Increased risk for persistent intestinal metaplasia in patients with Barrett's esophagus and uncontrolled reflux exposure before radiofrequency ablation

BACKGROUND & AIMS

Radiofrequency ablation (RFA) is a safe alternative to esophagectomy for patients with dysplastic Barrett's esophagus (BE). Although some studies have indicated that RFA is effective at eradicating dysplasia, most have found that RFA is not as effective in eradicating intestinal metaplasia. We investigated whether uncontrolled reflux is associated with persistent intestinal metaplasia after RFA.

METHODS

Thirty-seven patients with BE underwent RFA, high-resolution manometry, and 24-hour impedance-pH testing; they received proton pump inhibitors twice daily. Patients returned every 2 months for repeat treatment or standard surveillance. Patients were classified as complete responders (CRs) if all intestinal metaplasia was eradicated in fewer than 3 ablation sessions. We analyzed clinical parameters to identify factors associated with a CR or incomplete responder (ICR).

RESULTS

Among the 37 patients, 22 had a CR and 15 had an ICR. Mann-Whitney U tests revealed that length of BE, size of hiatal hernia, and frequency of reflux, but not acid reflux, differed between CRs and ICRs. CRs had fewer weakly acidic events than ICRs (29.5 vs 52; P < .05) and total reflux events (33.5 vs 60; P < .05), and a trend toward fewer weakly alkaline events (1.0 vs 5.0; P = .06). No other clinical or manometric features differed between groups.

CONCLUSIONS

Uncontrolled, predominantly weakly acidic reflux despite twice-daily proton pump inhibitor therapy before RFA increases the incidence of persistent intestinal metaplasia after ablation in patients with BE. Length of BE and size of hiatal hernia also were associated with persistent intestinal metaplasia after RFA.

Pancreatic Adenocarcinoma, version 2.2012: featured updates to the NCCN Guidelines

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Pancreatic Adenocarcinoma discuss the workup and management of tumors of the exocrine pancreas. These NCCN Guidelines Insights provide a summary and explanation of major changes to the 2012 NCCN Guidelines for Pancreatic Adenocarcinoma. The panel made 3 significant updates to the guidelines: 1) more detail was added regarding multiphase CT techniques for diagnosis and staging of pancreatic cancer, and pancreas protocol MRI was added as an emerging alternative to CT; 2) the use of a fluoropyrimidine plus oxaliplatin (e.g., 5-FU/leucovorin/oxaliplatin or capecitabine/oxaliplatin) was added as an acceptable chemotherapy combination for patients with advanced or metastatic disease and good performance status as a category 2B recommendation; and 3) the panel developed new recommendations concerning surgical technique and pathologic analysis and reporting.

Radiofrequency ablation for dysplasia in Barrett's esophagus restores β-catenin activation within esophageal progenitor cells

BACKGROUND AND AIMS

Endoscopic therapies for Barrett's esophagus (BE) associated dysplasia, particularly radiofrequency ablation (RFA), are popular alternatives to surgery. The effect of such therapies on dysplastic stem/progenitor cells (SPC) is unknown. Recent studies suggest that AKT phosphorylation of β-Catenin occurs in SPCs and may be a marker of activated SPCs. We evaluate the effect of RFA in restoring AKT-mediated β-Catenin signaling in regenerative epithelium.

METHODS

Biopsies were taken from squamous, non-dysplastic BE, dysplastic BE and esophageal adenocarcinoma (EAC). Also, post-RFA, biopsies of endoscopically normal appearing neosquamous epithelium were taken at 3, 6, and 12 months after successful RFA. Immunohistochemistry and Western blot analysis was performed for Pβ-Catenin(552) (Akt-mediated phosphorylation of β-Catenin), Ki-67 and p53.

RESULTS

There was no difference in Pβ-Catenin552 in squamous, GERD, small bowel and non-dysplastic BE. There was a fivefold increase in Pβ-Catenin(552) in dysplasia and EAC compared to non-dysplastic BE (P < 0.05). Also, there was a persistent threefold increase in Pβ-Catenin(552) in neosquamous epithelium 3 months after RFA compared to native squamous epithelium (P < 0.05) that correlated with increased Ki-67. Six months after RFA, Pβ-Catenin(552) and Ki-67 are similar to native squamous epithelium.

CONCLUSIONS

Enhanced AKT-mediated β-Catenin activation is seen in BE-associated carcinogenesis. Three months after RFA, squamous epithelial growth from SPC populations exhibited increased levels of Pβ-Catenin(552). This epithelial response becomes quiescent at 6 months after RFA. These data suggest that elevated Pβ-Catenin(552) after RFA denotes a repair response in the neosquamous epithelium 3 months post-RFA.

Barrett's esophagus: treatments of adenocarcinomas I

The following on the treatments of adenocarcinomas in Barrett's esophagus contains commentaries on endo mucosal resection; choice between other ablative therapies; the remaining genetic abnormalities following stepwise endoscopic mucosal resection and possible recurrences; the Fotelo-Fotesi PDT; the CT TNM classification of early stages of Barrett's carcinoma; the indications of lymphadenectomy in intramucosal cancer; the differences in lymph node yield in transthoracic versus transhiatal dissection; video-assisted lymphadenectomy; and the importance of the length of proximal esophageal resectipon; and indications of sentinel node dissection.

Diagnostic yield of a novel jumbo biopsy "unroofing" technique for tissue acquisition of gastric submucosal masses

BACKGROUND AND STUDY AIMS

Adequate tissue acquisition for the diagnosis of gastric submucosal masses (GSMs) has been challen ging for gastroenterologists. The use of standard biopsy forceps generally recovers non-diagnostic overlying mucosa. Endoscopic ultrasound (EUS) with fine-needle aspiration (FNA) provides a significant improvement, but is often still inadequate for diagnosis. The aim of the current study was to assess the efficacy of a novel jumbo biopsy unroofing technique (JUT) for tissue acquisition in GSM.

PATIENTS AND METHODS

This prospective study recruited patients who were referred for EUS for the evaluation of GSM between 2006 and 2009. All patients underwent EUS with FNA when feasible followed by JUT. The primary outcome was diagnostic yield of JUT.

RESULTS

A total of 93 patients were enrolled, 72 of whom were included in the investigation; 16 patients were excluded with no evidence of a submucosal mass or extrinsic compression, and five patients were further excluded by pathology confirming mucosal lesions. Of the 72 jumbo biopsies 66 (92%) provided diagnostic tissue without significant complications and 42 (58%) had lesions amenable to FNA. Although 34 of the 42 lesions were deemed adequate at the time of on-site cytological evaluation, only 28 (67%) provided sufficient tissue for final diagnosis. More importantly, only 37/72 (52%) of all patients had lesions that required any further intervention.

CONCLUSIONS

Utilization of JUT is safe and effective for diagnosis of GSM. The data suggest that the jumbo biopsy unroofing technique should be considered as an initial diagnostic strategy for GSMs found during upper endoscopy.

Barrett's esophagus: endoscopic treatments II

The following on endoscopic treatments of Barrett's esophagus includes commentaries on animal experiments on cryotherapy; indications for cryotherapy, choice of dosimetry, number of sessions, and role in Barrett's esophagus and adenocarcinoma; recent technical developments of RFA technology and long-term effects; the comparative effects of diverse ablation procedures and the rate of recurrence following treatment; and the indications for treatment of dysplasia and the role of radiofrequency ablation.

Use of a continuing medical education course to improve fellows' knowledge and skills in esophageal disorders

Advanced esophageal endoscopic procedures such as stricture dilation, hemostasis tools, and stent placement as well as high-resolution manometry (HRM) interpretation are necessary skills for gastroenterology fellows to obtain during their training. Becoming proficient in these skills may be challenging in light of higher complication rates compared with diagnostic procedures and infrequent opportunities to practice these skills. Our aim was to determine if intensive training during a continuing medical education (CME) course boosts the knowledge and skills of gastroenterology fellows in esophageal diagnostic test interpretation and performance of therapeutic procedures. This was a pretest-posttest design without a control group of a simulation-based, educational intervention in esophageal stricture balloon dilation and HRM interpretation. The participants were 24 gastroenterology fellows from 21 accredited US training programs. This was an intensive CME course held in Las Vegas, Nevada from August 7 to August 9, 2009. The research procedure had two phases. First, the subjects were measured at baseline (pretest) for their knowledge and procedural skill. Second, the fellows received 6 hours of education sessions featuring didactic content, instruction in HRM indications and interpretation, and deliberate practice using an esophageal stricture dilation model. After the intervention, all of the fellows were retested (posttest). A 17-item checklist was developed for the esophageal balloon dilation procedure using relevant sources, expert opinion, and rigorous step-by-step procedures. Nineteen representative HRM swallow studies were obtained from Northwestern's motility lab and formed the pretest and posttest in HRM interpretation. Mean scores on the dilation checklist improved 81% from 39.4% (standard deviation [SD]= 33.4%) at pretest to 71.3% (SD = 29.5%) after simulation training (P < 0.001). HRM mean examination scores increased from 27.2% (SD = 16.4%) to 46.5% (SD = 15.8%), representing a 71% improvement (P < 0.001). Pearson's correlations indicated there was no correlation between pretest performance, medical knowledge measured by United States Medical Licensing Examination examinations, prior clinical experience, or procedural self-confidence and posttest performance of esophageal dilation or HRM interpretation. The education program was rated highly. This study demonstrated that a CME course significantly enhanced the technical skills and knowledge of gastroenterology fellows in esophageal balloon dilation and HRM interpretation. CME courses such as this may be a valuable adjunct to standard fellowship training in gastroenterology.

Nutrition support in the critically ill: a physician survey

BACKGROUND

Current clinical practice guidelines delineate optimal nutrition management in the intensive care unit (ICU) patient. In light of these existing data, the authors identify current physician perceptions of nutrition in critical illness, preferences relating to initiation of feeding, and management practices specific to nutrition after initiation of feeding in the ICU patient.

METHODS

The authors electronically distributed a 12-question survey to attending physicians, fellows, and residents who routinely admit patients to medical and surgical ICUs.

RESULTS

On a scale ranging from 1 to 5 (1 = low, 5 = high), the attending physician's mean rating for importance of nutrition in the ICU was 4.60, the rating for comfort level with the nutrition support at the authors' institution was 3.70, and the rating for the physician's own understanding of nutrition support in critically ill patients was 3.33. Attending physicians, fellows, and residents reported waiting an average of 2.43, 1.79, and 2.63 days, respectively, before addressing nutrition status in an ICU patient. Fifty-two percent of attending physicians chose parenteral nutrition as the preferred route of nutrition support in a patient with necrotizing pancreatitis. If a patient experiences enteral feeding intolerance, physicians most commonly would stop tube feeds. There was no significant difference in responses to any of the survey questions between attending physicians, fellows, and residents.

CONCLUSIONS

This study demonstrates a substantial discordance in physician perceptions and practice patterns regarding initiation and management of nutrition in ICU patients, indicating an urgent need for nutrition-related education at all levels of training.

Dysbiosis in pouchitis: evidence of unique microfloral patterns in pouch inflammation

BACKGROUND & AIMS

Pouch inflammation after surgery for ulcerative colitis can significantly alter quality of life and thus ideally should be prevented. Dysbiosis or altered microflora is suspected to be the key pathogenic factor for pouchitis. However, dysbiosis in pouchitis has not been characterized carefully because of a lack of available sensitive microbiological technology suitable for in vivo studies in human beings. Thus, the aims of our study were as follows: (1) to show the use of the length heterogeneity polymerase chain reaction (LH-PCR) technique for studying microflora in human beings, and (2) to use the technique to characterize the microfloral patterns in the ileal pouch of patients with pouchitis.

METHODS

Microfloral patterns initially were assessed using a 16S ribosomal RNA technique (LH-PCR) to determine the qualitative changes in the luminal and mucosal intestinal flora. We subsequently cloned and sequenced the LH-PCR amplification products from the community 16S ribosomal RNA found in patients with pouchitis and in control pouch to identify the microbial species involved in pouchitis.

RESULTS

We have shown unique microfloral patterns in pouchitis. Through cloning and sequencing of the LH-PCR amplicons, we have shown the persistence of Fusobacter and Enteric species associated with the disease state and the absence of specific bacteria such as Streptococcus species in the inflamed pouch.

CONCLUSIONS

We have shown that the LH-PCR technique is suitable for studying microflora in human beings. By using this technique and the clone sequences, we have shown dysbiosis in the microbial biofilm adherent to the mucosa in pouchitis. Our data provide direct evidence of the role of bacteria in the pathogenesis of pouchitis.

Increases in free radicals and cytoskeletal protein oxidation and nitration in the colon of patients with inflammatory bowel disease

BACKGROUND

Overproduction of colonic oxidants contributes to mucosal injury in inflammatory bowel disease (IBD) but the mechanisms are unclear. Our recent findings using monolayers of intestinal cells suggest that the mechanism could be oxidant induced damage to cytoskeletal proteins. However, oxidants and oxidative damage have not been well characterised in IBD mucosa.

AIMS

To determine whether there are increases in oxidants and in tissue and cytoskeletal protein oxidation in IBD mucosa.

METHODS

We measured nitric oxide (NO) and markers of oxidative injury (carbonylation and nitrotyrosination) to tissue and cytoskeletal proteins in colonic mucosa from IBD patients (ulcerative colitis, Crohn's disease, specific colitis) and controls. Outcomes were correlated with IBD severity score.

RESULTS

Inflamed mucosa showed the greatest increases in oxidants and oxidative damage. Smaller but still significant increases were seen in normal appearing mucosa of patients with active and inactive IBD. Tissue NO levels correlated with oxidative damage. Actin was markedly (>50%) carbonylated and nitrated in inflamed tissues of active IBD, less so in normal appearing tissues. Tubulin carbonylation occurred in parallel; tubulin nitration was not observed. NO and all measures of oxidative damage in tissue and cytoskeletal proteins in the mucosa correlated with IBD severity. Disruption of the actin cytoarchitecture was primarily within the epithelial cells and paracellular area.

CONCLUSIONS

Oxidant levels increase in IBD along with oxidation of tissue and cytoskeletal proteins. Oxidative injury correlated with disease severity but is also present in substantial amounts in normal appearing mucosa of IBD patients, suggesting that oxidative injury does not necessarily lead to tissue injury and is not entirely a consequence of tissue injury. Marked actin oxidation (>50%)-which appears to result from cumulative oxidative damage-was only seen in inflamed mucosa, suggesting that oxidant induced cytoskeletal disruption is required for tissue injury, mucosal disruption, and IBD flare up.

Focal rectal capillaritis: microscopic polyangiitis presenting as painless rectal bleeding

Microscopic polyangiitis is a pauci-immune, necrotizing, small-vessel vasculitis without evidence of granulomatous inflammation. Gastrointestinal involvement is rare and is predominantly limited to abdominal pain. Until now, the gold standard for diagnosis has been an invasive lung or kidney biopsy. We report the case of a 59-year-old woman with microscopic polyangiitis presenting as painless rectal bleeding, which was diagnosed by rectal mucosal biopsy. This is the first reported case of microscopic polyangiitis with initial presentation of rectal bleeding and diagnosis made by rectal mucosal biopsy.

An audit of the utility of in-patient fecal occult blood testing

OBJECTIVES

Recent surveys of physician practice have suggested the existence of excessive, inappropriate use of the fecal occult blood test (FOBT). We studied the implementation of this test in hospitalized patients.

METHODS

We performed a retrospective chart review of 1000 randomly selected patients who had been discharged from the Medicine service at four teaching hospitals. Patient demographics, clinical presentation, presence or absence of overt GI bleeding, and use of medications that might affect the FOBT were recorded. Reviewers assessed whether patients who had FOBT would have been candidates for colon resection if asymptomatic colon cancer had been found.

RESULTS

Digital rectal examination was documented in 44.8% of patients; the findings were recorded in only 9%. A total of 421 patients had FOBT on admission, usually on stool obtained at digital rectal examination. Of the patients with a positive FOBT, 17% had active GI bleeding. Only 41.1% of patients with a positive FOBT were referred to the gastroenterology service. In 70.5% of patients, FOBT could be considered inappropriate because of factors such as age, active GI bleeding, or use of aspirin or other nonsteroidal anti-inflammatory drugs.

CONCLUSIONS

The FOBT, which is validated only for colorectal cancer screening, is often performed inappropriately in patients admitted to the hospital. This test should be restricted in hospital practice. It would be preferable to identify patients who are appropriate candidates for colorectal cancer screening at the time of hospital discharge and to advise them about the appropriate performance of the FOBT at home.

Management of paroxysmal atrioventricular nodal reentrant tachycardia in the critically ill surgical patient

OBJECTIVES

Paroxysmal atrioventricular nodal reentrant tachycardia is an infrequently encountered supraventricular arrhythmia that continues to present difficult management problems in the critically ill surgical patient. The purpose of this study was to evaluate the efficacy of a new treatment algorithm involving the sequential administration of different classes of antiarrhythmic agents until conversion to sinus rhythm was achieved.

DESIGN

Nonrandomized, consecutive, protocol-driven descriptive cohort.

SETTING

University hospital surgical and trauma intensive care unit (ICU).

PATIENTS

During an 11-month period, we prospectively evaluated all hemodynamically stable patients who sustained new-onset atrioventricular nodal reentrant tachycardia.

INTERVENTIONS

Vagal maneuver, followed by the rapid, sequential infusion of antiarrhythmic agents (i.e., adenosine, verapamil, and esmolol, respectively) until the arrhythmia was terminated.

MEASUREMENTS AND MAIN RESULTS

Twenty-seven patients (4% of all admissions) were evaluated, including 16 trauma patients (injury Severity Score of 20 +/- 8) and 11 general surgical patients (Acute Physiology and Chronic Health Evaluation II score of 17 +/- 7). Time from ICU admission to onset of atrioventricular nodal reentrant tachycardia was 4.5 +/- 5 days (median 2.5). Arrhythmia termination was achieved in all patients within minutes (mean 13 +/- 10 [SD]). Incremental sequential adenosine administration alone, however, was successful in affecting conversion to sinus rhythm in only 44% of initial episodes of atrioventricular nodal reentrant tachycardia (95% confidence interval 21% to 67%). A total of 14 (52%) patients developed 38 relapses of paroxysmal supraventricular tachycardia in the ICU after initial conversion to sinus rhythm. These relapses required additional antiarrhythmic therapy. Adenosine was only effective in 34% of the relapses (95% confidence interval 17% to 53%). Seven (50%) of these 14 patients developed multiple relapses. However, only two patients were receiving suppressive calcium-channel or beta-adrenergic receptor blockade at the time of relapse.

CONCLUSIONS

The use of a multiagent algorithm was effective for the initial conversion of new-onset atrioventricular nodal reentrant tachycardia to sinus rhythm in critically ill surgical and trauma patients. This preliminary report suggests that adenosine has marginal efficacy in the critically ill surgical or trauma patient. Given the high frequency of relapses, regardless of the agents used to achieve initial control, suppression therapy for the arrhythmia during the period of maximal cardiovascular stress is essential.