Calprotectin Stool Test
Reviewed
Also called: Fecal calprotectin test, Fecal calprotectin
A calprotectin stool test measures a protein called calprotectin in your stool to check for inflammation in your intestines. It is often used to help tell the difference between inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS). This test can detect inflammation but cannot diagnose the specific cause.
Specimen: Stool
Why this test may be ordered
- To check for inflammation in the intestines when you have long‑lasting or recurring diarrhea, belly pain, and cramping.
- To help distinguish between IBD (which involves inflammation) and IBS (which does not).
- To monitor how severe inflammation is in people already diagnosed with IBD, guide treatment choices, check if IBD is improving or worsening, and predict the chance of symptom return.
Preparation and collection
Ask your provider if you need to stop taking any medicines before the test. Never stop taking medicine without talking to your provider first. Medicines that may affect results include NSAIDs (e.g., aspirin, ibuprofen, naproxen) and proton pump inhibitors (e.g., omeprazole, esomeprazole, lansoprazole).
Stool sample collected in a clean dry container or using special paper/plastic wrap; avoid mixing with urine, toilet paper, or water. For infants, use plastic wrap inside a clean diaper. A rectal swab may be used in some cases.
There is no known risk from providing a stool sample for this test, as described by the source.
Understanding results
Your test measures the amount of calprotectin in your stool. Normal to low levels usually mean no significant inflammation. High levels suggest inflammation in your intestines. The higher the level, the more inflammation is present.
- Normal or low levels of calprotectin: It is likely that your intestines are not inflamed, and your symptoms are probably due to a non‑inflammatory condition such as irritable bowel syndrome (IBS) or an infection that is resolving. Limitation: False negatives can occur, especially in children. Next step: If symptoms persist, your provider may order other tests to find the cause.
- High levels of calprotectin: Your intestines are inflamed. Very high levels are often linked to inflammatory bowel disease (IBD) or bacterial food poisoning. Somewhat high levels may be associated with intestinal/colorectal cancer, celiac disease, certain bacterial infections, or use of NSAIDs. Limitation: Cannot diagnose the specific cause; further testing (e.g., colonoscopy) is needed to determine the condition causing the inflammation. Next step: Your provider may repeat the test in a few weeks or order a colonoscopy to look inside your intestines. High levels can be caused by IBD, certain food poisoning, infections, or other conditions.
- Cannot diagnose the specific cause of inflammation; only indicates presence or absence of intestinal inflammation.
- False negatives can occur, especially in children.
- Certain medications (NSAIDs, proton pump inhibitors) can affect results.
What to do next
If your results are high, your provider may retest in a few weeks or recommend a colonoscopy to find the cause of inflammation. If your results are normal, other tests may be done to find the cause of your symptoms.
- Do you have severe watery or bloody diarrhea with abdominal pain or cramping lasting more than a few days?
- Do you have blood, mucus, or pus in your stool?
- Do you have a feeling of urgency to move your bowels or a feeling of needing to move your bowels even when there is no stool?
- Have you had unexplained weight loss?
- Have you been diagnosed with inflammatory bowel disease (IBD) and need to monitor your condition?