D-dimer, Plasma or Serum, Mass Concentration

What Is D-dimer Used For?

Doctors use D-dimer testing primarily to diagnose or evaluate conditions involving abnormal blood clotting, such as deep vein thrombosis (DVT) or pulmonary embolism. It can also help monitor patients on blood thinners or those with clotting disorders like disseminated intravascular coagulation (DIC).

How Is the Test Performed?

A small blood sample is taken from a vein, usually in your arm. The blood is then processed to separate plasma or serum, where the D-dimer levels are measured using a specialized lab technique. The test is quick and typically requires no special preparation beyond standard blood draw precautions.

What Does a High or Low D-dimer Mean?

A high D-dimer level often suggests recent clot formation or increased clotting activity, which may indicate conditions like DVT, pulmonary embolism, or other clotting disorders. A low or normal level usually means no significant clotting activity is present. However, a normal result does not definitively rule out all clotting risks, so doctors may still use other tests or clinical judgment.

When Might You Need This Test?

You may need a D-dimer test if you have symptoms like leg swelling, pain, or shortness of breath, which could signal a blood clot. Doctors may also order it for patients with risk factors for clotting, such as recent surgery, long periods of inactivity, or a history of clotting disorders.