Calprotectin (Stool)
Definition
Detects intestinal inflammation by measuring a protein called calprotectin in a stool sample. A high level indicates that immune system white blood cells (neutrophils) are releasing this protein into inflamed intestinal tissue.
Purpose
Its main use is to distinguish inflammatory bowel disease (IBD) from irritable bowel syndrome (IBS). IBD causes true intestinal inflammation and tissue damage; IBS produces similar symptoms but without inflammation. The test guides whether further investigation is needed.
Results
| Level | Interpretation |
|---|---|
| Normal/low | The intestines are probably not inflamed; a non-inflammatory condition |
| High | Intestinal inflammation is present; the higher the level, the more severe the inflammation |
| Very high | Often IBD or certain types of bacterial food poisoning |
| Somewhat high | Bowel/colorectal cancer, celiac disease or C. difficile infection |
Normal Values
Laboratory specific.
Risks and Limitations
False negative results can occur, especially in children. The test shows the presence of inflammation but cannot determine its cause; further investigation such as colonoscopy is needed for diagnosis.