Why Is My Dog Or Cat's Blood Fibrinogen Level Low or High ?













Ron Hines DVM PhD

To see what normal blood and urine values are, go here

For an explanation of causes of most abnormal blood and urine tests, go here

To see how tests are grouped, go here

The Fibrinogen Level In Your Pet’s Blood

When your veterinarian requests a fibrinogen level on your pet, it is usually as part of a blood clotting panel that was ordered because of concerns about uncontrolled bleeding, possible genetic tendencies of your pet to bleed or a planned major surgery.

Fibrinogen is a protein found in your dog or cat’s blood. It is produced in the pet’s liver. When it is converted to fibrin, it forms the basic structural element of blood clots.

Because of fibrinogen's importance in the clotting mechanism, you veterinarian might order the test if he/she is suspicious that you pet is bleeding due to a lack of fibrinogen.

Sometimes, you and your veterinarian are faced with unexplained anemia in your pet. Because the clotting of blood is such a complex process (the coagulation cascade) with many different stages and the interplay of many chemicals and cells; a series of tests might be required to determine exactly what is wrong. The other tests that might be ordered to sort things out are a thrombocyte count, prothrombin time (PT), partial thromboplastin time (PTT), the d-dmer test and thrombin clot time TCT.


Reasons Why Your Pet’s Blood Fibrinogen Level Might Be High :

All Inflammatory diseases or those that cause tissue damage stimulating the production of inflammatory cytokines can cause your pet's blood fibrinogen levels to rise (fibrinogen is an "acute phase reactant"). That could be a serious infection, severe gum and tooth disease, certain cancers, heart disease, severe arthritis or chronic kidney disease. It might also be high after the trauma of a car accident.

Mid-to-late pregnancy or the advanced age of your pet can also cause your pet's blood fibrinogen levels to rise.

Reasons Why Your Pet’s Blood Fibrinogen Level Might Be Low :

Disseminated Intravascular Coagulation (DIC), severe hemorrhage, liver failure, inherited deficiencies in fibrinogen production or defective (hypofibrinogenaemia) can all caused reduced blood fibrinogen levels.

Liver disease, so advanced that the pet's liver can no longer manufacture fibrinogen, or severe malnutrition can also cause low fibrinogen levels.

In emergency situations, pets are given large amounts of intravenous fluid. That additional liquid dilutes the amount of fibrinogen in the blood and can result in low fibrinogen readings.

The test's fibrinogen level results can also falsely decrease if a lavender top collection tube (EDTA tube) sat over 24 hrs before testing was performed.

Complementary Tests :

APTT (Activated Partial Thromboplastin Time) or prothrombin time (PT), thrombin clot time (TCT)