Calprotectin Interpreter

Calprotectin is a protein that comes from certain white blood cells in your gut. When your intestines are inflamed (red, swollen, or irritated), these cells release more calprotectin, and it shows up in your stool (poop). A stool test measures how much is there. The result is reported as a number in micrograms per gram (µg/g). A higher number usually means more inflammation in the gut.

This test is a clue, not a diagnosis. Your doctor reads it together with your symptoms, exam, and other tests. As a general guide:

• Under 50 µg/g — usually normal. Inflammation in the gut is unlikely. This is a strong reason to feel reassured, especially if you were being checked for inflammatory bowel disease (IBD).
• 50 to 149 µg/g — mild elevation. This can be raised for many reasons. Your doctor may repeat the test or look at the trend over time.
• 150 to 249 µg/g — moderate elevation. Inflammation is more likely, and your doctor may want more tests, such as a look inside the bowel (colonoscopy).

Results of 250 µg/g or higher are in the high range and are more strongly linked to active inflammation. Different clinics and labs use slightly different cut-offs, so always follow the ranges your own doctor and lab use.

If you already have IBD, this test is very useful for tracking how you are doing over time. A single number matters less than the direction it is moving:

• A falling number often means your treatment is working and inflammation is calming down.
• A stable low number suggests your disease is well controlled.
• A rising number can be an early warning of a flare, sometimes before you feel worse. Your doctor may act on this before symptoms return.

Calprotectin can naturally vary from day to day and even between different poops on the same day, so one small change is not always meaningful.

• Follow the exact instructions from your lab or the test kit.
• Collect the sample as directed and get it to the lab or store it as told, because leaving it at room temperature too long can change the result.
• If you can, avoid NSAID pain relievers (like ibuprofen) before testing unless your doctor says otherwise, since they can raise the number.
• Tell your doctor if you have a stomach bug or are on your period, as these can affect the result.

• What does my number mean for me specifically?
• Does this change my diagnosis or my treatment?
• Should I repeat the test, and if so, when?
• Do I need a colonoscopy or other tests?
• Which of my medicines could be affecting this result?

Healthy young children, especially babies and toddlers, can normally have higher calprotectin than adults. Children's results should always be interpreted by a pediatric doctor using age-appropriate ranges.

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