ESR (Erythrocyte Sed. Rate)
What Is This Test?
The ESR (Erythrocyte Sedimentation Rate) test is a simple blood test that measures how quickly red blood cells (erythrocytes) settle to the bottom of a test tube within one hour. A faster-than-normal sedimentation rate may indicate inflammation somewhere in the body.
ESR is a non-specific marker of inflammation, meaning it can suggest the presence of inflammation but cannot identify its exact cause. It is commonly used along with other tests, such as CRP (C-Reactive Protein) and Complete Blood Count (CBC), to help diagnose and monitor inflammatory and autoimmune conditions.
Why this test is performed?
Doctors may recommend the ESR test to:
- Detect inflammation in the body
- Help diagnose autoimmune diseases
- Investigate persistent fever of unknown origin
- Evaluate chronic infections
- Monitor rheumatoid arthritis or lupus
- Monitor treatment response in inflammatory diseases
- Assess conditions such as temporal arteritis and polymyalgia rheumatica
- Support the diagnosis of certain cancers and chronic illnesses
Test Preparation
- No special preparation is usually required.
- You can eat and drink normally unless advised otherwise.
- Inform your doctor about any medications, as some medicines may affect ESR results.
- Tell your healthcare provider if you are pregnant or have anemia, as these conditions can influence the result.
Medical disclaimer
This article is for general information and education only. It is not medical advice, does not create a doctor–patient relationship, and is not a substitute for consultation with a qualified doctor who has assessed your individual situation. Never delay seeking medical advice because of something you have read here.
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