Definition

Fibrinopeptide A is a substance released as blood clots in your body. A test can be done to measure the level of this substance in your blood.

Alternative Names

FPA

How the Test is Performed

A blood sample is needed.

How to Prepare for the Test

No special preparation is necessary.

How the Test will Feel

When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away.

Why the Test is Performed

This test is used to help diagnose severe problems with blood clotting, such as disseminated intravascular coagulation (DIC). Certain types of leukemia are associated with DIC.

Normal Results

In general, the level of fibrinopeptide A should range from 0.6 to 1.9 (mg/mL).

Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or may test different specimens. Talk to your doctor about the meaning of your specific test results.

What Abnormal Results Mean

An increased fibrinopeptide A level may be a sign of:

• Cellulitis
• DIC (disseminated intravascular coagulation)
• Leukemia at the time of diagnosis, during early treatment, and during a relapse
• Some infections
• Systemic lupus erythematosus (SLE)

Risks

There is little risk in having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Drawing blood from some people may be more difficult than from others.

Other risks associated with having blood drawn are slight, but may include:

• Excessive bleeding
• Fainting or feeling lightheaded
• Multiple punctures to locate veins
• Hematoma (blood accumulating under the skin)
• Infection (a slight risk any time the skin is broken)

References

Pai M, Moffat KA. Laboratory evaluation of hemostatic and thrombotic disorders. In: Hoffman R, Benz EJ, Silberstein LE, et al, eds. Hematology: Basic Principles and Practice. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 127.

Sarode R, Kessler CM. Coagulation and fibrinolysis. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 40.