L. Sparano

The water immersion technique is easy to learn for routine use during EGD for duodenal villous evaluation: a single-center 2-year experience.

Goals We investigated the learning parameters of the immersion technique for the assessment of marked villous atrophy (MVA), during routine esophagogastroduodenoscopy (EGD). Background The immersion technique offers a proven possibility of enhancing the sensitivity of endoscopy in detecting duodenal villous atrophy patterns. Study Nine endoscopists with at least 2 years of experience, who had previously been trained to perform the immersion technique, searched for duodenal villi during routine EGD. In a 2-year study, duodenal villi were evaluated underwater duodenoscopy in 432 patients from whom duodenal biopsies had been, for various reasons, obtained. The endoscopic findings were compared with the histology. The learning parameters of the water immersion technique and the accuracy in detecting subjects with MVA were observed. Results A total of 28 (6.5%) patients with MVA were identified during endoscopy by the trained endoscopists. All these patients were diagnosed as being celiac patients. The sensitivity, specificity, and accuracy (positive and negative predictive values) of the immersion technique in detecting MVA patterns, irrespective of the endoscopist who performed the examination, were always 100%. Conclusions The underwater evaluation of the duodenum can be efficiently and regularly performed during routine EGD by endoscopists with 2 years of experience, after a specific, brief training period. This procedure is simple, feasible, and can accurately detect MVA patterns.

Small intestinal bacterial overgrowth and intestinal permeability

The gastrointestinal tract is characterized by selective and dynamic permeability allowing the passage of nutrients and fluids and preventing the penetration of intruders such as microorganisms, toxins and other luminal antigens. The gut barrier integrity is essential to maintain human health and homeostasis. A derangement of intestinal permeability (IP) seems to be involved in the pathogenesis of several intestinal and systemic disorders [1]. Several structures including mucous coat, secretory IgA, epithelial layer, intercellular tight junctions, gut immune system and gut microflora contribute to maintain the integrity of such barrier. Small intestinal bacterial overgrowth (SIBO) is a common clinical condition due to an increase in the level of microorganisms to >10 colony forming units/ml of intestinal aspirate and/or of colonictype bacteria within the small intestine. This abnormally high bacterial population could affect intestinal barrier through a direct bacterial injury or an immune system activation resulting in the release of several inflammatory mediators and cytokines [2]. Aim of this study was to assess IP in patients with SIBO and the effect of SIBO decontamination. Twenty patients affected by SIBO as assessed by hydrogen glucose breath test (GBT) (mean age 46.3 ± 7.8 years, M/F 9/11) and 21 controls without SIBO (mean age 45.1 ± 8.1 years, M/F 9/12) were enrolled after written informed consent. The test was considered as an indicative of SIBO when the peak, that is the increase over baseline hydrogen levels, was > 12 parts per million [3]. Exclusion criteria were all factors known to impair IP: gastrointestinal disorders and infections, use of non-steroidal antiinflammatory and immunosuppressive drugs, alcohol consumption, allergic diseases and HIV infection. Chromium ethylene-diamine-tetra-acetate (CrEDTA) absorption test was performed in all patients to assess IP. The test methodology was the same as described in a previous study by our group [4]. The 24-h urinary excretion of Cr-EDTA was expressed as a fraction of the oral administered dose and considered abnormal if ‡ 3% [4]. All patients were treated by rifaximin (Normix 200 mg tablets, Alfa-Wassermann) 1200 mg per day (2 tablets t.i.d.) for 7 days [5] and underwent GBT and Cr-EDTA absorption test 4 weeks after the end of the therapy. An IP derangement was observed in 11 out of 20 SIBO patients (55%, mean Cr-EDTA urinary excretion rate: 3.47 ± 0.30) compared to 1 out of 21 controls (4.8%, mean Cr-EDTA urinary excretion rate: 2.17 ± 0.16; p = 0.002). Among SIBO patients with deranged IP, IP normalized in 6 out of 8 successfully decontaminated (75%) compared to 2 out of 3 non-decontaminated patients (66%, p = ns). The mean Cr-EDTA urinary excretion rate significantly decreased after successful decontamination (2.28 ± 0.38 vs. 3.7 ± 0.58, ANOVA p < 0.005).

Treatment options for small intestinal bacterial overgrowth

Abstract The best therapeutic approach for patients with small bowel bacterial overgrowth is a combination of the removal of all predisposing conditions and the administration of broad-spectrum antibiotics. In the case of non-modifiable predisposing factors, patients with bacterial overgrowth need a strict follow-up after successful decontamination with antibiotics, in order to promptly assess and treat disease recurrence. Up to now, the choice of antibiotics has been primarily empiric because of the presence of several different bacterial species in the contaminating flora and the impossibility of applying in vitro susceptibility tests. Several systemic and non-absorbable antibiotic agents have been shown to be effective for decontamination of small bowel bacterial overgrowth. The best antibiotic scheme in terms of drug, dosage and duration of therapy remains, however, to be assessed. The non-absorbable agents seem to be associated with better safety and tolerability than systemic drugs. In the present paper, all available therapeutic approaches to small bowel bacterial overgrowth are reviewed.