Sedimentation Rate Test

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Definition - What does Sedimentation Rate Test mean?

Sedimentation rate test (SRT), also called erythrocyte sedimentation rate (ESR), is a clinical test that measures the proportion of erythroctyes, or red blood cells, that settle towards the bottom of a vial inside one hour, serving as an index for marking the presence of inflammation. After drawing blood from the arm, a phlebotomist calibrates SRT values in millimeters by comparing the spatial distance between the plasma at the top of a vial and the cumulative distribution of erythrocytes falling within a range corresponding to age and gender.

SureHire explains Sedimentation Rate Test

A physician will authorize the SRT test based on symptoms a patient is experiencing including depleted appetite, pain, stiffness and swelling around joints, headaches, and weight loss, all representing factors of pathological conditions including cancer, systemic lupus erythematosus, and rheumatoid arthritis (RA). Inflammation is a homeostatic function designed to neutralize foreign antigens, creating proteins that coalesce with erythrocytes, accelerating their descent to the base of a tube in contrast with single red blood cells. SRT serves as an auxiliary testing modality combined with C-reactive protein, to arrive at a conclusive diagnosis surrounding the causal nature of the inflammation.

The SRT procedure consists of an elastic band that wraps around the upper arm, superficially exposing the vein for easy insertion of a hypodermic needle, collecting the blood into the vial for laboratory analysis. Biological and physiological variables can slow the rate at which the red blood cells fall including age, anemia, infection, kidney issues, obesity, pregnancy, and thyroid disease, skewing results against the baseline criteria. Employers can incorporate SRT testing in employee health screening given the fact that inflammation can carry etiological implications that justify regular testing in tandem with other vital health metrics including body mass index (BMI), cholesterol testing, blood glucose levels, and blood pressure testing.

According to the World Health Organization (WHO), obesity is a leading health condition that warrants consistent health checks, correlating to SRT deviations as a factor of the disorder. A physician can relay the details involving SRT test results and adjunct testing methods used for diagnostic purposes along with charting the prognosis of a particular condition.

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