Article Text

other Versions

Concise report
Elevated calprotectin levels reveal bowel inflammation in spondyloarthritis
  1. H Cypers1,2,
  2. G Varkas1,2,
  3. S Beeckman1,
  4. K Debusschere1,2,
  5. T Vogl3,
  6. J Roth3,
  7. M B Drennan1,2,
  8. M Lavric4,
  9. D Foell4,
  10. C A Cuvelier5,
  11. M De Vos6,
  12. J Delanghe7,
  13. F Van den Bosch1,
  14. D Elewaut1,2
  1. 1Department of Rheumatology, Ghent University Hospital, Ghent, Belgium
  2. 2Unit for Molecular Immunology and Inflammation, VIB Inflammation Research Center Ghent University, Ghent, Belgium
  3. 3Institute of Immunology, University of Münster, Münster, Germany
  4. 4Department of Pediatric Rheumatology and Immunology, University of Münster, Münster, Germany
  5. 5Department of Pathology, Ghent University, Ghent, Belgium
  6. 6Department of Gastroenterology, Ghent University Hospital, Ghent, Belgium
  7. 7Department of Clinical Chemistry, Microbiology and Immunology, Ghent University Hospital, Ghent, Belgium
  1. Correspondence to Dr Dirk Elewaut, Department of Rheumatology, Unit for Molecular Immunology and Inflammation, VIB Inflammation Research Center, Ghent University, De Pintelaan 185, Ghent 9000, Belgium; dirk.elewaut{at}


Introduction Microscopic bowel inflammation is present in up to 50% of patients with spondyloarthritis (SpA) and is associated with more severe disease. Currently no reliable biomarkers exist to identify patients at risk. Calprotectin is a sensitive marker of neutrophilic inflammation, measurable in serum and stool.

Objectives To assess whether serum and faecal calprotectin in addition to C-reactive protein (CRP) can be used to identify patients with SpA at risk of microscopic bowel inflammation.

Methods Serum calprotectin and CRP were measured in 125 patients with SpA. In 44 of these patients, faecal samples were available for calprotectin measurement. All 125 patients underwent an ileocolonoscopy to assess the presence of microscopic bowel inflammation.

Results Microscopic bowel inflammation was present in 53 (42.4%) patients with SpA. Elevated serum calprotectin and CRP were independently associated with microscopic bowel inflammation. Faecal calprotectin was also significantly higher in patients with microscopic bowel inflammation. Patients with CRP and serum calprotectin elevated had a frequency of bowel inflammation of 64% vs 25% in patients with low levels of both. When either CRP or serum calprotectin was elevated, the risk was intermediate (40%) and measuring faecal calprotectin provided further differentiation. Hence we suggest a screening approach where initially serum calprotectin and CRP are assessed and, if necessary, faecal calprotectin. The model using this scenario provided an area under the ROC curve of 74.4% for detection of bowel inflammation.

Conclusions Calprotectin measurements in stool and serum, in addition to CRP, may provide a promising strategy to identify patients with SpA at risk of bowel inflammation and could play a role in overall patient stratification.

  • Spondyloarthritis
  • Inflammation
  • Disease Activity

Statistics from

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.