TY - JOUR T1 - Response to: Correspondence on "PICaSSO Histologic Remission Index (PHRI) in ulcerative colitis: development of a novel simplified histological score for monitoring mucosal healing and predicting clinical outcomes and its applicability in an artificial intelligence system" by Wong <em>et al</em> JF - Gut JO - Gut SP - 807 LP - 808 DO - 10.1136/gutjnl-2022-327980 VL - 72 IS - 4 AU - Marietta Iacucci AU - Tommaso Lorenzo Parigi AU - Alina Bazarova AU - Subrata Ghosh AU - Vincenzo Villanacci AU - Xianyong Gui Y1 - 2023/04/01 UR - http://gut.bmj.com/content/72/4/807.abstract N2 - We thank the authors of this correspondence for sharing their post hoc analysis of the VARSITY trial data in UC.1 2 Prior to developing the PICaSSO Histologic Remission Index (PHRI),3 we dissected the discrete histological components and analysed their individual relationship with endoscopic features in the same cohort (unpublished data). We found that neutrophil infiltration (active inflammation), particularly that in lamina propria, had the strongest correlation with the endoscopic scores (Pearson’s r=0.64–0.74, Spearman’s ρ=0.60–0.76; p&lt;0.05) as compared with the other histological components. The total neutrophil infiltration in both epithelium and lamina propria had essentially the same correlation strength as the overall active and chronic inflammation. The other histopathological components, including chronic inflammation, basal plasmacytosis, eosinophilia and crypt architectural distortion, were also correlated but to a lesser and variable degree. When comparing differences between patients in Mayo endoscopic score (MES) 1 and 0, the former group had significantly more active inflammation (neutrophilic … ER -