Blood Tests available at D2 Medical with Electronic links to St Vincent’s and St James Hospital 8.30 am to 1.30 pm Monday to Friday National Centers of Excellence
Cholesterol is a fatty substance mostly created by the liver from the fatty foods in your diet and is vital for the normal functioning of the body. Please fast from 10 pm the night before for an accurate total, LDL, HDL and triglyceride level.
Having a high level of cholesterol can contribute to an increased risk of serious problems such as heart attacks and strokes.
Blood cholesterol levels can be measured with a simple blood test. You may be asked not to eat for 12 hours before the test (which usually includes when you’re asleep) to ensure that all food is completely digested and won’t affect the result, although this isn’t always necessary.
A number of tests can be used to diagnose and monitor diabetes by checking the level of sugar (glucose) in the blood and HBAIC.
These include the:
• fasting glucose test – where the level of glucose in your blood is checked after fasting (not eating or drinking anything other than water) for at least 8 hours
• glucose tolerance test – where the level of glucose in your blood is checked after fasting, and again 2 hours later after being given a glucose drink
• HbA1C test – a test done at your GP surgery or hospital to check your average blood sugar level over the past 3 months
A number of blood tests can be carried out to help diagnose certain cancers or check if you’re at an increased risk of developing a particular type of cancer.
These include tests for:
• Prostate Specific Antigen – this can help diagnose cancer, although it can also detect other problems such as an enlarged prostate or prostatitis.
• CA125 protein – a protein called CA125 can indicate cancer, although it can also be a sign of other things such as pregnancy or pelvic inflammatory disease
A coagulation test may be used to see if your blood clots in the normal way.A type of coagulation test called the international normalised ratio (INR) is used to monitor the dose of anticoagulants.
This is another test used to help diagnose conditions that cause inflammation.
CRP is produced by the liver and if there is a higher concentration of CRP than usual, it’s a sign of inflammation in your body.
Electrolytes are minerals found in the body, including sodium, potassium and chloride, that perform jobs such as maintaining a healthy water balance in your body. Changes in the level of electrolytes can have various possible causes, including dehydration or certain medications.
This test works by measuring how long it takes for red blood cells to fall to the bottom of a test tube. The quicker they fall, the more likely it is there are high levels of inflammation. An ESR is often used to help diagnose conditions associated with inflammation. Along with other tests, an ESR can also be useful in confirming whether you have an infection
This is a test to check the types and numbers of cells in your blood, including red blood cells, white blood cells and platelets.
When the liver is damaged, it releases substances called enzymes into the blood and levels of proteins produced by the liver begin to drop.
By measuring the levels of these enzymes and proteins, it’s possible to build up a picture of how well the liver is functioning.
This test is used to test your blood for levels of thyroid-stimulating hormone (TSH), and, where needed, thyroxine and triiodothyronine (thyroid hormones). If you have low or high levels of these hormones, it could mean you have a thyroid condition.
Blood tests assess your general state of health
• check if you have an infection
• see how well certain organs, such as the liver and kidneys, are working
• screen for certain genetic conditions
Most blood tests only take a few minutes to complete and are carried out at your GP surgery or local hospital by a doctor, nurse or phlebotomist (a specialist in taking blood samples).
If we realise from the result of the tests that the thyroid is dysfunctional, and we suspect it to be autoimmune thyroid disease, we usually order thyroid antibody tests. TPO or thyroid peroxidase antibodies (TPO Ab)
The treatments that are given are to make you feel better and prevent you from being affected by the long-term effects of thyroid hormone replacement. The most sensitive marker of the status of your thyroid, which is the blood test for TSH is used to ensure that the replacement of your thyroid hormone is adequate.
We recommend that patients who have undergone hormone replacement should strive to ensure their TSH does not go out of the normal range.
When over-replacement of the thyroid hormone is done (i.e. the TSH can no longer be detected), they may be an effect causing osteoporosis and may cause the cardiovascular system to be affected after some time. We usually use a different approach when we are targeting thyroid cancer because the aim will be to keep the level of the TSH on the lower part of the normal range.
During our work, we have met patients who feel better only if their TSH is suppressed or below the normal. This does not pose any risk provided the TSH level is still detectable, and the FT3 is still normal. We have also met patients who only feel better when their TSH is slightly above the normal range. In cases like this, we usually advise the patients.
Those with hypothyroidism will not need to get the TSH test frequently, having it done once in a year is okay while those with hyperthyroidism will need more frequent tests for FT4 and FT3 depending on the treatment.
Your doctor may ask you to go for additional tests if your results are abnormal. If this is your case, do not panic, just come to us, and we will help you get tested easily.
You can meet with us and ask if you should have a blood test if:
• Your neck is swelling or thickening
• You experience symptoms that your thyroid is over- or under-active
• You notice the irregular heart rate
• You have fertility problems
• You have osteoporosis
• Your family members have had autoimmune disorders
Other reasons that should prompt you to get a thyroid function test if you
• Do not feel well after giving birth
• Have a family history of thyroid disorders, a history of postpartum thyrodism or type 1 diabetes and you are in your early stage of pregnancy, or you are planning to become pregnant
We usually advise the following people to get tested for thyroid function at least once a year or more frequently at your doctor’s advice:
• Those that are diagnosed with a thyroid disorder
• Those that have been treated before for an overactive thyroid
• Those that have had irradiation to the head and neck that preceded a surgery for cancer of the head and neck
• Those that want to begin treatment with amiodarone or lithium. This should be done 6-12 months during and 12 months after the treatment.
This test is what helps us check for blood and proteins present in the urine. We know that there are many factors like heavy physical workout and the rest, which may influence the presence of proteins in the urine. This is why we do not mind running this test over and over again to get your accurate result.
We may ask you to give us a 24-hour sample of urine collection. This will help us know the rate at which creatinine (a waste product of the breakdown of muscle tissue) is clearing form your body.
Serum Creatinine Test
This is a blood test which helps us determine if there is a creatinine build up in your blood. On normal occasion, the kidney should completely filter out this waste product, so its presence at a high level in your blood tells us that there is a problem with your kidney.
The National Kidney Foundation says if the creatinine level in the blood of men is higher than 1.2 milligrams per decilitre (mg/dL) and 1.4 mg/dL for men signifies a kidney problem.
Estimated Glomerular Filtrate
We carry out this test to know the efficiency of your kidneys in the filtration of wastes. This test works by considering different factors like the test result (mostly the level of creatinine), the gender, age, race, weight and height.
If this test produces a result that is less than 60 ml/minute/1.73m2, then it may be that you have kidney disease.
Vitamin D is important for strong and healthy bones, and can help prevent a number of diseases. Vitamin D levels in your body can be checked with a blood test. Vitamin D deficiency is common in Ireland so your doctor might ask for a test if you are at risk, or as part of a general check-up.
Your skin makes vitamin D when it is exposed to sunlight. You can also get vitamin D from food or supplements. The liver changes the vitamin D from your skin or food into a storage form called 25-hydroxy-vitamin D. It is this form that is usually measured in the vitamin D test.
Other forms of vitamin D can also be measured, depending on your specific circumstances.
Your doctor might ask you to have this test if you are at risk of being vitamin D deficient. You might also need it if you have:
• abnormal levels of minerals such as calcium phosphate or magnesium n your blood
• bone problems
• diseases that might result in, or be caused by, too much or too little vitamin D
• problems with your parathyroid gland
No special preparation is required.
You will need to discuss with your doctor what the results mean for you. Generally, a low level of 25-hydroxy-vitamin D may mean you are not getting enough vitamin D from sunlight or from food. It could also indicate problems with vitamin D absorption from your intestines, or that your liver is not making enough of this type of vitamin D.
A high level of vitamin D usually comes from taking too much in, either from pills or in food.
Abnormal levels of a type of vitamin D produced in the kidney (1,25-dihydroxy-vitamin D) can be a sign of kidney problems or a range of other conditions.
You need vitamin B12 in your blood so you can make blood cells and have your nerves function well. Vitamin B12 is also known as cobalamin.
This test measures the amount of vitamin B12 in your blood. Folate is usually tested at the same time.
Vitamin B12 come from food such as meat, poultry, seafood, milk, cheese and eggs.
Vitamin B12 is vital for making red blood cells and for cell and tissue repair. Vitamin B12 is also needed for nerve health.
Your doctor might request this test:
• to help assess anaemia (lack of red blood cells)
• as part of a pre-pregnancy health check
• to help assess nerve health
• to help check your nutritional status, especially if you are a vegan
• to help diagnose the cause of changes in your mental state or behaviour
You will need to fast for 6 – 8 hours before your blood sample is taken.
A lower than normal level of vitamin B12 means your body lacks the vitamin. However, the result does not provide information what is causing the deficiency, or the severity of that condition. Vit B12 can be caused by a wide range of conditions. It can also be caused by a vegetarian or vegan diet. You need to discuss your results with your doctor to fully understand what the results mean for you.
Both men and women make testosterone in their bodies, although men usually produce much more of it than women. A blood test for testosterone can show how much of this important sex hormone is in your body.
Testosterone is the main sex hormone produced in men. It helps make sperm, and it influences men’s sex drive. It also helps create facial and body hair, and plays a part in the development of muscles. Men make testosterone mainly in their testes, but also in their adrenal glands.
Women make a much smaller amount of testosterone in their ovaries, adrenal glands and other body tissues. Some of this breaks down to form a type of oestrogen called oestradiol.
Some testosterone is found in the blood both of men and women. A blood test for testosterone will show how much is in your body.
Your doctor might suggest a blood test for testosterone if:
• you are having problems conceiving a child – both men and women can be tested
• you are a man with a low sex drive
• you are a man with problems getting an erection
• you are a woman with masculine features, such as a lot of body hair or a low voice
• you are a boy and puberty has come very early, or is very late
Some diseases can also affect the amount of testosterone in your blood. These include diabetes, mumps and tumours on the testicles or ovaries. People who drink too much alcohol can also have low testosterone levels.
You might be asked to have a fasting test early in the morning. In that case, you should stop eating by midnight, then only have sips of water in the morning. You can usually continue to take any medications you need but check with your doctor.
Many things can affect your testosterone blood test results, including your age, your health and what’s happening with your body.
Magnesium is a metal that is found in small amounts in every cell of your body.
Magnesium is essential to many processes in your body, such as:
• producing energy from food
• enabling your muscles and nerves to work properly
• helping your cells absorb potassium and calcium
Most of the magnesium in your body comes from the food you eat. Foods high in magnesium include green vegetables (like spinach and peas), nuts and seeds, whole grains, lentils, chickpeas, beans, and some shellfish.
About half the magnesium in your body is in your bones. The rest can be found throughout your body. Only about 1 part in 100 is in your blood.
Most people get enough magnesium from their diet, so talk to your doctor before taking magnesium supplements.
Your doctor might want to do a blood test for magnesium if you:
• drink a lot of alcohol
• have an eating disorder or a poor diet
• have diabetes
• have a problem with your kidneys
• are taking magnesium or calcium supplements
• have too much, or too little, calcium or potassium in your blood
The signs and symptoms of not having enough magnesium in your blood include:
• muscle weakness, twitching muscles or muscle cramps
• extreme irritability
• irregular heartbeat
• weight loss
If you have low levels of magnesium in your blood, it could mean:
• you are not getting enough magnesium in your diet
• your intestines are not absorbing enough magnesium
• your kidneys are excreting too much of it
You don’t need to prepare for a blood test for magnesium.
Your doctor is the best person to talk to about your blood test results. You can discuss what they mean and what comes next.
If you are pregnant, your magnesium levels might be naturally low in the second or third month of your pregnancy. Whether you are pregnant or not, a result outside the normal range might not mean that you have a health problem.
Folate is an important nutrient for making normal red blood cells and for repairing cells and nerve tissue in the body. Along with vitamin B12, it is tested to check whether you have enough of these vitamins in your blood.
Folate is a nutrient that is very similar to folic acid, which is also known as vitamin B9.
Folate is usually found in food like green vegetables, fruit, dry beans and peas and many breakfast cereals. Because it is so important in normal growth, especially in developing babies, folic acid is added to bread, flour and cereals.
There are many reasons you might need a folate test:
• Low levels of folate can cause red blood cells to develop abnormally or not produce enough.
• The test can be used to investigate why you have nerve damage.
• Folate is vital for a baby’s normal brain and spinal cord development, so many women are checked for folate deficiency before falling pregnant.
You doctor might be monitoring treatment for low folate or low Vit B12
You might be asked to fast for 6 to 8 hours before the blood test is taken.
There are many possible reasons for a low folate level:• You might not be eating enough folate-containing foods.
• Your body might not be absorbing folate from food.
• Your body might be losing folate due to taking medication, or a liver or kidney condition.
• You might need more folate than usual, such as if you’re pregnant.
Some blood tests, called cardiac enzyme tests, can check whether the heart muscle is damaged, and indicate if a person has had a heart attack.
The most common test is troponin. This test has replaced other cardiac enzyme tests previously done, as it is more accurate.
Troponin is a protein found in the heart muscle. When the heart muscle is injured, troponin is released into the bloodstream and the level that can be detected goes up. This can happen during and after a heart attack. Often the test will be done more than once to monitor for damage.
You could need this type of test if your doctor suspects that you might be having, or have had, a heart attack or other kinds of damage to your heart muscle. This test might be done if there is an abnormality on a heart tracing ECG that suggests heart attack or heart muscle damage.
No preparation is needed for this test.
You should discuss the results with your doctor to understand what they mean specifically for you.
A high level of cardiac enzymes might indicate a heart attack, but your signs and symptoms, and what your ECG shows, are also necessary for a firm diagnosis.
The healthcare professional who arranges your blood test will tell you whether there are any specific instructions you need to follow before your test.
For example, depending on the type of blood test, you may be asked to:
· avoid eating or drinking anything, apart from water (fasting) for up to 12 hours.
A blood test usually involves taking a blood sample from a blood vessel in your arm.
The arm is a convenient part of the body to use because it can be easily uncovered. The usual place for a sample to be taken from is the inside of the elbow or wrist, where the veins are relatively close to the surface.
Blood samples from children are often taken from the back of the hand. Their skin may be numbed with a special spray or cream before the sample is taken.
A tight band (tourniquet) is usually put around your upper arm. This squeezes the arm, temporarily slowing down the flow of blood and causing the vein to swell. This makes it easier for a sample to be taken.
Before taking the sample, the doctor or nurse may clean the area of skin with an antiseptic wipe.
A needle attached to a syringe or special container is inserted into the vein. The syringe is used to draw out a sample of your blood. You may feel a slight pricking or scratching sensation as the needle goes in, but it shouldn’t be painful. If you don’t like needles and blood, tell the person who is taking the sample so they can make you more comfortable.
When the sample has been taken, the tourniquet will be released, and the needle will be removed. Pressure is applied to the skin for a few minutes using a cotton-wool pad. A plaster may be put on the small wound to keep it clean.
Only a small amount of blood is taken during the test so you shouldn’t feel any significant after-effects.
However, some people feel dizzy and faint during and after the test. If this has happened to you in the past, tell the person carrying out the test so they’re aware and can help you feel more comfortable.
After the test, you may have a small bruise where the needle went in. Bruises can be painful, but are usually harmless and fade over the next few days.