The key difference between CRP and SED rate is that CRP is comparatively a better and more sensitive indicator of inflammation. In contrast, the SED rate is a relatively low and less sensitive indicator of inflammation.
Inflammation is part of the natural defense mechanism in the body. It is a process where the immune system recognizes and removes harmful foreign agents. This leads to a healing process. Inflammation can be acute or chronic. Moreover, inflammation is associated with certain severe health conditions. CRP (C-reactive protein) and SED rate (erythrocyte sedimentation rate) are both indicators of inflammation in the human body.
CONTENTS
1. Overview and Key Difference
2. What is CRP
3. What is SED Rate
4. Similarities – CRP and SED Rate
5. CRP vs. SED Rate in Tabular Form
6. Summary – CRP vs. SED Rate
What is CRP?
CRP is a protein that is made by the liver. People have low levels of c-reactive protein in the bloodstream. The liver normally releases more CRP proteins into the bloodstream when people have inflammation in the body. Therefore, a high level of CRP protein indicates that people have a serious health condition that triggers inflammation. Health care providers use CRP test to diagnose infections, chronic inflammatory diseases such as rheumatoid arthritis or lupus, sepsis, risk of heart disease and the risk of a second heart attack, fungal infections, osteomyelitis, inflammatory bowel disease (IBD) and pelvic inflammatory disease (PID). Moreover, a healthcare provider may order a CRP test if a patient has a fever, chills, rapid breathing (tachypnea), rapid heart rate, nausea, and vomiting.
Generally, the normal CRP level is less than 0.9 milligrams per deciliter (mg/dL) in the blood. A minor CRP elevation can be due to cigarette smoking, common cold, depression, diabetes, insomnia, gingivitis, obesity, periodontitis, pregnancy, and recent injury. Moderate elevation of CRP may include systemic inflammations like rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) or other autoimmune conditions, myocardial infarction, pancreatitis, and bronchitis. Furthermore, marked elevation of CRP level can be due to acute bacterial infection, viral infections, systemic vasculitis, and major trauma. However, some people may experience bruising at the blood draw site, dizziness or fainting during or after the CRP test, and soreness at the blood draw site.
What is SED Rate?
SED rate, or ESR (erythrocyte sedimentation rate), is a blood test that can detect inflammatory activity in the human body. When blood is normally placed in a thin tube, red blood cells gradually settle in the bottom. In inflammation, red blood cells are clumped. These clumps are denser than individual red blood cells and settle to the bottom more quickly than in a normal situation. Moreover, the SED rate test measures the distance red blood cells fall in a thin test tube in one hour. SED rate helps diagnose unexplained fever, giant cell arteritis, polymyalgia rheumatica, temporal arteritis, rheumatoid arthritis, acute infection such as tuberculosis, chronic infection, and acute inflammation. A doctor might order a SED rate test if people have symptoms like headaches, stiff, swollen, or painful joints, pain in the shoulders, neck, or pelvis, appetite loss, and weight loss without trying.
The usual range of SED rate is 0 to 22 mm/hr for men and 0 to 29 mm/hr for women. Furthermore, the marked elevation of the SED rate means inflammation that may be linked to several conditions, such as infections, some cancers, and autoimmune diseases. The risks of doing SED rate may include slight bruising, dizziness, sores, and minor bleeding.
What are the Similarities Between CRP and SED Rate?
- CRP and SED rates are both indicators of inflammation in the human body.
- In clinical setups, both can be used to detect inflammation in the human body.
- They are blood tests.
- Both these tests may have slight risks to some people.
What is the Difference Between CRP and SED Rate?
CRP is comparatively a better and more sensitive indicator of inflammation, while the SED rate is comparatively an inferior and less sensitive indicator of inflammation. Thus, this is the key difference between CRP and SED rate. Furthermore, CRP responds more quickly to changes in the clinical situation. On the other hand, the SED rate responds less quickly to changes in the clinical condition.
The infographic below presents the differences between CRP and SED rate in tabular form for side-by-side comparison.
Summary – CRP vs. SED Rate
CRP and SED rate are blood tests to diagnose inflammation. CRP measures the C-reactive protein level in the blood. In contrast, the SED rate measures how quickly the red blood cells settle to the bottom of a test tube. Furthermore, CRP responds more rapidly to changes in the clinical situation than the SED rate. So, this summarizes the difference between CRP and SED rate.
Reference:
1. “SED Rate (Erythrocyte Sedimentation Rate).” Mayo Clinic.
2. “C-Reactive Protein (CRP) Test: What It Is, Purpose & Results.” Cleveland Clinic.
Image Courtesy:
1. “41541 2019 132 Fig1 HTML” By Caroline Hervé, Béatrice Laupèze, Giuseppe Del Giudice, Arnaud M. Didierlaurent, and Fernanda Tavares Da Silva – Hervé, C., Laupèze, B., Del Giudice, G. et al. The how’s and what’s of vaccine reactogenicity. npj Vaccines 4, 39 (2019). (CC BY 4.0) via Commons Wikimedia
2. “Erythrocyte sedimentation rate (ESR)” By Rouibi Dhia Eddine Nadjm – Own work (CC BY-SA 4.0) via Commons Wikimedia