Lactulose Challenge Determines Visceral Sensitivity and Severity of Symptoms in Patients With Irritable Bowel Syndrome  Boris Le Nevé, Rémi Brazeilles, Muriel Derrien, Julien Tap, Denis Guyonnet, Lena Ohman, Hans Törnblom, Magnus Simrén  Clinical Gastroenterology and Hepatology  Volume 14, Issue 2, Pages 226-233.e3 (February 2016) DOI: 10.1016/j.cgh.2015.09.039 Copyright © 2016 AGA Institute Terms and Conditions

Figure 1 GI symptom-based IBS clustering and PCA after a 25 g lactulose challenge test. (A) Cluster analysis in IBS subjects (n = 100) was performed by ascending hierarchical clustering based on the 8 meal-related GI symptoms and digestive comfort (4-h mean area under the curve scores for each individual symptom). (B) Score plot of the PCA performed for all IBS patients (n = 100) on the 8 meal-related GI symptoms and digestive comfort as active variables (4-h mean area under the curve scores for each individual symptom). LGS cluster (white dots) and HGS cluster (grey dots). LGS IBS, n = 61; HGS IBS, n = 39. Clinical Gastroenterology and Hepatology 2016 14, 226-233.e3DOI: (10.1016/j.cgh.2015.09.039) Copyright © 2016 AGA Institute Terms and Conditions

Figure 2 Intensity of rectal sensations in IBS clusters during the barostat test. Intensity (visual analog scale, 0–100 mm) of rectal sensations in IBS patients during random phasic distension at 24 mm Hg. Statistical significance was determined by 1-way analysis of variance and Benjamini–Hochberg multiplicity correction. NS for P value > .05, *P < .05, **P < .01, ***P < .001. LGS cluster is shown in white bars, and the HGS cluster is shown in grey bars. LGS IBS, n = 54; HGS IBS, n = 39. Clinical Gastroenterology and Hepatology 2016 14, 226-233.e3DOI: (10.1016/j.cgh.2015.09.039) Copyright © 2016 AGA Institute Terms and Conditions

Figure 3 Fecal microbiota diversity and composition assessed by 16S ribosomal RNA targeted pyrosequencing in IBS clusters. (A) Weighted UniFrac principal coordinate analysis of fecal microbiota from IBS clusters. (B) Microbial richness (Chao1) of fecal microbiota from IBS clusters. (C) Log10 of Firmicutes/Bacteroidetes ratio of fecal microbiota from IBS clusters. LGS cluster is shown by white dots/bars, and HGS cluster is shown by grey dots/bars. LGS IBS, n = 53; HGS IBS, n = 37. Clinical Gastroenterology and Hepatology 2016 14, 226-233.e3DOI: (10.1016/j.cgh.2015.09.039) Copyright © 2016 AGA Institute Terms and Conditions

Supplementary Figure 1 Receiver operating characteristic (ROC) curve for sensation of pain elicited by a combined nutrient and lactulose challenge test vs IBS-SSS score in IBS patients. ROC analysis was conducted to evaluate the capacity of pain elicited by a lactulose challenge test in discriminating severe IBS (IBS-SSS > 300; n = 43) from mild/moderate IBS (IBS-SSS ≤ 300; n = 55). For different values of pain, sensibility and specificity were calculated and plotted on the ROC curve. Clinical Gastroenterology and Hepatology 2016 14, 226-233.e3DOI: (10.1016/j.cgh.2015.09.039) Copyright © 2016 AGA Institute Terms and Conditions

Supplementary Figure 2 Fecal microbiota richness and diversity assessed by 16S ribosomal RNA–targeted pyrosequencing in IBS clusters. Microbial richness (number of operational taxonomic units) and diversity (Shannon) of fecal microbiota from IBS clusters. LGS cluster (white bar) and HGS cluster (grey bar). LGS IBS, n = 53; HGS IBS, n = 37. Clinical Gastroenterology and Hepatology 2016 14, 226-233.e3DOI: (10.1016/j.cgh.2015.09.039) Copyright © 2016 AGA Institute Terms and Conditions