P135. Fecal calprotectin more accurately reflects endoscopic activity of ulcerative colitis than the Lichtiger Index, CRP or blood leukocytes
A. Schoepfer1, C. Beglinger2, A. Straumann2, E. Safroneeva3, Y. Romero4, D. Armstrong5, C. Schmidt6, M. Trummler7, V. Pittet8, S. Vavricka9
1University hospital Lausanne, Switzerland; 2University hospital Basel, Switzerland; 3Institute of Social and Preventive Medicine Universit of Bern, Switzerland; 4Mayo Clinic Rochester MN, United States; 5McMaster University, Hamilton, ON, Gastroenterology, Canada; 6Univesity of Jena, Jena, Germany; 7Bioanalytic Medical Laboraties, Lucerne, Switzerland; 8Institute of Social and Preventive Medicine Lausanne, Lausanne, Switzerland; 9University Hospital Zurich, Zurich, Switzerland
Background: Thus far, the correlation of noninvasive markers with endoscopic activity in ulcerative colitis (UC) according to the modified Baron Index is unknown. We aimed to evaluate the correlation between endoscopic activity and fecal calprotectin (FC), C‑reactive protein (CRP), blood leukocytes, and the Lichtiger Index (clinical score).
Methods: UC patients undergoing complete colonoscopy were prospectively enrolled and scored clinically and endoscopically in an independent fashion. Fecal and blood samples were analyzed in UC patients and controls.
Results: We enrolled 228 UC patients and 52 controls. Endoscopic disease activity correlated best with FC (Spearman's rank correlation coefficient r = 0.821), followed by the Lichtiger Index (r = 0.682), CRP (r = 0.556), and leukocytes (r = 0.401). FC was the only marker discriminating between different grades of endoscopic activity (grade 0, 20±11 µg/g; grade 1, 44±34 µg/g; grade 2, 111±74 µg/g; grade 3, 330±332 µg/g; grade 4, 659±319 µg/g; P = 0.0018 for discriminating grade 0 vs. 1 and P < 0.001 for discriminating all other grades). FC had the highest overall accuracy (91%) to detect endoscopically active disease (modified Baron Index ≥2), followed by the Lichtiger Index of ≥4 (77%), CRP larger than 5 mg/L (69%) and blood leukocytosis (58%).
Conclusions: FC better correlated with the endoscopic disease activity than clinical activity, CRP, and blood leukocytes. The strong correlation with endoscopic disease activity suggests that FC represents a useful biomarker for noninvasive monitoring of disease activity in UC patients.