Ashok S. Raj

Dyspepsia and the microbiome: time to focus on the small intestine.

We note with interest two recent publications in Gut regarding alterations to the gut microbiome in individuals on proton pump inhibitor (PPI) therapy.1 ,2 With PPI use, both studies observed an increase in oral bacteria in the stool. These changes overlap with those described in patients with cirrhosis of the liver.3 However, very little is known about the impact of this dysbiosis over the length of the GI tract, and how it may link to gut function. While the data from both Jackson et al 1 and Imhann et al 2 are demonstrative of a shift towards oral-associated bacteria, it is important to note that many of these bacteria have also been identified in the stomach and small intestine. Recently, we have shown that although the microbiota found in the healthy duodenum are taxonomically similar to the oral microbiota, their presence and association with the intestinal mucosa is not merely a result of luminal contamination.4 Thus, small intestinal dysbiosis and its potential impact on the gut must also be considered. Compared with studies …

Su1800 Advanced Hepatic Fibrosis Is Associated With Increased Small Intestinal Permeability: A Novel Evaluation Incorporating a Plasma-Based Assay and Transient Elastography

ity between studies was assessed using the Cochranes Q and I2 statistics. Publication bias was evaluated by visual inspection of funnel plots. All analyses were done using Meta-Disc 1.4 and REVMAN 5.1. Results: Thirteen studies were included in the analysis: 10 for APRI (N=3,743) and 3 for TE (N=1,517). The AUCs for TE and APRI were 0.85 (95% CI 0.82-0.88) and 0.82 (95% CI 0.78-0.86) respectively. Table 1 summarizes the diagnostic performance of TE and APRI. In our subgroup analysis, significant misclassification of advanced (as significant) fibrosis by TE was more common among patients with steatosis than those without (25 vs 5%, p=0.01). APRI was accurate in diagnosis of F4 (AUC .0.80) but not for diagnosing ≥F2 and ≥F3 (AUC,0.80). APRI had lower diagnostic accuracy in the subgroup of patients with CD4 count , 250 cell/mm3 (0.64 vs 0.86, p=0.05). There was no evidence of publication bias in these analyses. Conclusion: This study shows that both TE and APRI can accurately diagnose cirrhosis in HIV-HCV co-infected patients. However, they are inaccurate for the diagnosis of significant and advanced fibrosis. The modest sensitivity and high specificity implies that both TE and APRI are better at excluding than predicting fibrosis. Moreover, the diagnostic accuracy of TE is affected by steatosis while accuracy of APRI may be affected by CD4 count. Table 1: Summary Diagnostic performance values for prediction of F2-F4 fibrosis