Su1220 Rectal Bleeding Accurately Reflects Level of Mucosal Inflammation in Patients With Ulcerative Colitis

G A A b st ra ct s versus HC (77.6 [36.9-141.0] vs 25.5 [17.8-42.8] ng/ml; p<0.001). After treatment, NGALMMP-9 levels significantly decreased in healed CD patients (69.0 [32.6-135.5] to 35.2 [9.456.1] ng/ml; p<0.001). In non-healed CD patients, NGAL-MMP-9 serum levels also decreased after treatment (100.9 [43.4-152.6] to 43.8 [27.0-96.8] ng/ml; p=0.002), however, the decrease was significantly more profound in complete healers (p=0.020) (Table1). NGALMMP-9 levels correlated with amount of neutrophils (Spearman's rho [r]=0.470, p<0.001), CRP levels (r=0.448, p<0.001), endoscopic activity (Kendall's tau [τ]=0.296, p<0.001) and histological activity (τ=0.312, p<0.001). ROC analysis defined a serum NGAL-MMP-9 cutoff level of 26.4 ng/ml corresponding to complete endoscopic healing (AUC=0.79, 58% sensitivity, 85% specificity, 56% PPV and 85% NPV) and histological healing (AUC=0.73, 63% sensitivity, 84% specificity, 50% PPV and 90% NPV). In comparison, 5 mg/L CRP discriminated complete endoscopic and histological healing with lower specificity (58% and 52%, respectively) (Figure1). Moreover, CRP was not elevated (<5 mg/L) in 33% of patients with active disease at start of treatment, whereas 81% of these patients did have elevated NGAL-MMP-9 levels. Conclusion. In the search for surrogate markers to assess mucosal healing in IBD, measurement of serum NGAL-MMP-9 complex can supplement CRP in both UC and CD. We therefore propagate that the use of NGAL-MMP-9 serum levels can be implemented in clinical practice, thereby potentially overriding the need for endoscopy.