Leonardo Frazzoni

Esophageal chemical clearance is impaired in gastro-esophageal reflux disease--a 24-h impedance-pH monitoring assessment.

Impedance‐pH monitoring allows assessment of retrograde and antegrade intra‐esophageal movement of fluids and gas. Reflux is followed by volume clearance and chemical clearance, elicited by secondary and swallow‐induced peristalsis, respectively. We aimed to assess whether chemical clearance is impaired in gastro‐esophageal reflux disease (GERD).

Clinical outcomes after endoscopic submucosal dissection for colorectal neoplasia: a systematic review and meta-analysis

BACKGROUND AND AIMS Endoscopic submucosal dissection (ESD) is an endoscopic resection technique for lesions suspicious of superficial malignancy. It is performed using an ESD knife on its own (standard technique) or by the sequential use of a knife and a snare (hybrid technique). The experience with these techniques is different in Asian and non-Asian countries. We performed a systematic review and meta-analysis of available evidence on colorectal ESD. METHODS Electronic databases were searched up to August 2016 for studies evaluating R0, en bloc resection, and adverse event rates of both techniques for the treatment of colorectal lesions. Proportions were pooled by a random effects model. RESULTS Ninety-seven studies (71 performed in Asia) evaluated the standard technique and 12 studies (7 in Asia) the hybrid technique. The R0 resection rate of the standard technique was 82.9%, and it was significantly lower in non-Asian versus Asian countries: 71.3% versus 85.6%. The en bloc resection rate was 91% and was significantly lower in non-Asian versus Asian countries (81.2% vs 93%, respectively). Surgery was needed in 1.1% of the ESD-related adverse events, with a significant difference between non-Asian and Asian countries (3.1% vs 0.8%). The R0 and en bloc resection rates with the hybrid technique were significantly lower than those achieved with the standard technique: 60.6% and 68.4%, respectively, with similar adverse event rates. CONCLUSIONS In non-Asian countries the standard ESD technique is still failing to achieve acceptable levels of performance. The hybrid technique showed low R0 resection rates and should not be considered as an adequate alternative to the standard technique.

Clinical outcomes following stent placement in refractory benign esophageal stricture: a systematic review and meta-analysis

BACKGROUND AND AIMS The management of refractory benign esophageal strictures (RBESs) is challenging. Stent placement has been proposed as a possible rescue strategy. We performed a systematic review and meta-analysis to examine the efficacy of this strategy in the long-term resolution of dysphagia. METHODS PubMed, SCOPUS, and Google Scholar were searched (up to January 2015). Studies recruiting adults with RBES treated with stent placement were eligible. The success, adverse event, and migration rates were pooled by means of a random-effect model to obtain odds with a 95 % confidence interval (CI). RESULTS Eighteen studies (444 patients) were eligible for inclusion. The pooled clinical success rate was 40.5 % (95 %CI 31.5 % - 49.5 %), yielding odds of 0.68 (95 %CI 0.46 - 0.98) with high heterogeneity (I(2) = 65.0 %). The meta-regression analysis showed stricture etiology as the only influencing factor. Treatment with self-expanding plastic (SEPSs) and metal stents (SEMSs) did not result in significantly higher success rates than treatment with biodegradable stents (BDSs) (46.2 % vs. 40.1 % vs. 32.9 %, respectively). The migration rate was 28.6 % (95 %CI 21.9 % - 37.1 %), yielding odds of 0.40 (95 %CI 0.28 - 0.59), with migration rates for SEPSs and SEMSs reported as being not significantly higher than BDSs (33.3 % vs. 31.5 % vs. 15.3 %, respectively). The adverse event rate was 20.6 % (95 %CI 15.3 % - 28.1 %), yielding odds of 0.26 (95 %CI 0.18 - 0.39) with no significant difference between stent types (19.4 % vs. 21.9 % vs. 21.9 %, respectively). CONCLUSIONS Stent placement in patients with RBES is effective in about 40 % of cases. Further studies should investigate whether the clinical success rate varies according to the stricture etiology.(PROSPERO registration number: CRD42015019017.).

The added diagnostic value of postreflux swallow-induced peristaltic wave index and nocturnal baseline impedance in refractory reflux disease studied with on-therapy impedance-pH monitoring

On‐therapy impedance‐pH monitoring in proton pump inhibitor (PPI)‐refractory gastroesophageal reflux disease (GERD) yielded conflicting results. We aimed to assess the diagnostic value of postreflux swallow‐induced peristaltic wave (PSPW) index and mean nocturnal baseline impedance (MNBI) in PPI‐refractory heartburn.

Laparoscopic fundoplication for gastroesophageal reflux disease.

Gastroesophageal reflux disease (GERD) is a condition that develops when the reflux of gastric contents into the esophagus leads to troublesome symptoms and/or complications. Heartburn is the cardinal symptom, often associated with regurgitation. In patients with endoscopy-negative heartburn refractory to proton pump inhibitor (PPI) therapy and when the diagnosis of GERD is in question, direct reflux testing by impedance-pH monitoring is warranted. Laparoscopic fundoplication is the standard surgical treatment for GERD. It is highly effective in curing GERD with a 80% success rate at 20-year follow-up. The Nissen fundoplication, consisting of a total (360°) wrap, is the most commonly performed antireflux operation. To reduce postoperative dysphagia and gas bloating, partial fundoplications are also used, including the posterior (Toupet) fundoplication, and the anterior (Dor) fundoplication. Currently, there is consensus to advise laparoscopic fundoplication in PPI-responsive GERD only for those patients who develop untoward side-effects or complications from PPI therapy. PPI resistance is the real challenge in GERD. There is consensus that carefully selected GERD patients refractory to PPI therapy are eligible for laparoscopic fundoplication, provided that objective evidence of reflux as the cause of ongoing symptoms has been obtained. For this purpose, impedance-pH monitoring is regarded as the diagnostic gold standard.

Impairment of chemical clearance is relevant to the pathogenesis of refractory reflux oesophagitis

BACKGROUND The pathophysiological mechanisms underlying proton pump inhibitor-refractory reflux oesophagitis has been scarcely studied. AIMS To assess impedance-pH parameters relevant to the pathogenesis of refractory reflux oesophagitis. METHODS Cases referred for heartburn/regurgitation refractory to high-dosage proton pump inhibitors between January 2008 and December 2012 were reviewed and subdivided into refractory oesophagitis (29 patients, 72% males, median age 50 years), healed oesophagitis (18 patients, 67% males, median age 54 years), and non-erosive reflux disease (49 patients, 53% males, median age 42 years). On-therapy impedance-pH tracings were blindly re-analysed by one observer to assess gastric and oesophageal acid exposure time and chemical clearance as expressed by the post-reflux swallow-induced peristaltic wave index. RESULTS The median gastric and oesophageal acid exposure time did not differ among the three groups (35%, 34%, 41% and 1.2%, 0.7%, 0.8%, respectively; P>0.05 for all comparisons). A normal oesophageal acid exposure time was found in two thirds of patients with refractory oesophagitis. The post-reflux swallow-induced peristaltic wave index was significantly lower in refractory oesophagitis (16%) than in healed oesophagitis (30%) and non-erosive reflux disease (29%) (P=0.003). CONCLUSIONS Refractory reflux oesophagitis is characterized by impairment of chemical clearance. Adequate acid suppression is found in the majority of patients who would likely not benefit from further proton pump inhibitor dose escalation.

Functional Heartburn Overlaps With Irritable Bowel Syndrome More Often than GERD

Objectives:We aimed to evaluate the prevalence of irritable bowel syndrome (IBS) in patients with typical reflux symptoms as distinguished into gastroesophageal reflux disease (GERD), hypersensitive esophagus (HE), and functional heartburn (FH) by means of endoscopy and multichannel intraluminal impedance (MII)-pH monitoring. The secondary aim was to detect pathophysiological and clinical differences between different sub-groups of patients with heartburn.Methods:Patients underwent a structured interview based on questionnaires for GERD, IBS, anxiety, and depression. Off-therapy upper-gastrointestinal (GI) endoscopy and 24 h MII-pH monitoring were performed in all cases. In patients with IBS, fecal calprotectin was measured and colonoscopy was scheduled for values >100 mg/kg to exclude organic disease. Multivariate logistic regression analysis was performed to identify independent risk factors for FH.Results:Of the 697 consecutive heartburn patients who entered the study, 454 (65%) had reflux-related heartburn (GERD+HE), whereas 243 (35%) had FH. IBS was found in 147/454 (33%) GERD/HE but in 187/243 (77%) FH patients (P<0.001). At multivariate analysis, IBS and anxiety were independent risk factors for FH in comparison with reflux-related heartburn (GERD+HE).Conclusions:IBS overlaps more frequently with FH than with GERD and HE, suggesting common pathways and treatment. HE showed intermediate characteristic between GERD and FH.

Neoplastic progression in short‐segment Barrett's oesophagus is associated with impairment of chemical clearance, but not inadequate acid suppression by proton pump inhibitor therapy

Pathophysiological mechanisms associated with neoplastic progression in patients with short‐segment Barretts oesophagus (SSBO), who represent the vast majority of the Barrett population, have not been defined.

Split dosing with a low-volume preparation is not inferior to split dosing with a high-volume preparation for bowel cleansing in patients with a history of colorectal resection: a randomized trial.

BACKGROUND AND STUDY AIM The study compared the efficacy of bowel cleansing using a low-volume mixed preparation (15 mg bisacodyl plus 2 L polyethylene glycol [PEG] solution) versus a standard high-volume preparation (4 L PEG) in patients with previous colorectal resection. PATIENTS AND METHODS A total of 120 patients with prior colorectal resection for cancer undergoing surveillance colonoscopy were randomized to receive either a split-dose low-volume (n = 60) or high-volume (n = 60) preparation for bowel cleansing. The quality of bowel preparation, rated according to a modified Ottawa Bowel Preparation scale (mOBPS), represented the primary outcome measure. Tolerability, safety, and lesion detection rates were secondary outcomes. RESULTS No significant difference was observed between the low-volume and high-volume preparations in achievement of adequate cleansing (i. e. mOBPS ≤ 4; low-volume vs. high-volume group, 85.0 % vs. 81.7 %, P = 0.624). The low-volume preparation showed a higher success rate for cleansing of the right colon (P = 0.025); better tolerability in terms of intake of the whole amount of the preparation (P < 0.001) was also observed. According to the logistic regression analysis, the only predictors of unsuccessful cleansing were previous left colectomy (P = 0.012) and a longer elapsed time since the intervention (P = 0.034). Lesion detection rates were comparable between the groups. No serious adverse events were reported. CONCLUSION A low-volume preparation is not inferior to a high-volume preparation for adequate bowel cleansing in patients with prior colorectal resection for cancer. If larger, multicenter, prospective studies confirm our findings, a low-volume preparation will represent a more tolerable option for such patients. TRIAL REGISTRATION NUMBER ClinicalTrial.gov identifier NCT01887158.

Postreflux swallow-induced peristaltic wave index and nocturnal baseline impedance can link PPI-responsive heartburn to reflux better than acid exposure time

Acid exposure time (AET) is considered the most useful parameter to predict response of reflux‐related heartburn to medical or surgical treatment. However, recent studies showed high rates of heartburn response to proton pump inhibitor (PPI) therapy in patients with normal AET.