Figure 1: Subtyping patients using the biomarker fecal calprotectin identifies risk factors for pre-IBD.

(A) Levels of fecal calprotectin were measured in healthy subjects (control) and subjects with symptoms of IBS. IBS participants were sub-grouped into those with normal fecal calprotectin levels (IBS) and elevated fecal calprotectin levels (pre-IBD). (B) Levels of fecal myeloperoxidase (MPO) was measured in patients by ELISA. (C) The graph shows the percentage of IBS patients or pre-IBD patients that had stool forms consistent with IBS-C, IBS-D or IBS-M. (D) Fecal calprotectin levels in patients with PI-IBS and in patients without a history of infection (Non-PI-IBS). (E) Fraction of subjects with a history of antibiotic usage within one year. (F) Daily fat intake was determined by calculating nutrient density and expressed as intake / 1000kcal. (G) Relative abundance of Proteobacteria was determined by microbiota profiling from feces. (H) The cladogram shows differences in taxa composition determined by microbiota profiling of feces of IBS patients and pre-IBD patients. Green, elevated in pre-IBD compared to IBS; Red, reduced in pre-IBD compared to IBS. (A and B) Each symbol represents data from one individual subject. (C-F) Bars represent mean ± standard deviation. (G) The boxes in the Whisker blot represent the 1^st to 3rd quartile ranges and the horizontal lines represent the median value. The bars in the whisker blot represent the minimum and maximum value in each group. *, P<0.05; NS, P>0.05. P values were calculated by one-way ANOVA followed by Bonferroni multiple comparison test (F), by Kruskal–Wallis rank test followed by Dunn’s test (A-B, D, G) or by chi square test for categorical data (C,E). See also Figure S1, S2 and S3 and Table S1, S2, S3, S4, S5 and S6