Erythrocyte sedimentation rate

Written by: Solaris Diagnostics

Erythrocyte sedimentation rate

Erythrocyte sedimentation rate, otherwise known as a sed rate, is an in vitro test that is used as a marker of inflammation. ESR is the rate in mm/hour at which red blood cells in an anticoagulated standardized tube settle from plasma and other blood components. The standardized tube typically used for this test is a vertical tube called a Westergren tube. These tubes typically contain sodium citrate as an anticoagulant and were developed by Alf Vilhelm Albertsson Westergren.

There are three stages that occur during the hour that it takes to perform an ESR. They include rouleaux formation, sedimentation stage, and packing stage. When a patient is experiencing inflammatory conditions, they have an increased amount of fibrinogen and other clotting proteins in their blood, which causes increased rouleaux formation. Rouleaux is best described as a formation that happens when plasma proteins are high. Red blood cells aggregate together and form stacks, which then begin to settle at the bottom of the Westergren tube and pack together. Under normal conditions, red blood cells are negatively charged and repel each other, so the rouleaux formation does not happen and the sed rate is 0 mm/hr or close to it.

ESR is a nonspecific marker for inflammation. At Solaris Diagnostics, 1.5 mL of EDTA whole blood is aliquoted into a Westergren tube and allowed to settle for one hour. At the end of the hour, there is a definitive line between the packed red cells and the plasma, and the amount of settling is recorded in mm/hr. Abnormal ESR values include anything above 30mm/hr. A patient’s ESR will be increased in instances of rheumatoid arthritis, lupus, anemia, thyroid disease, kidney disease, multiple myeloma, systemic infections, and a host of other conditions and diseases.

Share this Article

Recent Articles

Haemophilus Influenzae

  Haemophilus influenzae is the name for any illnesses caused by the bacteria H. influenzae, the most common type of Haemophilus influenzae is Haemophilus influenzae

Read More »

Coxiella Burnetii

  Coxiella burnetii is a bacterium isolated from ticks. It is a gram-negative bacterium which causes an infection called Q fever that infects the respiratory

Read More »

Fungal Nail Infections

Fungal nail infections are common infections caused by the overgrowth of fungi which disrupt the environment of the toenail or fingernail through small cracks in

Read More »

Chlamydia Trachomatis

  Chlamydia Trachomatis is one of the more common sexually transmitted infections. The bacterial infection has a higher prevalence in populations aged 15-24, with women

Read More »

MecA

Antibiotic resistance is a serious topic in the medical community, as new drugs are developed and used for the treatment of infections these bacteria have

Read More »

Need a Reliable Diagnostic Partner?

At Solaris Diagnostics, we make it easy!

Our Results Portal allows you access patient reports quickly and securely online.

To request access to the Providers Results Portal, please complete our Provider Registration form.

Scroll to Top