Functional Bowel Disease.

Abstract

Introduction: Combination of Rome III criteria have a moderate accuracy for diagnosis of Irritable bowel syndrome (IBS). Colonoscopies are performed to rule out other etiologies, and >50% are normal being considered as a “functional disease”. It has been described and impaired intestinal barrier function with mucosal inflammation in the small bowel of this patients, and recent reports evidence a possible organic disease. However, this fact has not been completely evaluated. Aim: to determine utility of Confocal Laser Endomicroscopy (p-CLE) identifying colorectal mucosa micro-inflammation in patients with IBS. Methods: Prospective, controlled, non-randomized and simple blind study (Jan-2016/Mar-2017), including patients with IBS according to Roma III criteria (IBS group), and healthy patients (control group). Exclusion criteria: patients receiving NSAIDs, corticosteroids or antibiotics, heart, kidney, liver or severe metabolic disease, IBD, bacterial overgrowth, gastrointestinal bleeding, history of colitis, colonic obstruction, colectomy, allergy to fluorescein, pregnancy and poor bowel preparation (Boston Scale<6). Both groups underwent colonoscopy using p-CLE with target-biopsy of each colorectal section. Altered crypt architecture, epithelial gaps with fluorescein leaks and dilated and prominent branching vessels were the considered p-CLE criterion for inflammation. Following Geboes Scale, biopsies where evaluated by an only pathologist blinded to endoscopic findings. Overall diagnostic accuracy was defined by sensitivity, specificity, PPV, NPV, observed and inter-rater agreement. Results: A total of 444 biopsies (74 patients) were included (mean age 53.1 [25-90] yo, 64.9% women). Normal colonoscopy was observed in all cases. There were an increased number of inflammatory lesions at p-CLE in IBS group (65.8%) compared with controls (23.4%) (OR 6.28; 4.14 - 9.52; P<0.01) (table 1). Goebes' grade >0 was more frequently in IBS group (60.8 vs. 27.5%; P<0.01). p-CLE for inflammatory findings in IBS, considering target biopsy as gold standard, reached a sensitivity, specificity, PPV, NPV, observed and inter-rater agreement of 86.7, 88.7, 85.9, 89.4, 87.8 and 75.4%. Conclusion: p-CLE proved to be a reliable method for detecting colorectal mucosa micro-inflammation in patients with IBS, showing that patients with IBS have 6 times more prevalence of mucosal colorectal microinflammatory than healthy patients.Inflammatory lesions at p-CLE, n (%)