Hank S. Wang

Adenoma detection rate is necessary but insufficient for distinguishing high versus low endoscopist performance

BACKGROUND Endoscopist quality is benchmarked by the adenoma detection rate (ADR)-the proportion of cases with 1 or more adenomas removed. However, the ADR rewards the same credit for 1 versus more than 1 adenoma. OBJECTIVE We evaluated whether 2 endoscopist groups could have a similar ADR but detect significantly different total adenomas. DESIGN We retrospectively measured the ADR and multiple measures of total adenoma yield, including a metric called ADR-Plus, the mean number of incremental adenomas after the first. We plotted ADR versus ADR-Plus to create 4 adenoma detection patterns: (1) optimal (↑ADR/↑ADR-Plus); (2) one and done (↑ADR/↓ADR-Plus); (3) all or none (↓ADR/↑ADR-Plus); (4) none and done (↓ADR/↓ADR-Plus). SETTING Tertiary-care teaching hospital and 3 nonteaching facilities servicing the same patient pool. PATIENTS A total of 3318 VA patients who underwent screening between 2005 and 2009. MAIN OUTCOME MEASUREMENTS ADR, mean total adenomas detected, advanced adenomas detected, ADR-Plus. RESULTS The ADR was 28.8% and 25.7% in the teaching (n = 1218) and nonteaching groups (n = 2100), respectively (P = .052). Although ADRs were relatively similar, the teaching site achieved 23.5%, 28.7%, and 29.5% higher mean total adenomas, advanced adenomas, and ADR-Plus versus nonteaching sites (P < .001). By coupling ADR with ADR-Plus, we identified more teaching endoscopists as optimal (57.1% vs 8.3%; P = .02), and more nonteaching endoscopists in the none and done category (42% vs 0%; P = .047). LIMITATIONS External generalizability, nonrandomized study. CONCLUSION We found minimal ADR differences between the 2 endoscopist groups, but substantial differences in total adenomas; the ADR missed this difference. Coupling the ADR with other total adenoma metrics (eg, ADR-Plus) provides a more comprehensive assessment of adenoma clearance; implementing both would better distinguish high- from low-performing endoscopists.

Elevated Serum Ghrelin Exerts an Orexigenic Effect that May Maintain Body Mass Index in Patients with Metastatic Neuroendocrine Tumors

Ghrelin is a potent orexigenic peptide principally produced in the stomach by a distinct population of neuroendocrine cells in the oxyntic mucosa of the fundus. Exogenous ghrelin given as an intravenous infusion has been shown to increase caloric intake in patients with cancer cachexia. In this study, we hypothesized that elevated endogenous ghrelin, produced by increased neuroendocrine cell tumor burden, also exerts an orexigenic effect helping to maintain body mass index. To evaluate the effect of elevated endogenous ghrelin, 35 patients with neuroendocrine tumors were enrolled, assigning them to one of two groups depending on the presence of hepatic metastases. Following an overnight fast, serum was collected and sent for ghrelin measurement by an outside laboratory. The two groups were well matched for all other relevant clinical variables including subtype of tumor, primary location of tumor and tumor treatment history. Nearly all patients with hepatic metastases had elevated levels of ghrelin compared to the standard reference range given for matched controls. The presence of hepatic metastases was associated with significantly elevated ghrelin levels (p<0.05) and a greater mean body mass index. In addition, we report a positive correlation between serum ghrelin and total tumor surface area and between serum ghrelin and body mass index, suggesting that elevated endogenous ghrelin may be sufficient to overcome any partial ghrelin resistance typically seen in cancer cachexia. These results support the possibility that ghrelin is co-released from neuroendocrine tumors and exerts an orexigenic effect in these patients, helping to maintain their body mass index despite widely disseminated disease.

Management of Hepatitis B in Special Patient Populations

Hepatitis B virus is a common cause of acute liver failure. It can be especially problematic in patients coinfected with hepatitis C, hepatitis D or human immunodeficiency virus. In addition, immunosuppression-associated hepatitis B reactivation is being increasingly recognized following chemotherapy, biologic therapy, and organ transplantation. This article highlights treatment options in these special populations.

The Walkerton Outbreak Revisited at Year 8: Predictors, Prevalence, and Prognosis of Postinfectious Irritable Bowel Syndrome

Ultimately, it is clear that this study highlights the importance of quality assurance measures within colorectal cancer screening programs. There are numerous proposals for using these measures as part of health care payment reform (Am J Gastroenterol 2010;105: 1925–1933). Professional gastroenterology societies are creating benchmarking programs to allow for comparison of an endoscopist to colleagues nationwide. But will these efforts improve patient outcomes by improving endoscopist performance? After identifying an association between withdrawal time and ADR, Barclay et al demonstrated improved ADR with use of an audible timer during endoscope withdrawal and additional training in a journal club format detailing inspection techniques (Clin Gastroenterol Hepatol 2008;6:1091–1098). However, a recent study had more discouraging results with no significant ADR improvement despite planned, systematic interventions, such as feedback and financial incentives (Clin Gastroenterol Hepatol 2009;7:1335– 1340). Nevertheless, Kaminski et al have strengthened the argument for increased attention to quality measures for colonoscopy, especially the ADR. Future research studies should be designed to determine what ADR is appropriate to use as a benchmark to optimize outcomes, if ADR is truly associated with cancer incidence and mortality, and if surveillance intervals can safely be extended after high quality colonoscopy in average risk patients. Furthermore, methods to improve endoscopist performance need to be developed and tested, especially given that only 14% of endoscopists were in the high ADR group in this study.

Duodenal Bulb Mucosa with Hypertrophic Gastric Oxyntic Heterotopia in Patients with Zollinger Ellison Syndrome

Objectives. Zollinger-Ellison Syndrome (ZES) results in hypersecretion of gastric acid (via gastrinoma) leading to peptic ulcers, diarrhea, and abdominal pain. We describe the novel discovery of hypertrophic, heterotopic gastric mucosa in the proximal duodenal bulb in patients with ZES, which we hypothesize results in an increased incidence of postbulbar ulcers in patients with ZES (a mechanism previously unreported). We determined the incidence of the novel finding of duodenal gastric oxyntic hypertrophic heterotopia (GOH) in patients with ZES. Methods. Seven patients with ZES were enrolled. The diagnosis of ZES was established by hypergastrinemia, gastric acid hypersecretion, and a positive secretin test or based on biopsy specimens (evaluated via tissue staining). Basal acid output (BAO) and baseline gastrin secretion were determined by established methods. Endoscopic examinations with methylene blue staining and biopsy of the gastric and duodenal mucosa were conducted in all patients every 3–6 months for an average of 5 years. Results. The duodenal mucosa demonstrated hypertrophic GOH in 5 out of 7 patients with ZES and an intact stomach and duodenum. Biopsies from the bowel mucosa demonstrated patchy replacement of surface epithelium by gastric-type epithelium with hypertrophic oxyntic glands in the lamina propria in 5 patients. Two of the patients had no evidence of GOH in the duodenal bulb. Patients with GOH had an average serum gastrin level of 1245 pg/mL and BAO of 2.92 mEq/hr versus 724 pg/mL and 0.8 mEq/hr in patients without GOH. Conclusions. This study demonstrated the presence of duodenal mucosa with GOH in 5 out of 7 patients with ZES and an intact stomach and duodenum. The presence of hypertrophic and heterotopic gastric mucosa is proposed to result from increased gastrin levels and may contribute to the increased incidence of postbulbar ulcers in these patients.

Preventing Endoscopy Clinic No-Shows: Prospective Validation of a Predictive Overbooking Model

OBJECTIVES:Patient absenteeism for scheduled visits and procedures (“no-show”) occurs frequently in healthcare systems worldwide, resulting in treatment delays and financial loss. To address this problem, we validated a predictive overbooking system that identifies patients at high risk for missing scheduled gastrointestinal endoscopy procedures (“no-shows” and cancellations), and offers their appointments to other patients on short notice.METHODS:We prospectively tested a predictive overbooking system at a Veterans Administration outpatient endoscopy clinic over a 34-week period, alternating between traditional booking and predictive overbooking methods. For the latter, we assigned a no-show risk score to each scheduled patient, utilizing a previously developed logistic regression model built with electronic health record data. To compare booking methods, we measured service utilization—defined as the percentage of daily total clinic capacity occupied by patients—and length of clinic workday.RESULTS:Compared to typical booking, predictive overbooking resulted in nearly all appointment slots being filled—2.5 slots available during control weeks vs. 0.35 slots during intervention weeks, t(161)=4.10, P=0.0001. Service utilization increased from 86% during control weeks to 100% during intervention weeks, allowing 111 additional patients to undergo procedures. Physician and staff overages were more common during intervention weeks, but less than anticipated (workday length of 7.84 h (control) vs. 8.31 h (intervention), t(161)=2.28, P=0.02).CONCLUSIONS:Predictive overbooking may be used to maximize endoscopy scheduling. Future research should focus on adapting the model for use in primary care and specialty clinics.

Comparative Efficacy of Rabeprazole and Pantoprazole in the Control of Nocturnal Acid Output and Intragastric Acidity

BACKGROUND/AIMS Nocturnal reflux is a largely undiagnosed and unmanaged condition predisposing to multiple esophageal complications. We evaluated the effects of rabeprazole and pantoprazole on nocturnal intragastric pH and gastric acid output during Day 1 of therapy following the consumption of standard meals. METHODS The study had a double-blinded, randomized, two-way crossover design, and involved 15 patients with a history of mild reflux. Following an overnight fast, patients were given either rabeprazole (20 mg) or pantoprazole (40 mg) prior to the first of three standard Western meals. They then underwent overnight continuous intragastric pH monitoring and gastric acid output measurement. The drug effect was analyzed using a two-treatment, two-period crossover mixed model. RESULTS The percentage of time during which the mean intragastric pH was greater than 4.0 and gastric acid output was less than 2.0 was higher for oral rabeprazole (p<0.05). The inhibition of acid output was greater for rabeprazole at almost all time points. Furthermore, the mean time-matched pH values differed significantly over the first 8.3 hours (p<0.05). CONCLUSIONS On day 1, oral rabeprazole inhibited acid output to a greater extent and for a longer period than pantoprazole, and the intragastric pH was significantly higher for rabeprazole than for pantoprazole over the first 8.3 hours.

Cyto‐reduction of neuroendocrine tumours using Sandostatin LAR® in combination with Infergen®: results of a case series

Historically, limited trials evaluating biotherapy in treating metastatic neuroendocrine tumours have yielded mixed results. In this study, the efficacy of a novel combination therapy featuring long‐acting Sandostatin LAR® plus α‐interferon was evaluated. In a prospective case series, 12 patients with unresectable metastatic neuroendocrine tumours refractory to treatment initiated therapy with Infergen® and Sandostatin LAR®. Radiological response was followed serially at 3‐month intervals. A biochemical response was considered significant if marker levels decreased by ≥50% compared with baseline. Inhibition of tumour growth lasting for greater than 3 months (mean response 22.6 ± 17.7 months) was seen in eight patients. Complete tumour regression was observed in one patient, lasting for 40 months; three patients exhibited partial tumour regression (mean response 29.3 ± 24.0 months), and four patients maintained a stable tumour response (mean response 13.3 ± 9.2 months). Four patients showed no response to therapy (mean response 5.0 ± 6.0 months). All enrolled patients are alive currently. The biochemical response seen in seven patients did not correlate with the radiological response. These results suggest that the novel combination of long‐acting Sandostatin LAR® with an α‐interferon may be at least as effective as either combination therapy with short‐acting octreotide or monotherapy with Sandostatin LAR®.

Mo1030 Less Experienced Endoscopists are More Likely to Report “Sub-Optimal” Bowel Preparation Quality vs. More Experienced Endoscopists

Less Experienced Endoscopists are More Likely to Report “Sub-Optimal” Bowel Preparation Quality vs. More Experienced Endoscopists Hank S. Wang, Scott Kubomoto, Aaron Lee, Luis H. Ocampo, Michael D. Baek, Gobind N. Sharma, Jessica Liu, Rusha Modi, Nattapaun N. Thepyasuwan, Alexander Levy, Michelle Vu, Victoria Sheen, Mary A. Atia, Kamyar Shahedi, Bradley J. Snyder, Poyrung Poysophon, Brennan M. Spiegel