Fecal Calprotectin: What Your Result Means

What is Fecal Calprotectin?

Calprotectin is a protein released by immune cells wherever there is inflammation. Measured in stool, it reflects how inflamed the gut lining is at that moment. Unlike invasive scope exams, a stool sample gives a direct, painless read on inflammatory activity in the bowel — which is why it has become a standard tool for monitoring Crohn's disease and ulcerative colitis.

Typical reference interval: Reference cutoffs vary by lab and assay. Generally, low values suggest an uninflamed gut; values above the lab's cutoff indicate active intestinal inflammation and warrant clinical correlation (especially in someone with IBD symptoms or diagnosis).. Laboratories differ — the interval printed on YOUR report always governs.

If your Fecal Calprotectin is high

Common reasons Fecal Calprotectin runs above the reference interval:

• Inflammatory bowel disease — Crohn's disease and ulcerative colitis are the conditions this test exists to monitor — active disease raises it sharply
• Gut infections — bacterial or parasitic intestinal infections can drive a transient rise
• NSAID-related gut injury — high-dose anti-inflammatory drug use can inflame the gut lining
• Intestinal ischemia — reduced blood flow to the bowel triggers inflammation
• Recent flare of other GI disease — any active intestinal inflammation raises fecal calprotectin

If your Fecal Calprotectin is low

Common reasons Fecal Calprotectin runs below the reference interval:

• Uninflamed gut — a low result is the reassuring outcome — no active inflammatory activity in the bowel
• Quiescent IBD — disease in remission shows low calprotectin, which is exactly the goal of treatment

Symptoms worth knowing

The test itself is symptom-free. The condition it flags produces the classic IBD symptoms — abdominal pain, frequent or urgent stools, blood or mucus in stool, and weight loss. Fecal calprotectin quantifies the inflammation behind those symptoms.

What usually happens next

1. In someone with IBD, fecal calprotectin is a monitoring tool — a rising trend helps a care team judge treatment response
2. A high result without GI symptoms may still warrant a discussion, since inflammation can precede symptoms
3. It complements (does not replace) scopes and imaging — the full picture comes from combining them

Frequently asked questions about Fecal Calprotectin results