungs to the cells of your body. Low haemoglobin levels may be a sign of anaemia, sickle cell anaemia, thalassemia or other blood disorders.

If you have diabetes, excess glucose in your blood can attach to haemoglobin and raise the level of haemoglobin A1c. This is what a diabetes test screens for – high levels of HbA1c.

Haematocrit (PCV)

Haematocrit is a measure of how much space red blood cells take up in your blood. A high haematocrit level might mean you’re dehydrated. A low haematocrit level might mean you have anaemia. Abnormal haematocrit levels also may be a sign of a blood or bone marrow disorder.

Mean Corpuscular Haemoglobin (MCH)

 An MCH value refers to the average quantity of haemoglobin present in a single red blood cell. Haemoglobin is the protein in your red blood cells that transports oxygen to the tissues of your body.

Your MCH value is related to two other values:

  1. Mean Corpuscular Volume (MCV). MCV is a measurement of the average size of your red blood cells.
  2. Mean Corpuscular Haemoglobin Concentration (MCHC). MCHC measures the average concentration of haemoglobin within RBCs.

Your MCH level can indicate underlying health issues. The normal range for MCH is between 27.5 and 33.2 picograms (pg).


An MCH below 27.5 pg is considered low. This means that there’s a low amount of haemoglobin present per red blood cell.

A low MCH value typically indicates the presence of iron deficiency anaemia. Iron is important for the production of haemoglobin. Your body absorbs a small amount of iron that you eat in order to produce haemoglobin. Some of the general causes of iron deficiency include eating a diet that is low in iron, major surgery or trauma, or blood loss.

In more rare cases, low MCH can be caused by a genetic condition called thalassemia. In this condition, production of haemoglobin is limited. This means there aren’t as many red blood cells circulating in your bloodstream.

If you have a low MCH value, you may experience the following symptoms:

  • shortness of breath
  • chest pain
  • fast heartbeat
  • fatigue or weakness
  • very pale or yellowish skin
  • headache

High MCH

An MCH value calculated above 33.2 pg is considered high. This means that there is a larger amount of haemoglobin present per red blood cell.

High MCH value can often be caused by anaemia due to a deficiency of B vitamins, particularly B-12 and folate. Both of these vitamins are required by your body in order to make red blood cells. These types of anaemia can develop if your diet is low in B vitamins or if your body does not absorb B-12 or folate properly. It’s important to be aware of the symptoms of a B-12 deficiency.

If you have a high MCH value, you may experience the following symptoms:

  • shortness of breath
  • chest pain
  • fast heartbeat
  • fatigue or weakness
  • very pale or yellowish skin
  • headache

If you have anaemia that’s due to B-12 deficiency, you may also experience:

  • tingling or “pins and needles” in your hands or feet
  • nausea or vomiting
  • bloating and gas
  • mental symptoms, such as depression or confusion

If you have anaemia due to folate deficiency, you could experience the following additional symptoms:

  • decrease in appetite
  • irritability
  • a smooth or sensitive tongue

Mean Corpuscular Volume (MCV)

Mean Corpuscular Volume (MCV) is a measure of the average size of your red blood cells. Abnormal MCV levels may be a sign of anaemia or thalassemia.

Red Blood Cell Distribution Width

The Red Cell Distribution Width (RDW) blood test measures the amount of red blood cell variation in volume and size.

You need red blood cells to carry oxygen from your lungs to every part of your body. Anything outside of the normal range in red blood cell width or volume indicates a possible problem with bodily function that in turn may affect oxygen getting to various parts of your body.

However, with certain diseases, you may still have a normal RDW.

Normal red blood cells maintain a standard size of 6 to 8 micrometers (µm) in diameter. Your RDW is elevated if the range of sizes is large.

RDW is not used as an isolated parameter when interpreting an FBC. Rather, it provides shades of meaning in the context of the haemoglobin (hgb) and mean corpuscular value (MCV).

High RDW values may mean you have a nutrient deficiency, anaemia, or other underlying condition.

The RDW test is used to help diagnose types of anaemia and other medical conditions including:

  • thalassemia, which are inherited blood disorders that can cause severe anaemia
  • diabetes mellitus
  • heart disease
  • liver disease
  • cancer

Blood Film

Also known as a peripheral blood smear, this test is included when other results are significantly abnormal. A single drop of your blood is spread in a thin layer on a glass slide then stained for inspection by microscope. Visual inspection by a medical scientist or haematologist is done to look for abnormal or immature cells.

The drop of blood on the slide contains millions of RBCs, thousands of WBCs, and hundreds of thousands of platelets. Under the microscope, the stained WBCs can be easily seen and counted to estimate the number of each type of cell present. In addition, the size, shape and general appearance of the cells can be compared to that of “normal” cells. It is possible to distinguish between the five different types of WBCs and to find their relative percentages by counting 100 consecutive cells. During this examination, the size, shape and colour (indicators of haemoglobin content) of the RBCs can be measured and the number of platelets estimated.

White blood cells (WBC)

White blood cells help your body fight infection. A FBC measures the number and types of white blood cells in your body. Any abnormal increases or decreases in the number or types of white blood cells could be a sign of infection, inflammation, or cancer.

What white blood cell (WBC) tests are carried out in an FBC?

White Cell Count (WBC)

A White Cell Count (WBC) test indicates the number of white blood cells in your blood. White blood cells protect your body from infection and disease and assist in your immune response.

Abnormal white blood cell levels may be a sign of infection, blood cancer, or an immune system disorder.

Our FBC tests the five main groups of WBC:

  1. Neutrophils. Neutrophils are a white blood cell that disposes of foreign particles and bacteria. Normally neutrophils are the highest concentration of white blood cells at up to 60%.During an immune response, neutrophils rapidly travel to the site of infection.
  2. Lymphocytes. Lymphocytes should make up approximately 25% of your total white blood cell count. They exist in two main forms: B cells and T cells, the numbers of which increases in the presence of infection.
  3. Monocytes. Monocytes are a type of white blood cell that dispose of foreign particles and bacteria. They should make up about 5 – 10% of your white blood cells.
  4. Eosinophils. Eosinophils are a white blood cell responsible for allergic responses and fighting infections. They should make up about 1 – 3% of your total white blood cell count.
  5. Basophils. Basophils are a white blood cell responsible for allergic responses and fighting infections. They should make up about 1% or less of your total white blood cell count.


Platelets are small blood cells that play an essential role in blood clotting. When you cut yourself, for example, platelets stick together to stop the bleeding. In some cases, platelet abnormalities can be a sign of a bleeding disorder or other health problem.

What platelets tests are carried out in an FBC?

Platelet Count

Platelets are blood cell fragments that help your blood clot. They are vital for ensuring correct blood clotting (coagulation) following injury by helping to seal cuts and blood vessels. A platelet count ensures levels are normal. Abnormal platelet levels may be a sign of a bleeding disorder (not enough clotting) or a thrombotic disorder (too much clotting).

Mean Platelet Volume

Mean platelet volume (MPV) is a measure of the average size of your platelets. Having a high or low MPV doesn’t mean anything on its own and should be interpreted within the context of other FBC results.

In most cases, your MPV test results is used as an indicator to decide whether or not to do additional testing, such as a bone marrow biopsy.

Also keep in mind that several things can affect your MPV, including living at a high altitude or following a vigorous exercise routine. Make sure you go over your test results with your doctor so you get the full picture.

High MPV

A high MPV means that your platelets are larger than average. This is sometimes a sign that you’re producing too many platelets.

Platelets are produced in the bone marrow and released into the bloodstream. Larger platelets are usually young and more recently released from the bone marrow. Smaller platelets are more likely to have been in circulation for a few days.

When someone has a low platelet count and a high MPV level, it suggests that the bone marrow is rapidly producing platelets. This may be because older platelets are being destroyed, so the bone marrow is trying to compensate.

Possible cancer marker

Increased MPV is associated with platelet activation, which can happen when platelets encounter tumour byproducts. Still, a high MPV doesn’t mean you have cancer. However, if you have a family history of cancer or other risk factors, your doctor might do some additional testing to make sure there are no other signs.

If you do have cancer, a high MPV may be a warning sign, depending on the results of other blood tests. Platelets can help cancer spread to other parts of the body and promote tumour growth.

A high MPV suggests increased platelet production, which is associated with reduced survival rates in several types of cancer, including:

  • lung cancer
  • ovarian cancer
  • endometrial cancer
  • colon cancer
  • kidney cancer
  • stomach cancer
  • pancreatic cancer
  • breast cancer

Keep in mind that MPV only refers to the size of your platelets, not the actual number of them. Your MPV alone doesn’t mean you have anything.

If you’re worried about cancer, familiarize yourself with these early warning signs from the National Cancer Institute:

  • skin changes
  • breast changes
  • thickening skin or lump on or under your skin
  • hoarseness or cough that doesn’t go away
  • changes in bowel habits
  • difficult or painful urination
  • appetite changes
  • trouble swallowing
  • weight gain or loss for no reason
  • abdominal pain
  • unexplained night sweats
  • unusual bleeding or discharge in urine or stool
  • feeling weak or very tired

Other causes

Depending on your other FBC results, high MPV levels can be an indicator of several conditions, such as:

  • hyperthyroidism
  • heart disease
  • diabetes
  • vitamin D deficiency
  • high blood pressure
  • stroke
  • atrial fibrillation

A low MPV means your platelets are smaller than average. Smaller platelets tend to be older, so a low MPV could mean your bone marrow isn’t producing enough new ones. Again, a low MPV on its own doesn’t mean anything.

Depending on your other FBC results, a low MPV could indicate:

  • inflammatory bowel disease, including Crohn’s disease or ulcerative colitis
  • cytotoxic medications, which are used in chemotherapy
  • aplastic anaemia

Depending on your lifestyle, a high or low MPV may be completely normal for you. However, based on other results from your FBC, it can signal to your doctor to do additional testing to rule out any possible underlying conditions.

On its own, though, a high or low MPV doesn’t mean anything about your risk of having cancer or a certain type of disease.

Order a Full Blood Count Home Test Kit

Order a Full Blood Count Home Test Kit. Get the convenience of home testing with the reassurance of professional clinical analysis. Your results are delivered quickly and securely online.

Our Full Blood Count home blood test kit checks multiple elements of your blood to assess your general blood & immune health and ability to fight viral & bacterial infection.

This Full Blood Count Test is advised if you:

  • have symptoms of anaemia (often including fatigue, paleness, difficulty exercising)
  • think you may have a bacterial or viral infection
  • want to check the general health of your blood

What’s included in the test kit?

  1. Gentle fingerprick blood testing kit
  2. FREE post & packaging
  3. Results usually within 24 Hours
  4. Accredited laboratory testing by clinical professionals
  5. Personalised report with detailed guidance in your online, secure dashboard
  6. The same accuracy and quality as your GP or hospital

What is tested?

  1. Red cell count
  2. Red cell distribution width
  3. Haemoglobin
  4. Haematocrit
  5. Mean corpuscular haemoglobin
  6. Mean corpuscular haemoglobin concentration
  7. Mean corpuscular volume
  8. Blood film
  9. White cell count
  10. Basophils
  11. Eosinophils
  12. Lymphocytes
  13. Monocytes
  14. Neutrophils
  15. Platelet count
  16. Mean platelet volume

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SIGNIFICANCE: A blood test can measure your overall health and screen for a variety of health problems; identify potential issues early and monitor your treatment. It should be a routine part of an annual health check.

May 2, 2020