Fecal calprotectin measures neutrophil protein in a stool sample, a validated clinical marker of intestinal inflammation used in IBD monitoring and to distinguish inflammatory from many functional presentations. Consumer microbiome panels sometimes bundle calprotectin alongside sequencing; sequencing-derived inflammation scores are a separate layer and not equivalent, see Sequencing inflammation score and Gut inflammation markers.
What not to conclude
| Finding | Weak conclusion | More accurate framing |
|---|---|---|
| High calprotectin | Automatic IBD diagnosis without gastroenterology | Supports inflammatory workup in context |
| Normal calprotectin | Rules out all gut disease forever | Functional IBS still possible; retest if symptoms change |
| High sequencing inflammation + normal calprotectin | Trust the vendor score | Prefer calprotectin for neutrophilic inflammation |
| Low Faecalibacterium | Same as high calprotectin | Taxon association ≠ calprotectin |
How calprotectin appears on reports
| Context | Utility |
|---|---|
| Diarrhoea + blood/weight loss suspicion | Helps prioritize endoscopy vs functional pathway |
| Known IBD | Trend monitoring (clinical protocols) |
| Normal calprotectin + IBS symptoms | Supports functional framing with IBS subtypes |
| Bundled on DTC kit | Same test, still needs symptom correlation |
Related pages
- Reading your microbiome report
- Gut inflammation markers · IBD vs functional gut
- Red flags
- Loose stools / diarrhoea · Abdominal pain
- Multi-marker synthesis (calprotectin vs sequencing conflicts)
- Faecalibacterium prausnitzii (association only)