Why Is My Dog Or Cat's Erythrocyte Sedimentation Rate Increased ?













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

Your Pet's Erythrocyte Sedimentation Rate = ESR or Sed Rate

See a slightly different explanation here.

The erythrocyte sedimentation rate or ESR is a very basic test that responds to inflammation anywhere in your pet's body. It measures the speed with which your pet’s red blood cells (erythrocytes=RBCs) drop to the bottom of a glass tube over a period of one hour.

This old test, is rapidly being replaced by more sophisticated ones that directly measure the amount of inflammatory agents (eg C-reactive protein, an acute phase reactant produced by your pet's liver) that rise in all sorts of inflammatory situations.

Although the ESR tells veterinarians that inflammation is present, it does not tell us where the inflammation is happening or the type. Certain blood constituents (mainly fibrinogen) speed the rate at which the blood settles (sediments) under gravity while others (the negative charge of erythrocytes) delay it.



Reason’s Your Pets Erythrocyte Sedimentation Rate Might Be Faster Higher Than Normal :

Any cause of inflammation. That could be an infection, the inflammation of moderate to severe arthritis, autoimmune disease, parasite infections, cancer or kidney disease.

Even anemia itself increases ESR. So pets with a lower than normal number of red blood cells often have faster sedimentation rates.

Reason’s My Pets Erythrocyte Sedimentation Rate Might Be Slower (Lower) Than Normal :

Diseases that alter the shape of erythrocytes can extend ESR rate test results. So can very high white blood cell (WBC) counts, disseminated intravascular coagulation (DIC), chronic heart failure or elevated blood bile salt levels.