Fecal Clostridiales distribution and short-chain fatty acids reflect bowel habits in irritable bowel syndrome.

Irritable bowel syndrome (IBS), a common functional gastrointestinal disorder, is classified according to bowel habits as IBS with constipation (IBS-C), with diarrhea (IBS-D), with alternating constipation and diarrhea (IBS-M), and unsubtyped (IBS-U). The mechanisms leading to the different IBS forms are mostly unknown. This study aims to evaluate whether specific fecal bacterial taxa and/or short-chain fatty acids (SCFAs) can be used to distinguish IBS subtypes and are relevant for explaining the clinical differences between IBS subcategories. We characterized five fecal samples collected at 4-weeks intervals from 40 IBS patients by 16S rRNA gene profiling and SCFA quantification. Finally, we investigated the potential correlations in IBS subtypes between the fecal microbial signatures and host physiological and clinical parameters. We found significant differences in the distribution of Clostridiales OTUs among IBS subtypes and reduced levels of SCFAs in IBS-C compared to IBS-U and IBS-D patients. Correlation analyses showed that the diverse representation of Clostridiales OTUs between IBS subtypes was associated with altered levels of SCFAs; furthermore, the same OTUs and SCFAs were associated with the fecal cytokine levels and stool consistency. Our results suggest that intestinal Clostridiales and SCFAs might serve as potential mechanistic biomarkers of IBS subtypes and represent therapeutic targets.

Can calprotectin predict relapse risk in inflammatory bowel disease?

OBJECTIVE: Assessing the clinical course of inflammatory bowel disease (IBD) patients consists of periodical clinical evaluations and laboratory tests. We aimed to assess the role of calprotectin tests in predicting clinical relapse in IBD patients. METHODS: Ninety-seven patients with ulcerative colitis (UC) and 65 with Crohn's disease (CD) in clinical remission were prospectively included in the study. A 10-g stool sample was collected for calprotectin assay. The cutoff level was set at 130 mg/kg of feces. Patients were followed up for 1 yr after the test or until relapse. The cumulative proportion of relapses was estimated by the Kaplan-Meier analysis. Statistics for equality of survival distribution were tested using the log-rank test. RESULTS: The calprotectin test was positive in 44 UC patients and 26 of them relapsed within a year, while 11 of 53 UC patients with a negative calprotectin test relapsed within the same time frame. Thirty CD patients had a positive calprotectin test and 13 of them relapsed within a year, as did 7 of the 35 with a negative test result. A significant correlation emerged between a positive calprotectin test and the probability of relapse in UC patients (P= 0.000). In CD patients, only cases of colonic CD showed a significant correlation between a positive calprotectin test and the probability of relapse, i.e., 6 colonic CD patients were positive for the calprotectin test and 4 relapsed (P= 0.02). CONCLUSIONS: Measuring calprotectin may help to identify UC and colonic CD patients at higher risk of clinical relapse.

The impact of Endocuff-assisted colonoscopy on adenoma detection in an organized screening program.

BACKGROUND AND STUDY AIMS: Colorectal cancer (CRC) screening with biennial fecal occult blood test has been shown to reduce CRC mortality. For the effectiveness of the CRC screening program is crucial that a high-quality colonoscopy with a high adenoma detection rate (ADR) be performed. To improve ADR, various endoscopic devices have been developed. Endocuff, an endoscopic cap with finger-like projections, has been shown to improve ADR. The aim of this study was to compare in an organized CRC screening program ADR, advanced adenoma detection rate (AADR) and mean number of adenomas per patient (MAP) using standard colonoscopy (SC) and Endocuff-assisted colonoscopy (EAC). PATIENTS AND METHODS: We compared performance of SC (in 2014) and EAC (in 2015) in consecutive participants in an organized CRC screening program. RESULTS: SC and EAC were performed in 546 (284 males) and 519 (293 males) subjects, respectively (mean age 60 years). Cecal intubation rate was 97.4 % for SC and 97.1 % for EAC and not significantly different ( P  = 0.7). ADR was 47 % for SC and 52 % for EAC, P  = 0.1. MAP in SC and EAC were 0.87 (range: 0 - 7) and 1.11 (range: 0 - 13) respectively, P  = 0.02. AADR rate was 25 % and 23 % for SC and EAC, respectively, P  = 0.5. CONCLUSION: Endocuff-assisted colonoscopy does not improve the number of patients with at least one adenoma but it may increase the number of detected adenomas per procedure.

Diagnostic value of faecal calprotectin in unselected outpatients referred for colonoscopy: A multicenter prospective study.

OBJECTIVES: To evaluate the role of faecal calprotectin in consecutive outpatients referred for colonoscopy. METHODS: Outpatients undergoing colonoscopy at five participating institutions were eligible. Demographic and clinical data were collected. Faecal samples were tested at a single laboratory by means of a commercially available kit. RESULTS: We consecutively enrolled 870 patients. Mean levels of calprotectin were significantly higher in patients with neoplastic and inflammatory disorders when compared with subjects with a normal colonoscopy or trivial endoscopic findings. Elevated calprotectin levels (>50mg/dl) were detected in 85% of patients with colorectal cancer, and 81% of those with inflammatory conditions but also in 37% of patients with normal or trivial endoscopic findings. In patients referred for chronic diarrhoea, sensitivity and negative predictive value were 100% in detecting either any organic colonic disease. In patients referred for symptoms of "suspected functional origin" sensitivity and negative predictive value for colorectal cancer were also 100%. CONCLUSIONS: In unselected outpatients referred for colonoscopy, a single measurement of faecal calprotectin is not sufficiently accurate to identify those with significant colorectal disease. However, a normal result can help rule out organic disease among patients with diarrhoea and those with abdominal pain and/or constipation.

Non-invasive investigation in patients with inflammatory joint disease.

Gut inflammation can occur in 30%-60% of patients with spondyloarthropathies. However, the presence of such gut inflammation is underestimated, only 27% of patients with histological evidence of gut inflammation have intestinal symptoms, but subclinical gut inflammation is documented in two-thirds of patients with inflammatory joint disease. There are common genetic and immunological mechanisms behind concomitant inflammation in the joints and intestinal tract. A number of blood tests, e.g. erythrocyte sedimentation rate, orosomucoid, C-reactive protein, and white cell and platelet counts, are probably the most commonly used laboratory markers of inflammatory disease, however, these tests are difficult to interpret in arthropathies associated with gut inflammation, since any increases in their blood levels might be attributable to either the joint disease or to gut inflammation. Consequently, it would be useful to have a marker capable of separately identifying gut inflammation. Fecal proteins, which are indirect markers of neutrophil migration in the gut wall, and intestinal permeability, seem to be ideal for monitoring intestinal inflammation: they are easy to measure non-invasively and are specific for intestinal disease in the absence of gastrointestinal infections. Alongside the traditional markers for characterizing intestinal inflammation, there are also antibodies, in all probability generated by the immune response to microbial antigens and auto-antigens, which have proved useful in establishing the diagnosis and assessing the severity of the condition, as well as the prognosis and the risk of complications. In short, non-invasive investigations on the gut in patients with rheumatic disease may be useful in clinical practice for a preliminary assessment of patients with suspected intestinal disease.

Calprotectin and lactoferrin in the assessment of intestinal inflammation and organic disease.

BACKGROUND AND AIMS: Calprotectin and lactoferrin are specific neutrophil-derived proteins, which can be measured in the feces because they are released by cells in inflammatory conditions. We evaluated the efficacy of calprotectin and lactoferrin in detecting organic disease as assessed by colonoscopy. METHODS: The study comprised 144 patients undergoing colonoscopy for lower gastrointestinal symptoms (abdominal pain, altered bowel habits, and bloody stools) (67), or inflammatory bowel disease activity, or surveillance for dysplasia (77). A single stool sample was assayed for calprotectin and lactoferrin. The proportion of patients correctly diagnosed with each test and the relationship with endoscopic and histological findings were measured. RESULTS: Fecal excretion of calprotectin significantly correlated with the finding of colonic inflammation at endoscopy, both in ulcerative colitis and in Crohn's disease (p<0,001 and p<0,008, respectively), while lactoferrin excretion significantly correlated with histological inflammation (p=0.001 and p=0.009 respectively). Recommended cut-off values need to be adjusted in the inflammatory bowel disease group. Overall sensitivity, specificity, positive predictive value, and diagnostic efficacy were 78, 83, 86, and 80% for calprotectin and 80, 85, 87, and 81% for lactoferrin, respectively. CONCLUSIONS: Fecal calprotectin and lactoferrin appear to be equally recommendable as inflammatory disease markers in patients with lower gastrointestinal symptoms. Both tests are needed to accurately discriminate activity in inflammatory bowel disease patients.