What are Inflammatory Markers?

by | Sep 6, 2023 | IBD | 3 comments

What are Inflammatory Markers? Causes and Possible Solutions

Inflammatory markers are blood tests used to check for certain indicators associated with inflammation. These indicators, or biomarkers, result from the body’s natural immune response to injury, infection, or toxicity.

Doctors may prescribe a variety of these tests to help them diagnose certain diseases and conditions. For example, a person with rheumatoid arthritis or inflammatory bowel disease (IBD) is likely to have raised inflammatory markers. 

However, inflammatory markers are non-specific, which means we can’t use them on their own to identify a particular disease or condition. Instead, we use them in conjunction with other tests to diagnose and guide the treatment of the underlying cause of the inflammation.

To understand inflammatory markers, you need to understand what inflammation is, what causes it, the complex ways how the body reacts to it, and why you should consult experts.

What is inflammation?

Inflammation is the body’s natural defense against infection by foreign bodies (such as bacteria, viruses, and toxins) or injury (cell injury or tissue damage). It is a complex immune response involving the white blood cells and other parts of the immune system to protect and heal the affected area.

Inflammation is usually localized, affecting only specific areas, tissue, or cells in the body. For example, when you injure your ankle, it swells and becomes warm to the touch, red, and painful. This is all part of the healing process.

During inflammation, certain cells release special signaling molecules called cytokines. These molecules activate other cells and release more cytokines and other unique molecules.

In this way, the body alerts and activates the necessary parts of the immune system to deal with the threat. Normally, the body shuts down this immune response after successfully dealing with the injury or invasion, a case of acute inflammation. 

However, in some cases, the body continues sending out inflammation cells even when there is no apparent danger. The inflammatory cells attack and damage other cells and tissue even though there is no danger. We see this in rheumatoid arthritis, where inflammation attacks joint tissue and causes severe pain.

Other low-grade inflammatory diseases like inflammatory bowel disease (IBD) and autoimmune disorders such as lupus are also synonymous with uncontrolled inflammation. This long-term inflammation is called chronic inflammation and causes more cytokines to be present in higher concentrations than normal.

In addition to cytokines, other biomarkers associated with inflammation are:

  • Special proteins such as C-reactive protein
  • Changes in blood chemistry such as thicker hemoglobin
  • Significant changes in the levels of minerals such as iron

Understanding the complex process of inflammation is key to treating and managing conditions such as IBD.

The most important inflammatory markers: CRP, ESR, and PV

The three most commonly used inflammatory markers are C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and plasma viscosity (PV). It’s important to note that  each one measures inflammation in slightly different ways. Testing for inflammation can be done through blood work and stool samples. 

C-reactive protein

C-reactive protein is one of the cytokines released at the beginning of inflammation. It is a protein released by the liver into the blood, especially due to bacterial or viral infections (pneumonia, influenza), autoimmune diseases, and certain cancers.

The levels of CRP can increase 1,000 times at the site of the inflammation, which makes it an important early indicator. CRP is also found in patients with chronic inflammation.

Erythrocyte Sedimentation Rate (ESR)

The lab test called erythrocyte sedimentation rate (ESP) measures how quickly the red blood cells (called erythrocytes) settle to the bottom of a test tube (sedimentation). At the same time, blood plasma and white blood cells rise to the top.  Note: this test can also be referred to as sed rate by some medical professionals. 

Blood from patients with active inflammation has a faster ERP, which means their red blood cells settle more quickly in the test. ERP is measured in milliliters per hour (ml/hr) and measures the milliliters of clear plasma above the erythrocytes at the end of one hour.

Patients with active inflammation produce more of the protein fibrinogen, which causes red blood cells to clump together and settle to the bottom of a tube more quickly.

The ERP test is not considered an early indicator. It can take more than 24 hours for ERP levels to be abnormal after the start of inflammation and then persist for days after the end of the inflammation to return to normal. A highly sensitive type of CRP test is performed for quick results.

The reference ESR levels in healthy individuals (or sedimentation rate) are <15mm/hr , <20mm/hr for women, and <10mm/hr for children.

Plasma viscosity (PV) test

As the name suggests, the PV test measures the thickness of blood. Just like the ESR test, it checks for an increase in certain blood proteins that increase during inflammation.

Although it is used in many of the same conditions as the ESR test, the PV test is preferable because it:

  • Shows up on tests earlier in the disease phase than ESR
  • Has fewer false positives
  • Can be done on blood samples up to 48 hours old
  • It is a more stable and sensitive test that reveals even small change
  • It can be automated with the right technology

PV is an important indicator when diagnosing inflammation caused by bacterial infections since it tends not to show up in viral infections or connective tissue disease.

Other biomarkers used to check for inflammation

Blood cell counts

This is a standard medical test that returns information about the total number of red blood cells, white blood cells, platelets, and hemoglobin. It also gives the ratio of red blood cells to plasma in the blood, also called hematocrit.

Inflammation is associated with changes in blood cell counts. For example, it causes elevated levels of white blood cells and platelets while reducing hemoglobin levels. This test is also critical in diagnosing autoimmune diseases, certain cancers, and infections.

Fecal calprotectin

Fecal calprotectin is a more specific test used to detect inflammation in the intestines. Calprotectin is a compound found in a type of white blood cell called neutrophils which are highly active during inflammation.

Neutrophils traveling into an inflamed gastrointestinal (GI) tract release high levels of the protein calprotectin in the feces. The amount of fecal calprotectin is used to determine the activity and severity of intestinal inflammation.

However, fecal calprotectin is also not disease-specific. It only indicates intestinal inflammation, and doctors conduct further tests to confirm a diagnosis or inflammatory bowel disease (IBD).

Comprehensive metabolic panel (CMP)

This blood test measures 14 different substances and provides information about your body’s metabolism. These substances include glucose, calcium, potassium, albumin, total protein, and certain waste products of metabolism.

The CMP is a standard test that is regularly performed during checkups and can be used to gain a deeper understanding of the causes and effects of inflammation in the body.

Other identifying symptoms of inflammation

Inflammation can also cause changes in the levels of certain blood minerals and compounds. It is important to monitor these levels to keep track of active inflammation and medications that you are taking.  These are:

  • Calcium
  • Folic acid
  • Magnesium
  • Zinc
  • Electrolytes, which are measured through a CMP test

Iron is especially important since chronic inflammation often causes iron deficiency and anemia.

Tests for ferritin (iron levels), transferrin, total saturation, and total iron binding capacity (TIBC) are highly recommended in this case.

Inflammatory markers in the diagnosis and treatment of Crohn’s

Crohn’s disease is a type of inflammatory bowel disease (IBD). It causes inflammation in the lining of the gastrointestinal (GI) tract lining due to an autoimmune disorder. The use of inflammatory markers to detect and monitor the progress of the disease is vital in its management.

Remember that what you’re experiencing on the outside doesn’t necessarily reflect what’s happening on the inside. You can be symptomatic and have no inflammation, while you can have no symptoms and have active inflammation. 

Inflammatory markers provide a reliable way of keeping track of your inflammation and can help you make the right choices in your diet and lifestyle to manage the disease more effectively.

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Book your free consultation call and start your journey to remission today.

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  1. Jill

    Thanks for the info. I was diagnosed with MC a few months ago and am still trying to wrap my head around it. Would you please explain how “you can be symptomatic and have no inflammation”? I currently have MC symptoms, but recent labs showed no inflammation. I’ve always thought that inflammation was the cause of symptoms, so I’m a bit confused by this. Many thanks!

    • Ashley Hurst, R.D.

      Yes they don’t always go together! We can view inflammation through labs like fecal calprotectin and lactoferrin or a colonoscopy. There are some people that have no symptoms – yet have inflammation still present.



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