Blood Test - General Points

This leaflet gives general information about blood tests. There are separate leaflets that describe various specific types of blood test.

Blood cells, which can be seen under a microscope, make up about 40% of the blood's volume. Blood cells are made in the bone marrow by blood 'stem' cells. Blood cells are divided into three main types:

• Red cells (erythrocytes). These make blood a red colour. One drop of blood contains about five million red cells. A constant new supply of red blood cells is needed to replace old cells that break down. Millions are released into the bloodstream from the bone marrow each day. Red cells contain a chemical called haemoglobin. Haemoglobin is attracted to oxygen and the two substances can bind together. This allows oxygen to be transported by red blood cells from the lungs to all parts of the body.
• White cells (leukocytes). There are different types such as neutrophils (polymorphs), lymphocytes, eosinophils, monocytes, basophils. They are a part of the immune system and are mainly involved in combating infection.
• Platelets. These are tiny and help the blood to clot if we cut ourselves.

Tags: blood test, blood cells, blood test report

The most common blood tests are:

• Full blood count - checks for anaemia and other conditions which affect the blood cells.
• Kidney function.
• Liver function.
• Blood sugar (glucose) level.
• Blood clotting tests.
• Tests for inflammation.
• Blood cholesterol level.
• Immunology - such as checking for antibodies to certain viruses and germs (bacteria).
• Blood grouping.
• Thyroid function.

White cells (leukocytes). There are different types of white cells such as neutrophils (polymorphs), lymphocytes, eosinophils, monocytes, basophils. They are a part of the immune system and are mainly involved in combating infection.

These are their normal ratios:


> Polymorphonuclear cells: 35-80%
> Immature Polys (Bands): 0-10%
> Lymphocytes: 20-50%
> Monocytes: 2-12%
> Eosinophils: 0-7%
> Basophils: 0-2%



To improve immune system

• Don’t smoke.
• Eat a diet high in fruits, vegetables, and whole grains, and low in saturated fat.
• Exercise regularly.
• Maintain a healthy weight.
• Control your blood pressure.
• If you drink alcohol, drink only in moderation.
• Get adequate sleep.
• Take steps to avoid infection, such as washing your hands frequently and cooking meats thoroughly.
• Get regular medical screening tests for people in your age group and risk category.

Tags: polymorphs,lymphocytes

What do we test for in a full blood count?


During medical check-ups, most clinics, hospitals and labs are quite thorough. These are some of the common components of red blood cell measurements you will find:


1. RBC – this stands for Red Blood Cell or erythrocyte count. This counts the number of red blood cells that you have per litre of your blood plasma.
The normal ranges are 4.3-6.2x106/microL (male), 3.8-5.5x106/microL (female) and 3.8-5.5x106/microL (infant/child).


Women tend to have a lower RBC than males because of menstruation, but this is considered normal.


2. Hb – Haemoglobin. This measures the amount of haemoglobin in your blood. As we well know, haemoglobin is the component that carries oxygen in our red blood cells. It’s what gives our blood its red colour. If you have low haemoglobin, this means you have anaemia.


The normal ranges are 13.2-16.2g/dL (male), and 12.0-15.2g/dL (female).
3. Haematocrit (Hct) – this stands for the ratio of the volume of red cells to your whole blood. It is usually 40-52% for males, and 37-46% for females.


4. MCV (Mean Corpuscular Volume) – this is the average volume of your red blood cell. Yes, this means their size (in a way). If you have a high MCV, this may signify a certain type of disease, such as megaloblastic anaemia, where your red blood cells are huge.


5. MCH (Mean Corpuscular Haemoglobin) – the average amount of haemoglobin you have in your red blood cell. Again, another indice to signify anaemia if it’s low.


6. MCHC (Mean Corpuscular Haemoglobin Concentration) – the average concentration of haemoglobin in a volume of red blood cells. It should normally be 32-36%.

Platelet count – this measures the number of our platelets in a volume of our blood. Platelets look like little plates! They are not complete cells, but rather fragments of a cell called a megakaryocyte. They help in our blood clotting process as the front-liners to repair a wound.


The normal ranges are 140-450x103/microL.


Low platelets may signify certain disease like dengue fever, especially when you have the symptoms. Low RBC, WBC and platelets together may mean a viral illness, or – if severely depressed – something more sinister like acute myeloid leukaemia.

Thyroid function tests

Thyroid function tests are blood tests which help to check the function of the thyroid gland. They are mainly used to detect hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid).

What are thyroid function tests used for?

Thyroid function tests are usually done to find out whether the thyroid gland is working properly. This is mainly to diagnose underactive thyroid (hypothyroidism) and overactive thyroid (hyperthyroidism). Thyroid function tests can also be done to:

• Monitor treatment with thyroid replacement medicine for people who have hypothyroidism.
• Check thyroid gland function in people who are being treated for hyperthyroidism.
• Screen newborn babies for inherited problems with the thyroid.

How do thyroid function tests work?

Usually the first test to check thyroid function measures the levels of TSH in your blood. In people with hypothyroidism (underactive thyroid) the amount of TSH will usually be high. This is usually because the thyroid is not making enough T3 to stop the pituitary producing TSH. If the level of TSH is high, you will usually have further tests to check the levels of T3 and T4 in the blood.

In people with hyperthyroidism (overactive thyroid) the level of TSH will usually be low. This is usually because the thyroid gland is making too much of its hormones. When levels of T3 and T4 are high, the pituitary is 'turned off' and the amount of TSH produced is less. If you are found to have low levels of TSH you may have some more blood tests to check the levels of T3 and T4 in the blood. These tests may help doctors to find a specific cause of the low TSH.

Erythrocyte Sedimentation Rate or ESR


ESR stands for erythrocyte sedimentation rate. It is commonly called a "sed rate."
It is a test that indirectly measures how much inflammation is in the body.

Erythrocyte sedimentation rate (ESR) was determined in 180 DHF patients (dengue) and 70 patients with various viral and bacterial infections. normal range is (0 - 15)

Why the Test Is Performed

A "sed rate" is often ordered for someone who is having unexplained fevers, certain types of arthritis, muscle symptoms, or other vague symptoms that cannot be explained.
Once a diagnosis has been made, this test may be used to monitor whether the illness is becoming more active or flaring up.

This test can be used to monitor inflammatory diseases or cancer. It is a screening test, which means it cannot be used to diagnose a specific disorder.
However, it is useful for detecting and monitoring:

• Autoimmune disorders
• Certain forms of arthritis
• Inflammatory diseases that cause vague symptoms
• Tuberculosis

Recheck your blood test after 1 month.

On my last blood test, my triglycerides were 280. Should I be worried about that?

A high triglyceride level is worrisome for several reasons. It's usually accompanied by a high level of low-density lipoprotein (LDL, the so-called bad cholesterol) and a low level of high-density lipoprotein (HDL, "good" cholesterol). Very high triglycerides can damage the liver and pancreas.


TRIGLYCERIDE LEVELS
Normal: Less than 150
Borderline high: 150-199
High: 200-499
Very high: 500 or higher
(Values in milligrams per deciliter (mg/dL)


Several things can cause triglyceride levels to rise. The most common culprit is a diet rich in fatty foods and highly processed carbohydrates, followed by excess weight, smoking, and little physical activity. Other contributors include an underactive thyroid gland, kidney disease, diabetes, overproduction of the hormones aldosterone or cortisol, some medications, and some genetic conditions.

Thanks for the share this useful post.