P734 A single measurement of fecal calprotectin, particularly if combined with hemoglobin and C-reactive protein levels, predicts Crohn’s disease prognosis - a prospective study

Abstract

Abstract Background Early flare prediction is essential for the timely management of Crohn’s disease (CD) patients, allowing to optimize the available therapeutic toolbox and to decrease the disease burden. We aimed to evaluate the performance of readily available biomarkers (when evaluated at least once or more frequently during follow-up) and to develop risk matrices to predict CD progression. Methods CD patients receiving infliximab (IFX) as maintenance therapy (n=289) were followed up for 24 months; those patients were enrolled in DIRECT, a prospective, multicenter real-world study. Disease progression was evaluated using two composite outcomes incorporating clinical and drug-related factors, the first including also IFX dose and/or frequency adjustments. Univariate and multivariable logistic regressions were used to calculate the odds ratios (OR) and to develop risk matrices. Results The isolated presence of anemia at least once during follow-up was a significant predictor of disease progression (OR 2.436 and 3.396 [p≤0.001] for composite outcomes 1 and 2, respectively), regardless of confounding factors. Levels of C-reactive protein (CRP) above 10.0 mg/L or fecal calprotectin (FC) above 500.0 µg/g, in at least one visit, were also significant predictors, while milder elevations (3.1-10.0 mg/L and 250.1-500.0 µg/g) were only relevant when found in at least two visits (consecutive or not). The risk matrices combining the different non-invasive biomarkers had a good ability to predict CD progression. Indeed, patients simultaneously presenting anemia, CRP>10 mg/dL and FC>500.0 µg/g at least once had a probability of disease progression that ranged between 42 and 63%. Conclusion The combined evaluation of FC, hemoglobin, and CRP in at least one time point and their incorporation into risk matrices seems to be the optimal strategy for CD management, as data from additional visits did not meaningfully influence the predictions and may delay decision-making. This is one of the first studies developing risk matrices to predict the occurrence of composite outcomes in CD patients, providing an easily applicable tool for CD clinical management.