What causes elevated D-dimer levels? Related conditions and treatments

Overview: What do elevated D-dimer levels feel like?

D-dimer is a fragment from a fibrin protein that glues platelets together into a blood clot. The body separates platelets from fibrinogen fragments during fibrinolysis, the process by which a blood clot breaks down. One of those protein fragments is D-dimer. The body constantly forms little blood clots, so there’s always a “normal” or baseline D-dimer level in the blood, but it’s minimal. The only way to spot high D-dimer levels is from a blood test. If, on a blood test, D-dimer levels are higher than normal, this could mean there could be a blood clot (thrombus) lodged in a blood vessel. However, test results sometimes show that D-dimer levels are high, but there is no blood clot. Elevated D-dimer levels don’t feel or look like anything and do not cause any symptoms unless a person has a serious blood clotting disorder such as a pulmonary embolism, deep vein thrombosis (DVT), stroke, COVID-19, or blood clots throughout the circulatory system. Medical conditions, such as pregnancy, obesity, and infections, can also raise D-dimer levels. In those cases, people won’t know they have elevated D-dimer levels until they have a blood test.

What causes elevated D-dimer levels?

The most significant causes of elevated D-dimer levels are serious blood clot problems such as:

• Deep vein thrombosis

• Pulmonary embolism

• Stroke

• Disseminated intravascular coagulation (DIC)

DIC involves blood clots forming throughout the circulatory system. It’s an uncommon and life-threatening condition that can be caused by:

• Trauma

• Surgery

• Cancer

• Sepsis

• Complications of pregnancy or childbirth 

• Liver disease

• Pancreatitis

• Severe immune reactions, including the body’s immune reaction to severe COVID-19 infection

• Snake or spider venom

High D-dimer levels are also associated with other risk factors, but healthcare professionals consider these high D-dimer levels false positives. Though these conditions are caused by elevated D-dimer levels, they are not from a blood clotting disorder and do not require medical treatment. These conditions include:

• Advanced age

• Obesity

• Pregnancy

• Childbirth

• Cigarette smoking

• Injury

• Recent surgery

• Infection

• Heart disease

• Autoimmune disorders such as rheumatoid arthritis

RELATED: What causes blood clots? Diagnosis, prevention, and treatments,

Should I be worried about an elevated D-dimer level?

People will learn they have an elevated D-dimer level from a healthcare professional. Most people will already have been told that a D-dimer assay was drawn because there’s a risk that they have a blood clot. Before getting test results, a blood sample will be drawn by a phlebotomist and sent to a laboratory for testing. Rarely, the mishandling of the blood draw or the blood could result in a falsely elevated D-dimer test result. 

D-dimer tests are rapid and inexpensive, so they’re a great tool for determining if someone needs more testing. However, they’re not very specific to blood clots. Because of this low specificity, the D-dimer test should only be performed on patients at risk for blood clots because otherwise, the results have a high probability of returning false positives. In those cases, people will have elevated D-dimer but no blood clots.

People with obvious symptoms of a blood clot will probably not be given a D-dimer test because it won’t offer more information. Instead, they will be given other blood and imaging tests to verify there’s a blood clot and find its location.

Blood clot symptoms that require immediate medical attention include:

• Symptoms of DVT include leg swelling, leg pain, leg warmth, and red skin on one leg

• Shortness of breath, difficulty breathing, chest pain, back pain, coughing, and racing heartbeats are signs of a blood clot in the lung’s arteries (pulmonary embolism)

• Stroke is signaled by the sudden onset of symptoms such as confusion, weakness, or numbness on one side of the body—other symptoms include sudden loss of coordination, confusion, inability to speak, inability to walk normally, lightheadedness, dizziness, and severe headache

• Bleeding (nosebleeds, gum bleeding, skin bruising, wound bleeding), blood in the stool, blood in the urine, bruising, and chest pain are symptoms that blood clots are forming throughout the circulatory system (disseminated intravascular coagulation) 

If any cluster of these symptoms is experienced, go to an emergency department for immediate evaluation.

RELATED: How to recognize the signs of a stroke

How is the cause of elevated D-dimer levels diagnosed?

If there is a risk of a blood clot, the clinician will use more specific diagnostic methods than a D-dimer assay to make a diagnosis. These will include:

• Blood tests to spot more specific markers of a blood clot

• A Doppler ultrasound scan of the legs to find a blood clot in the leg

• A chest CT angiography or a ventilation/perfusion (V/Q) scan to find a blood clot in the lungs

• A CT scan or MRI of the head to find a blood clot in the brain

If there are no symptoms or any risk of a blood clot, the clinician will probably indicate that the elevated D-dimer levels are probably nothing to worry about. Still, the clinician may do a workup to make sure. This will include:

• A medical history

• A physical examination

• Blood tests to identify other markers of a blood clotting problem

Are elevated D-dimer levels contagious? 

Elevated D-dimer levels are not contagious. In some cases, high D-dimer levels may well be associated with infections such as COVID-19. However, in those cases, people will know they have an infection. For COVID-19, blood clotting and elevated D-dimer levels don’t occur until someone is severely ill and needs emergency or intensive care.

How long do elevated D-dimer levels last?

D-dimer levels will last for as long as the underlying cause. For people with blood clots, it will last until the blood stops clotting and the clots are fully dissolved. An elevated D-dimer may be a long-term condition for false positives, but it’s not harmful.

How to stop elevated D-dimer levels

There are no elevated D-dimer levels treatments because elevated D-dimer in the blood does not do any harm. However, blood clots are a serious and life-threatening disorder. If elevated D-dimer levels result from a blood clot, clinicians will treat that blood clot and try to lower the risk of other blood clots forming. Treatments will vary depending on the location of the blood clot.

Treatments for deep vein thrombosis typically involve:

• Blood thinner medications, including antithrombin activators (heparins), vitamin K antagonists such as warfarin, and oral anticoagulants

• Clot-dissolving medications called thrombolytics

A pulmonary embolism is primarily treated with: 

• Blood thinners

• Thrombolytics

• Catheter thrombolysis (in which blood clotting dissolvers are placed directly on the blood clot using a catheter)

• Thrombectomy (surgical removal of the blood clot)

• Surgical installation of a vena cava filter to prevent new blood clots from entering the heart and traveling to the lung’s arteries

Stroke is treated by:

• Stabilizing vital signs: breathing, blood pressure, temperature, and blood sugar

• Thrombolytics, usually intravenous alteplase

• Thrombectomy

• Antiplatelet treatment with aspirin

Healthcare professionals treat disseminated intravascular coagulation by focusing on the underlying cause. If blood clotting is severe, the medical team will administer blood thinners.

RELATED: Anticoagulants: uses, common brands, and safety info

Living with elevated D-dimer levels

When D-dimer levels are associated with a blood clot, serious illness, or injury that causes blood clots, healthcare providers will treat that underlying condition. D-dimer levels will return to normal when the clot dissolves and no new clots form. However, many people have elevated D-dimer levels without blood clots. D-dimer levels aren’t something to worry about if they are not severely elevated. If they’re due to a controllable issue like obesity or smoking, correcting that problem may return D-dimer levels to normal.

What’s next? Additional resources for people with elevated D-dimer levels

Test and diagnostics

• COVID-19 and D-dimer: Frequently Asked Questions, American Society of Hematology

• D-dimer, StatPearls

• D-dimer test, Cleveland Clinic

• D-dimer: what is it, testing, and more, Osmosis

Treatments

• Acute stroke, StatPearls

• Anticoagulants: uses, common brands, and safety info, SingleCare

• Deep vein thrombosis treatments and medications, SingleCare

• Disseminated intravascular coagulation, StatPearls

• Pulmonary embolism symptoms: what are the early signs of pulmonary embolism?, SingleCare

• Thrombolytics: uses, common brands, and safety info, SingleCare

Scientific studies and clinical trials

• Factors associated with positive D-dimer results in patients evaluated for pulmonary embolism, Academic Emergency Medicine

• How to recognize and manage COVID-19-associated coagulopathy, American Society of Hematology

More information on related health conditions

• What causes blood clots? Diagnosis, prevention, and treatments, SingleCare

• Deep vein thrombosis treatments and medications, SingleCare