Efficacy of various endoscopic modalities in detecting dysplasia in ulcerative colitis: A systematic review and network meta-analysis.

BACKGROUND: Longstanding ulcerative colitis (UC) is associated with an increased risk of colonic neoplasia. Various endoscopic modalities, such as chromoendoscopy (CE), narrow band imaging (NBI) and random biopsy have been introduced for surveillance, however, there exists a paucity of direct comparisons between them. We aimed to conduct a network meta-analysis of randomized controlled trials (RCTs) performed for surveillance of neoplasia in UC. AIM: To provide a comparative evaluation of the efficacy of the above-mentioned various modalities. METHODS: We searched MEDLINE/PubMed, Web of Science, Embase, Google Scholar and Cochrane Central Registry through May 2016 for RCTs evaluating the efficacy of endoscopic modalities for surveillance of neoplasia in UC. The primary outcomes of interest were dysplasia (low- or high-grade) detection rates per biopsy and per patient, and dysplasia numbers per patient. Studies were simultaneously analyzed using a random-effects network meta-analysis under the Bayesian framework to identify the modality with the highest dysplasia detection rate. The best ranking probability for the dysplasia detection rate was analyzed by surface under the cumulative ranking (SUCRA) technique. RESULTS: Six prospective RCTs of a total 1038 patients were identified. We identified 4 different modalities; white light (WL) high definition (HD) or standard definition (SD), CE HD, and NBI HD. For dysplasia per biopsy, direct meta-analysis showed superiority of NBI HD over WL HD and CE HD over WL SD. Network meta-analysis demonstrated the rank order of best modality as NBI HD, CE HD, WL HD and WL SD with close SUCRA scores of the first two. For dysplasia per patient, direct meta-analyses showed equivocal results between each modality. Network meta-analysis demonstrated the rank order of best modality as WL HD, NBI HD, CE HD and WL SD with small differences of the SUCRA score among the first two. For dysplasia numbers per patient, direct meta-analysis showed superiority of CE HD over WL SD. Network meta-analysis demonstrated the rank order of best modality as WL HD, NBI HD, CE HD, and WL SD with small differences of the SUCRA score among the first three. CONCLUSION: We demonstrated that there were small differences among WL HD, NBI HD, and CE HD, while WL SD was inferior, in detecting dysplasia in UC.

Lower Endoscopic Diagnostic Yields Observed in Non-hematemesis Gastrointestinal Bleeding Patients.

BACKGROUND: Location of bleeding can present a diagnostic challenge in patients without hematemesis more so than those with hematemesis. AIM: To describe endoscopic diagnostic yields in both hematemesis and non-hematemesis gastrointestinal bleeding patient populations. METHODS: A retrospective analysis on a cohort of 343 consecutively identified gastrointestinal bleeding patients admitted to a tertiary care center emergency department with hematemesis and non-hematemesis over a 12-month period. Data obtained included presenting symptoms, diagnostic lesions, procedure types with diagnostic yields, and hours to diagnosis. RESULTS: The hematemesis group (n = 105) took on average 15.6 h to reach a diagnosis versus 30.0 h in the non-hematemesis group (n = 231), (p = 0.005). In the non-hematemesis group, the first procedure was diagnostic only 53% of the time versus 71% in the hematemesis group (p = 0.02). 25% of patients in the non-hematemesis group required multiple procedures versus 10% in the hematemesis group (p = 0.004). Diagnostic yield for a primary esophagogastroduodenoscopy was 71% for the hematemesis group versus 50% for the non-hematemesis group (p = 0.01). Primary colonoscopies were diagnostic in 54% of patients and 12.5% as a secondary procedure in the non-hematemesis group. A primary video capsule endoscopy yielded a diagnosis in 79% of non-hematemesis patients (n = 14) and had a 70% overall diagnostic rate (n = 33). CONCLUSION: Non-hematemesis gastrointestinal bleeding patients undergo multiple non-diagnostic tests and have longer times to diagnosis and then compared those with hematemesis. The high yield of video capsule endoscopy in the non-hematemesis group suggests a role for this device in this context and warrants further investigation.

Higher Thioguanine Nucleotide Metabolite Levels are Associated With Better Long-term Outcomes in Patients With Inflammatory Bowel Diseases.

GOALS: The aim of this study was to assess whether sustained 6-thioguaninenucleotide (6-TGN) levels were associated with improved long-term outcomes in patients with inflammatory bowel diseases (IBD). BACKGROUND: Cross-sectional data have shown that thiopurine metabolites are correlated with clinical efficacy in patient receiving thiopurines for IBD but the role for serial measurements through treatment course is unclear. STUDY: We conducted a retrospective cohort study including patients with IBD on thiopurine monotherapy and had serial 6-TGN levels measured. Predictive variables included demographics, disease phenotype, 6-TGN levels (nadir, median, and peak levels). The primary outcome was the development of a disease relapse. The secondary outcome was the need for IBD surgery. RESULTS: Two hundred eighteen 6-TGN samples from 87 patients were analyzed. Nadir and median 6-TGN levels were significantly higher in patients who did not relapse [185 and 233 pmol per 8×10 red blood cells (RBCs)] as compared with levels in patients who did relapse (150 and 167 pmol per 8×10 RBCs, P=0.025) but there was no significant difference in peak 6-TGN level. When adjusted for confounding factors, a nadir 6-TGN level ≥161 and a median 6-TGN level ≥264 were associated with a significant decrease in the rate of disease exacerbation (hazard ratio: 0.5; 95% confidence interval, 0.26-0.87; P=0.016 and hazard ratio: 0.4; 95% confidence interval, 0.2-0.82; P=0.14). CONCLUSIONS: Serial thiopurine metabolite level assessments and dose adjustment aiming to maintain higher 6-TGN levels may be helpful to improve long-term outcomes in patients with IBD.

Direct spectral analysis and determination of high content of carcinogenic bromine in bread using UV pulsed laser induced breakdown spectroscopy.

Laser induced breakdown spectroscopy (LIBS) was applied for the detection of carcinogenic elements like bromine in four representative brands of loaf bread samples and the measured bromine concentrations were 352, 157, 451, and 311 ppm, using Br I (827.2 nm) atomic transition line as the finger print atomic transition. Our LIBS system is equipped with a pulsed laser of wavelength 266 nm with energy 25 mJ pulse(-1), 8 ns pulse duration, 20 Hz repetition rate, and a gated ICCD camera. The LIBS system was calibrated with the standards of known concentrations in the sample (bread) matrix and such plot is linear in 20-500 ppm range. The capability of our system in terms of limit of detection and relative accuracy with respect to the standard inductively coupled plasma mass spectrometry (ICPMS) technique was evaluated and these values were 5.09 ppm and 0.01-0.05, respectively, which ensures the applicability of our system for Br trace level detection, and LIBS results are in excellent agreement with that of ICPMS results.