Musculoskeletal clinicians often suggest that patients require blood tests in order for a diagnosis to be made, a condition to be excluded or to repeat a test that monitors a particular situation. Here is some information about the most common types of blood test that are routinely requested.
A Full Blood Count (FBC) is a test that identifies the different types and numbers of cells in your blood. It is a good all-round measure of health. This test can help your doctor decide whether you have anaemia (lack of haemoglobin), whether you have normal white blood cells (which help to fight infection) and normal platelets (cells that clot the blood).
An Erythrocyte Sedimentation Rate (ESR) test screens for inflammation or infection. When you are unwell, whether you have a sore throat, arthritis or almost any other problem, the ESR is raised. The ESR test is often used to monitor whether your treatment is working.
The Anti Nuclear Antibody (ANA) test is ordered to help screen for autoimmune disorders and is most often used as one of the tests to diagnose systemic lupus erythematosus (SLE). Depending on the person’s symptoms and the suspected diagnosis, ANA may be ordered along with one or more other autoantibody tests. Other laboratory tests associated with presence of inflammation, such as erythrocyte sedimentation rate (ESR) and/or C-reactive protein (CRP), may also be ordered. ANA may be followed by additional tests that are considered subsets of the general ANA test and that are used in conjunction with the person’s clinical history to help rule out a diagnosis of other autoimmune disorders.
An International Normalised Ratio (INR) test will assess whether your blood is clotting normally. It also measures the effect of Warfarin therapy, a drug used to slow down the blood clotting process and help prevent thrombosis.
An Activated Partial Thromboplastin Time (APTT) test is another means of assessing whether your blood is clotting normally.
Elecs (Urea and Electrolytes) is a common test which helps to assess the body’s general condition. It is frequently used to assess whether the kidneys are working properly or to monitor people who take various tablets such as blood pressure medication.
A Liver Function Test (LFT) measures various proteins, enzymes and waste products made or processed by the liver. It helps to determine whether someone may have gall stones, and can identify problems with the liver, such as hepatitis. Some medication can cause liver function tests to become abnormal.
A Glucose test measures how much sugar is in the blood. High levels of glucose in the blood can be a sign of diabetes.
Thyroid Function Tests (TFT [TSH]) look at the activity of the thyroid gland, or levels of thyroid hormone if you are taking supplements. Thyroid hormones control gland production of energy by cells.
A CRP (C-reactive Protein) test measures the concentration in the blood of a protein that indicates inflammation caused by illness, for example during a flare up of rheumatoid arthritis.
A Prot EP (Protein Electrophoresis) test measures different proteins in the blood. Electrophoresis allows us to see proteins such as albumin, which carries substances around the blood and antibodies to infections.
Latex RF is a blood test for rheumatoid factor, a type of antibody present in the blood of some people who have Rheumatoid Arthritis, which causes inflammation of the joints.
A PSA (Prostate Specific Antigen) test is a way of checking the activity of the prostate gland. A high levels of PSA may be a sign of cancer, but it is often raised in other non-cancerous prostate conditions, or if you have an infection. It is not a perfect test for prostate cancer, however, so if your test result is not normal, you will probably need another sort of test, called a biopsy, to be sure whether or not cancer is present.
Amylase is a test that mainly helps to diagnose or monitor diseases of the pancreas. The pancreas helps with digestion and controls blood sugar levels.
Specific things that are tested for in bloods include:
B12 and Folate, which are vitamins needed to make red blood cells. Low levels of Vitamin B12 and folate are associated with a type of anaemia, memory loss and depression.
Ferritin, a protein that stores iron in the body and is important in red blood cell production. Low levels can lead to anaemia.
Cardiac Enzymes (Card Enz), which can be released into the blood by damage to all muscles. As the heart is a muscle, measurement of cardiac enzymes can be used to diagnose a heart attack
Bone Profile, which measures proteins, minerals and enzymes involved in bone turnover. Bone reabsorption is increased by some diseases and these tests can indicate problems with bone.
Cholesterol (Chol), a soft, fatty substance present in all parts of the body. With time, these fats may deposit on the walls of blood vessels so they become narrower, increasing risk of circulatory problems and heart disease. A cholesterol blood test can help determine your risk of developing these.
Urate, a breakdown product of DNA and RNA usually passed out of the body in urine. If the urate level in the blood builds up, it can crystalise and cause inflammation in the joints – a condition called Gout. A urate blood test can help diagnose Gout and monitor the response to treatment.
If you have specific questions about any blood tests that you are having, you should discuss this with the requesting clinician.