Find out about your blood clotting with the D-Dimer test!

You've probably heard of this test called D-Dimer. Or maybe your doctor has told you to do it. So, what is D-Dimer? Why is this test so important? Let's talk about all this in detail, very simply, today. I'll explain it in a way that you can understand.

What is D-Dimer? Simply put...

Think of it this way: D-Dimer is a small piece of protein that is formed when a blood clot dissolves in your body. Normally, if you don't have a lot of blood clots forming in your body, or if the clots that do form don't dissolve, there is almost no D-Dimer in your blood. Or it is present in very small amounts.

Now, if your D-Dimer test result is positive or if your D-Dimer level is elevated , it may indicate that you have a blood clotting condition. However, it does not necessarily mean that you have that condition . Also, a D-Dimer test alone cannot tell you exactly what type of blood clotting condition you have or where the blood clot is in your body. Further testing is needed to determine that.

How does blood clotting actually happen?

Let's first understand what the normal process of blood clotting is. In fact, blood clotting is a very important and essential thing. When you get injured, this process helps to stop a lot of bleeding. Imagine, when you get an injury to a blood vessel or tissue and start bleeding, your body starts a process called ``hemostasis``. This is what limits the bleeding and eventually makes a blood clot to stop it.

During this process of ``hemostasis,`` your body makes strands of a protein called ``fibrin,`` which forms a mesh. This mesh, along with a type of cell called ``platelet,`` helps to keep the blood clot in place until the wound heals. These clots can sometimes appear as a crust on your skin or as a lump under your skin.

After your wound heals, and your body no longer needs the clot, your body produces an enzyme called ``plasmin'' to break the clot into small pieces and remove them. These pieces are called ``fibrin degradation products'' or ``fibrin split-products''. One of those pieces is called D-Dimer.

However, if you have a blood clotting disorder, you may develop blood clots even without an injury. Or, the clots that have formed may not dissolve when they should. Simply put, your body's blood clotting process is not working properly. These types of blood clots can be dangerous and even life-threatening.

So, an elevated level of D-Dimer in your blood can be a sign that your body is significantly forming and dissolving blood clots. That's why it's a sign of a blood clotting disorder.

What is the D-Dimer test used to detect?

Doctors often use a D-Dimer test to help diagnose a blood clotting disorder. The main conditions include:

• Deep Vein Thrombosis (DVT) or Venous Thrombosis: This is when a blood clot forms in a vein deep inside your body. This clot can completely or partially block the flow of blood through the vein. DVT most often occurs in the lower leg, thigh, or hip. However, it can also occur in other parts of the body, such as the arm, brain, intestines, liver, or kidneys.
• Pulmonary Embolism (PE): This is when a blood clot that has formed elsewhere in the body (usually in the leg or arm) travels through the bloodstream and becomes lodged in a blood vessel in the lungs. This is a very dangerous condition.
• Disseminated Intravascular Coagulation (DIC): In this condition, too many blood clots form in your body . This can damage organs and cause other serious complications. The D-Dimer test is used not only to diagnose DIC, but also to see how well treatment for DIC is working.
• Stroke: In this condition, which we also call "a blood clot in the brain," a blood vessel in the brain either becomes blocked or bursts.

Why do I need a D-Dimer test?

If you have symptoms of a blood clotting condition, your doctor may order a D-Dimer test. These are symptoms of conditions such as `(DVT)`, `(PE)`, `(DIC)`, `(Stroke)` mentioned above.

Most of the time, D-Dimer tests are performed in an emergency room or hospital.

What are the symptoms of deep vein thrombosis (DVT)?

A DVT usually occurs in your leg or arm. Not everyone has symptoms. However, you may experience symptoms like:

• Swelling of the leg or arm (sometimes sudden).
• Leg pain or tenderness (may only be felt when standing or walking).
• A swollen, painful sensation in the leg or arm.
• Skin redness or discoloration.
• Blood vessels under the skin appear larger than normal.

If you have these symptoms of `(DVT)`, even if you are not currently in the hospital, see your doctor as soon as possible.

What are the symptoms of pulmonary embolism (PE)?

This is an emergency. The characteristics of a `(PE)` are:

• Sudden difficulty breathing (dyspnea) or rapid breathing.
• Sharp chest pain (often worse when coughing or moving).
• Back pain.
• Cough (sometimes with blood-tinged phlegm).
• Sweating more than usual.
• Rapid heartbeat (tachycardia).
• Dizziness or fainting.

Important: If you have these `(PE)` symptoms, you should call 911 or go to the nearest emergency room immediately. This should not be delayed.

What are the symptoms of disseminated intravascular coagulation (DIC)?

Symptoms of DIC may include:

• Bleeding gums.
• Nausea and/or vomiting.
• Severe muscle pain and stomach pain.
• Convulsions.
• Less urine output than normal.

If you have already been diagnosed with DIC and are receiving treatment, your doctor may order regular D-Dimer tests to check if your treatment is working properly.

What are the symptoms of a stroke?

Paralysis is also an emergency. The symptoms are:

• Sudden numbness or weakness of the face, arm, or leg (especially on one side of the body).
• Sudden confusion, difficulty speaking, or difficulty understanding what someone is saying.
• Sudden difficulty seeing in one or both eyes.
• Sudden difficulty walking.
• Sudden dizziness, loss of balance, or loss of coordination.
• A severe headache that comes on suddenly for no reason.

Extremely important: If you or someone else experiences these symptoms of a stroke , you should call 911 or go to the nearest hospital immediately. Time is of the essence.

Who performs the D-Dimer test? How is it done?

Usually, a phlebotomist does the blood draw, including the D-Dimer test. However, any healthcare professional trained to draw blood can do it. Your blood sample is then sent to a laboratory. There, a medical laboratory scientist prepares the sample and tests it on machines called analyzers.

Do I need to do anything before the test?

No, you don't need to do anything special before a D-Dimer test. You can live normally.

What happens during the test?

D-Dimer is a blood test. So when you take a blood sample, these are the things that happen:

• You will be seated in a chair or lying on a bed. The health worker will then look at your arms and find an easy vein to draw blood from. Most often, it is on the inside of your arm, just behind your elbow.
• When a vein is found, it is cleaned and disinfected.
• Then a small needle is inserted into your vein and a blood sample is taken. This will feel like a small ant bite.
• After inserting the needle, a little blood will collect in a test tube.
• After a sufficient amount of blood has been taken for the test, the needle is removed and a piece of cotton or gauze is placed over the site to stop the bleeding.
• Then a plaster is applied to the area and the work is finished.

This whole process usually takes less than five minutes. Very quick.

What happens after the test?

After your blood sample is taken, it is sent to a laboratory. Once the test results are in, your doctor will tell you the results.

Are there any risks with the D-Dimer test?

Blood tests are a very common and necessary medical test. The risks of having a blood test are very low. You may feel a little sore or bruised where the blood was drawn. But that will quickly go away. So there's nothing to worry about.

What do the results of the D-Dimer test mean?

A blood test report, even a D-Dimer test report, usually contains information like this:

• The name of the blood test, or what was measured in your blood.
• The number or measurement of your blood test result.
• The normal range for that test.
• Information that indicates whether your result is normal, abnormal, high, low, positive, or negative.

What is a normal D-Dimer result?

There are different ways to test your D-Dimer levels in your blood. So, there is no universal range that says "this is the normal level." Your lab report will include information indicating whether your D-Dimer level is normal, low, high, positive, or negative.

If your lab report says that your D-Dimer level is low, negative, or normal , it most likely means that you do not have a blood clotting disorder.

If you have been diagnosed with Disseminated Intravascular Coagulation (DIC) and are receiving treatment, a normal or low level of D-Dimer in your blood means that your treatment is most likely working well.

What does a high D-Dimer result mean?

If your results show that your blood D-Dimer levels are higher than normal , it could mean that you have a blood clotting condition. However, as I mentioned earlier, a D-Dimer test alone cannot tell you exactly what blood clotting condition you may have or where the blood clots are in your body.

If you have been diagnosed with Disseminated Intravascular Coagulation (DIC) and are receiving treatment, a high level of D-Dimer in your blood may mean that your treatment is not working properly.

However, there are cases where D-Dimer levels can be elevated even without a blood clotting disorder. Other reasons why D-Dimer levels can be higher than normal include:

• Pregnancy.
• Heart disease.
• A recent surgery.
• An accident or injury to the body (trauma).
• An infection.

Also, D-Dimer levels tend to increase with age. If you have a condition like rheumatoid arthritis, you may get false-positive results.

So, if your results show that your D-Dimer levels are abnormal, your doctor will likely order further blood tests and/or imaging tests to make a diagnosis.

When will I know the results of the D-Dimer test?

Doctors often order D-Dimer tests in emergency situations, because blood clots can be life-threatening. If you have this test done in an emergency, your doctor will likely get the results within a few hours.

If you have a D-Dimer test to see how well your treatment is working while you are being treated for a blood clotting condition, you will likely receive the results within one or two business days.

What happens next? If the results are abnormal...

If your D-Dimer test results are abnormal, your doctor may order one or more imaging tests to determine if you have a blood clotting disorder and, if so, where the clots are. These tests include:

• Doppler ultrasound: This uses sound waves to create images of your veins (blood vessels).
• Computed tomography (CT) angiography: In this test, a doctor injects a special dye into one of your veins. This makes your blood vessels visible on a special X-ray machine.
• Lung ventilation-perfusion (V/Q) scan: This involves a ventilation (V) scan, which measures how air is flowing into your lungs, and a perfusion (Q) scan, which looks at where blood is flowing in your lungs. In both scans, a small amount of a safe radioactive substance is used to help the scanner see how well air and blood are moving through your lungs.

When should I see a doctor?

If you have symptoms of a stroke or pulmonary embolism (PE), call 911 immediately or go to the nearest emergency room. Don't delay.

If you have symptoms of a blood clot in a deep vein (Deep Vein Thrombosis - DVT), see your doctor as soon as possible.

What are the risk factors for blood clots?

Risk factors that can contribute to inappropriate or abnormal blood clot formation include:

• Having major surgery or a major physical injury (trauma).
• Sitting in one place for long periods of time (for example, sitting on long trips, or staying in bed for long periods of time).
• Taking birth control pills or hormone replacement therapy.
• Pregnancy or recent childbirth.
• Having a family history of blood clotting, or having a specific medical condition such as Factor V Leiden disease, Antiphospholipid syndrome, or Polycythemia vera.
• Having a certain type of cancer.
• The outbreak of Coronavirus Disease 2019 (COVID-19).
• Having obesity.
• Smoking.

Finally, things to remember (Take-Home Message)

It's normal to feel scared and anxious when you get an abnormal test result. But remember, an elevated D-Dimer test result doesn't necessarily mean you have a blood clotting disorder. If your results show that your D-Dimer level is high, your doctor will likely order further tests to make a diagnosis.

If you have any questions, don't be afraid to ask your doctor. Doctors are there to help you. They will explain everything to you.

I hope this information is useful to you. Stay healthy!

` D-Dimer, blood clotting, blood tests, DVT, PE, Stroke, DIC, blood clots