Alterations of gut microbiome following gastrointestinal surgical procedures and their potential complications

Intestinal microorganisms play a crucial role in shaping the host immunity and maintaining homeostasis. Nevertheless, alterations in gut bacterial composition may occur and these alterations have been linked with the pathogenesis of several diseases. In surgical practice, studies revealed that the microbiome of patients undergoing surgery changes and several post-operative complications seem to be associated with the gut microbiota composition. In this review, we aim to provide an overview of gut microbiota (GM) in surgical disease. We refer to several studies which describe alterations of GM in patients undergoing different types of surgery, we focus on the impacts of peri-operative interventions on GM and the role of GM in development of post-operative complications, such as anastomotic leak. The review aims to enhance comprehension regarding the correlation between GM and surgical procedures based in the current knowledge. However, preoperative and postoperative synthesis of GM needs to be further examined in future studies, so that GM-targeted measures could be assessed and the different surgery complications could be reduced

Quality control in upper gastrointestinal endoscopy: detection rates of gastric cancer in Oxford 2005-2008.

BACKGROUND: Gastric cancer (GC) represents the sum of advanced gastric cancer (AGC) and early gastric cancer (EGC). Endoscopy (with biopsies) is the gold standard for detection of GC, but a false-negative rate of up to 19% is reported. AIM: To determine whether patients with GC had had an oesophagogastroduodenoscopy (OGD) in the year preceding diagnosis that might reasonably have been expected to detect the cancer, as a measure of quality assurance of endoscopic practice. METHODS: Patients with histologically proven GC were identified from pathology records. Endoscopy reports and case notes were examined to identify any OGD before diagnosis, the interval and endoscopic findings. A false-negative OGD was defined as one where GC was neither suspected nor shown at pathology, but where a diagnosis of GC was made within 12 months. RESULTS: Between January 2005 and February 2008, 9764 OGDs were performed. GC was diagnosed in 74 patients (male/female ratio 2.89; median age 76, range 38-95). Nine (12%) patients had EGC. There were no differences in age, sex or symptoms between the EGC and AGC group. Sixty-eight of the 74 patients with GC (92%) presented with alarm symptoms. Ten of the 74 had had an OGD within 12 months before definitive diagnosis; all these were planned because of suspicious lesions. Significantly fewer biopsies were performed at OGDs preceding definitive diagnosis (median 2 (0-10) vs 6 (2-12); p=0.002). CONCLUSION: False-negative rates of 0% (within 12 months) and 8% (within 3 years) for diagnosis of GC are reassuring, but an inadequate number of biopsies compromises the quality assurance of endoscopy. GC presents without alarm symptoms in <10%

Cytokine receptor profiling in human colonic subepithelial myofibroblasts: A differential effect of Th polarization-associated cytokines in intestinal fibrosis

Background: Colonic subepithelial myofibroblasts (cSEMFs) are mesenchymal cells with a pivotal role in the pathophysiology of Crohn's disease (CD) fibrosis. Here, we demonstrate for the first time a complete expression mapping of cytokine receptors, implicated in inflammatory bowel diseases, in primary human cSEMFs and how pro-inflammatory cytokines regulate this expression. Furthermore, we show the effect of Th1-, Th2-, Th17- and Treg-related cytokines on a fibrosis-related phenotype of cSEMFs. Methods: Colonic subepithelial myofibroblasts were isolated from healthy individuals' colonic biopsies. Interleukin (IL)-1α- and/or tumor necrosis factor (TNF)-α-induced mRNA and protein expression of cytokine receptors was assayed by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunofluorescence, respectively. Th-related cytokine effects on mRNA and protein profibrotic factor expression were analyzed by qRT-PCR and/or colorimetric assays and on the wound-healing capacity of cSEMFs by scratch test. Results: In cSEMFs, we observed basal cytokine receptor expression, which was modified by IL-1α and TNF-α. Th1-related cytokines upregulated tissue factor (TF), collagen, fibronectin and matrix metalloproteinase (MMP)-1 and downregulated α-smooth muscle actin (α-SMA), MMP-9, and wound healing rate. Th2-related cytokines upregulated collagen, TF, α-SMA, MMP-1, and wound healing rate and downregulated fibronectin and MMP-9. IL-17 and IL-23 upregulated fibronectin, and IL-22 downregulated TF. IL-17 and IL-22 decreased wound healing rate. Similar to TGF-β, IL-23 upregulated MMP-1, tissue inhibitor of metalloproteinases-1, collagen expression, and wound healing rates. Conclusions: Our results suggest that cSEMFs have a central role in inflammation and fibrosis, as they express a great variety of Th-related cytokine receptors, making them responsive to pro-inflammatory cytokines, abundant in the inflamed mucosa of CD patients. © 2018 Crohn's & Colitis Foundation. Published by Oxford University Press. All rights reserved