Chromoendoscopy Is More Effective Than Standard Colonoscopy in Detecting Dysplasia During Long-term Surveillance of Patients With Colitis.

BACKGROUND & AIMS: Patients with colitis have an increased risk of colorectal cancer, compared with persons without colitis. Many studies have shown chromoendoscopy (CE) to be superior to standard methods of detecting dysplasia in patients with colitis at index examination. We performed a prospective, longitudinal study to compare standard colonoscopy vs CE in detecting dysplasia in patients with inflammatory bowel diseases in a surveillance program. METHODS: We analyzed data from 68 patients (44 men, 24 women) diagnosed with ulcerative colitis (n = 55) or Crohn's disease (n = 13) at Mount Sinai Medical Center from September 2005 through October 2011. The patients were followed from June 2006 through October 2011 (median, 27.8 months); each patient was analyzed by random biopsy, targeted white light examination (WLE), and CE. Specimens were reviewed by a single blinded pathologist. The 3 methods were compared by using the generalized estimating equations method, and the odds ratios (ORs) for detection of dysplasia were calculated (primary outcome). Time to colectomy was analyzed by using the Cox model. RESULTS: In the 208 examinations conducted, 44 dysplastic lesions were identified in 24 patients; 6 were detected by random biopsy, 11 by WLE, and 27 by CE. Ten patients were referred for colectomy, and no carcinomas were found. At any time during the study period, CE (OR, 5.4; 95% confidence interval [CI], 2.9-9.9) and targeted WLE (OR, 2.3; 95% CI, 1.0-5.3) were more likely than random biopsy analysis to detect dysplasia. CE was superior to WLE (OR, 2.4; 95% CI, 1.4-4.0). Patients identified as positive for dysplasia were more likely to need colectomy (hazard ratio, 12.1; 95% CI, 3.2-46.2). CONCLUSIONS: In a prospective study of 68 patients with inflammatory bowel diseases, CE was superior to random biopsy or WLE analyses in detecting dysplasia in patients with colitis during an almost 28-month period. A negative result from CE examination was the best indicator of a dysplasia-free outcome, whereas a positive result was associated with earlier referral for colectomy.

Chromoendoscopy-targeted biopsies are superior to standard colonoscopic surveillance for detecting dysplasia in inflammatory bowel disease patients: a prospective endoscopic trial.

OBJECTIVES: Patients with extensive, longstanding chronic ulcerative or Crohn's colitis face greater risks of developing colorectal cancer. Current standard surveillance relies on detecting dysplasia using random sampling at colonoscopy but may fail to detect dysplasia in many patients. Dye spraying techniques have been reported to aid in detecting otherwise subtle mucosal abnormalities in the setting of colitis. We prospectively compared dye-spray technique using methylene blue to standard colonoscopic surveillance in detecting dysplasia. METHODS: One hundred fifteen patients were referred to the Chromoendoscopy Study Group and prospectively screened for the study. One hundred two (64 M, 38 F) (79 UC 23 CC) patients meeting the inclusion criteria were enrolled. Following a standard bowel preparation, each patient was examined using standard office endoscopic equipment by three methods: (a) standard surveillance colonoscopy with four random biopsies every 10 cm (for a total of at least 32 samples); (b) a targeted biopsy protocol; and finally (c) methylene blue (0.01%) dye spray was segmentally applied throughout the colon and any pit-pattern abnormality or lesion rendered visible by the dye spray was targeted and biopsied. Each patient had a single examination, which included two passes of the colonoscope. Specimens were reviewed in a blinded fashion by a single gastrointestinal pathologist. The three methods were then compared with each patient serving as his or her own control. RESULTS: Targeted biopsies with dye spray revealed significantly more dysplasia (16 patients with low grade and 1 patient with high grade) than random biopsies (3 patients with low-grade dysplasia) (P= 0.001) and more than targeted nondye spray (8 patients with low-grade and 1 patient with high-grade dysplasia) (P= 0.057). Targeted biopsies with and without dye spray detected dysplasia in 20 patients compared with 3 using Method (a) (P= 0.0002, two-tailed exact McNemar's Test). There were no adverse events. CONCLUSIONS: Colonoscopic surveillance of chronic colitis patients using methylene blue dye-spray targeted biopsies results in improved dysplasia yield compared to conventional random and targeted biopsy methods. Accordingly, this technique warrants incorporation into clinical practice in this setting and consideration as a standard of care for these patients. The value of multiple random biopsies as a surveillance technique should be revisited.

Genetic variance contributes to ingestive processes: a survey of 2-deoxy-D-glucose-induced feeding in eleven inbred mouse strains.

The feeding response following administration of the anti-metabolic glucose analogue, 2-deoxy-d-glucose (2DG), is conceptualized as an experimental model of glucoprivation, which may contribute to the understanding of inter-individual differences in glucose and carbohydrate intake and, ultimately, obesity. Although variation in the intake of several nutrients as well as food and water are known to be associated with genetic variation, it is not known whether 2DG-induced feeding is similarly genotype dependent. The present study therefore examined 2DG-induced feeding in mice of 11 inbred (A/J, AKR/J, BALB/cJ, CBA/J, C3H/HeJ, C57BL6/J, C57BL10/J, DBA/2J, SJL/J, SWR/J, 129P3/J) and one outbred (CD-1) strains across a wide range of previously determined effective 2-DG doses (200, 400, 600, 800 mg/kg) and test times (1-4 h). Orderly dose-dependent increases in 2DG-induced feeding occurred after all four doses in outbred CD-1 and inbred DBA/2J mice, across the three highest doses for BALB/cJ, SJL/J and 129P3/J mice, and across the two highest doses for CBA/J and AKR/J mice. Limited instances of 2DG-induced feeding were noted only at the highest dose in A/J and C3H/HeJ mice, or at a moderate dose in C57BL/6J mice. Further, the full 2DG dose range failed to alter food intake in C57BL/10J mice, and produced significant reductions in food intake in SWR/J mice. Food intake after 2DG doses of 200-600 mg/kg, but not 800 mg/kg, displayed significant cross-correlation, suggesting that large 2DG doses may recruit non-specific effects upon food intake. There was no correlation between food intake in the absence (vehicle baseline) of and presence of 2DG, suggesting that the regulation of glucose intake in non-challenged mice does not predict subsequent responses to glucoprivic challenge. The data demonstrate genotype-dependent variability in this glucoprivic response, and may provide the basis for the subsequent identification of trait-relevant genes.

Reciprocal opioid-opioid interactions between the ventral tegmental area and nucleus accumbens regions in mediating mu agonist-induced feeding in rats.

Feeding elicited by the mu-selective agonist, [D-Ala2, M-Phe4, Gly-ol5]-encephalin administered into the nucleus accumbens is blocked by accumbal pre-treatment with mu, delta1, delta2 and kappa, but not mu1 opioid antagonists. Correspondingly, mu-agonist-induced feeding elicited from the ventral tegmental area is blocked by ventral tegmental area pre-treatment with mu and kappa, but not delta opioid antagonists. A bi-directional opioid-opioid feeding interaction has been firmly established such that mu-agonist-induced feeding elicited from the ventral tegmental area is blocked by accumbal naltrexone, and that accumbal mu-agonist-induced feeding is blocked by naltrexone pre-treatment in the ventral tegmental area. To determine which opioid receptor subtypes mediate the regional bi-directional opioid-opioid feeding interactions between these two sites, the present study examined the dose-dependent ability of either general (naltrexone), mu (beta-funaltrexamine), kappa (nor-binaltorphamine) or delta (naltrindole) opioid antagonists administered into one site to block mu-agonist-induced feeding elicited from the other site. General, mu and kappa, but not delta opioid receptor antagonist pre-treatment in the ventral tegmental area dose-dependently reduced mu-agonist-induced feeding elicited from the nucleus accumbens. General, mu and delta, and to a lesser degree kappa, opioid receptor antagonist pre-treatment in the nucleus accumbens dose-dependently reduced mu-agonist-induced feeding elicited from the ventral tegmental area. Thus, multiple, but different opioid receptor subtypes are involved in mediating opioid-opioid feeding interactions between the nucleus accumbens and ventral tegmental area regions.

Opioid receptor subtype antagonists differentially alter GABA agonist-induced feeding elicited from either the nucleus accumbens shell or ventral tegmental area regions in rats.

Food intake is significantly increased by administration of either GABAA (e.g., muscimol) or GABAB (e.g., baclofen) agonists into either the shell region of the nucleus accumbens (NAC) or the ventral tegmental area (VTA); these responses are selectively blocked by pretreatment with corresponding GABAA and GABAB antagonists. Previous studies found that a single dose (5 microg) of the general opioid antagonist, naltrexone reduced feeding elicited by muscimol, but not baclofen in the NAC shell, and reduced feeding elicited by baclofen, but not muscimol in the VTA. The present study compared feeding responses elicited by either muscimol or baclofen in either the VTA and NAC shell following pretreatment with equimolar doses of selective mu (0.4, 4 microg), delta (0.4, 4 microg), or kappa (0.6, 6 microg) opioid receptor subtype antagonists. Muscimol (25 ng) and baclofen (200 microg) each significantly and equi-effectively increased food intake over 4 h following VTA or NAC shell microinjections. Muscimol-induced feeding elicited from the VTA was significantly enhanced by mu or delta antagonists, and was significantly reduced by kappa antagonists. Baclofen-induced feeding elicited from the VTA was significantly reduced by mu or kappa, but not delta antagonists. Muscimol-induced feeding elicited from the NAC was significantly reduced by either mu, kappa or delta antagonists. Baclofen-induced feeding elicited from the NAC was significantly reduced by kappa or delta, but not mu antagonists. These data indicate differential opioid receptor subtype antagonist-induced mediation of GABA receptor subtype agonist-induced feeding elicited from the VTA and NAC shell. This is consistent with previously demonstrated differential GABA receptor subtype antagonist-induced mediation of opioid-induced feeding elicited from these same sites. Thus, functional relationships exist for the elaborate anatomical and physiological interactions between these two neurochemical systems in the VTA and NAC shell.