Faculty Bibliography

INTRODUCTION/BACKGROUND:Chronic acalculous gallbladder disease (CAGD) falls within the spectrum of diseases associated with gallbladder dysmotility. Cholecystokinin-cholescintigraphy (CCK-CS) has been used to evaluate for CAGD, with a gallbladder ejection fraction (GBEF) of <35 % being indicative of gallbladder dysfunction. The reproduction of biliary colic upon administration of CCK has been cited as indicative of CAGD. Our purpose was to determine whether low GBEF or reproduction of pain during CCK-CS was predictor of surgical outcomes related to resolution of symptoms or as a correlate to gallbladder pathology. METHODS:A retrospective review of patients was performed to evaluate adults with a diagnosis of CAGD who underwent CCK-CS prior to surgical intervention. CPT and ICD-9 coding queries were used to identify the patient population. Patients with cholelithiasis were excluded. RESULTS:Sixty-four patients met inclusion criteria. Two patients were lost to follow-up and were excluded. During CCK-CS, 41 patients (66 %) reported symptoms similar to their presenting complaint. Twenty-one patients reported no symptoms with CCK-CS. There was no significant relationship between gallbladder pathology and either GBEF or reproduction of symptoms with CCK-CS (p = 0.14). About 81 % of patients (n = 50) had relief of symptoms following cholecystectomy. Sixty-six percentage of patients (n = 33) with long-term symptom relief after cholecystectomy had reproduction of symptoms with CCK-CS. Nineteen percentage of all patients (n = 12) had long-term symptom recurrence despite surgery. Eight of these patients (66 %) had symptom reproduction with CCK-CS. There was no significant correlation with either the GBEF or symptoms reproduction with CCK-CS as a predictor of postoperative outcome (p = 0.12). CONCLUSION/CONCLUSIONS:Provocation of pain by CCK-CS and low GBEF are unreliable predictors of postoperative relief of symptoms following cholecystectomy for biliary dyskinesia or chronic acalculous gallbladder disease.

Most mesenchymal neoplasms of the gastrointestinal tract are currently classified as gastrointestinal stromal tumors (GIST). Gastrointestinal stromal tumors are diagnosed by immunopositivity for CD117, CD34, and DOG1.1, with or without molecular analyses. According to the World Health Organization classification, the diagnosis of primary leiomyosarcomas of the gastrointestinal tract is so rare that there are no significant data on demographic, clinical, or gross features of this tumor. A comprehensive literature search was performed to identify gastrointestinal leiomyosarcomas. Searches were limited to the past 12 years because definitive tools to differentiate leiomyosarcomas from GIST were introduced in the late 1990s. Cases were included only if convincing data were presented. Six cases of esophageal leiomyosarcoma and 5 cases of gastric leiomyosarcoma were confirmed. Furthermore, 26 cases of leiomyosarcoma of the small bowel, 11 cases of the colon, and 8 cases arising in the rectum were identified. Finally, 28 cases of infantile and adolescent leiomyosarcoma were reviewed. Although survival analysis is precluded by small case numbers and limited survival data availability, the trend identifies that increased size and mitotic activity portends to a worse prognosis in small bowel leiomyosarcomas. Colonic leiomyosarcomas appear to be aggressive tumors, regardless of tumor size and mitotic activity. Rectal leiomyosarcomas present as smaller tumors with favorable prognosis. Leiomyosarcomas in post-GIST era are rare tumors of the gastrointestinal tract with distinctive clinicopathologic characteristics. Owing to different treatment options, it is necessary to accurately differentiate these from GIST, using a combination of histologic appearance, presence of smooth muscle antigens, and absence of specific GIST immunomarkers.

INTRODUCTION/BACKGROUND:Lubiprostone is approved in the United States for the treatment of chronic idiopathic constipation and constipation predominant irritable bowel syndrome (IBS-C). Lubiprostone causes secretion of fluid and electrolytes in the small bowel, through the activation of chloride channels, and thereby induces laxation and improvement of bowel functions. It is generally considered to be safe and effective. Common side effects of lubiprostone include nausea, diarrhea, abdominal pain and bloating, and the rare side effect dyspnea. Likely mechanisms for these side effects may be related to lubiprostone's primary action on small bowel secretion and the associated intestinal distension, as well as smooth muscle contraction. AREAS COVERED/METHODS:This article reviews the pharmacokinetic and safety profile of lubiprostone, with particular relevance to the two FDA-approved dosages. EXPERT OPINION/CONCLUSIONS:Lubiprostone acts topically in the gut lumen and is almost completely metabolized in the gut lumen. Lubiprostone's M3 metabolite can be detected in low concentrations in the serum and may be responsible for some of its side effects. However, the exact mechanisms by which the side effects are produced are currently unknown.

INTRODUCTION/BACKGROUND:Weight loss is a commonly used indication for colonoscopy. METHODS:This is a prospective case study of colonoscopies from 1998 to 2009. Descriptive statistics were used to evaluate age, sex, colonoscopy indications, and findings. Multiple logistic regression analysis was used to determine the odds of colorectal cancer (CRC) based on age, sex, and weight loss. RESULTS:We reviewed 6425 colonoscopies. The mean age of patients was 57.4 years (SD, ±13.5 years), and 55% of patients were women. One hundred thirty-six (2.1%) of these had unintentional weight loss; for 32 patients (0.4%), unintentional weight loss was the only indication for the procedure. CRC was diagnosed in 116 patients (1.8%), but CRC was not detected in any patients for whom unintentional weight loss as the only indication for colonoscopy. CONCLUSION/CONCLUSIONS:Based on our prospective case study, unintentional weight loss alone was not associated with CRC.

AIM/OBJECTIVE:To assess the additive effect of lubiprostone on the quality of colon preparation in diabetics given single-dosed polyethylene glycol electrolyte (PEG) for colonoscopy. METHODS:This was an investigator-initiated, single-center, single-blinded prospective trial comparing the efficacy of L + PEG to PEG alone on colon preparation quality in diabetics undergoing screening colonoscopy. The study was approved by our institution's IRB. The PEG was given as a single-dose to address patient-compliance concerns voiced by our IRB with split-dosing. All patients received only clear liquids the day prior to colonoscopy. Experimental group (Grp L) received PEG + 1 dose L 2 h prior to and 2 h after PEG completion. Control group (Grp C) received only PEG the evening prior to the colonoscopy. Patients were randomly assigned to one of the 2 groups. The endoscopist was blinded to which colon prep was given and all colonoscopies were complete. Upon colonoscopy completion, the endoscopist rated the colon prep-quality by a validated 5-point Likert scale (1-excellent to 5-inadequate). RESULTS:Sixty patients were enrolled in the study; 30 Grp L and 30 Grp C. Overall, patients were excluded due to study non-completion in 12 (41%) Grp L and 5 (17%) Grp C, P = 0.04. Average colon preparation score Grp L = 2.47 and Grp C = 3.00, P = 0.09. Although this was not statistically significant, there was a trend towards improved colon prep in Grp L. Statistical significance may have been achieved if completion rates had been similar between both study groups. CONCLUSION/CONCLUSIONS:Use of 2-L capsules with PEG resulted in a trend towards improved colon prep over PEG alone in diabetic patients when given as a single-dose regimen.

This is a commentary on the recently published meta-analysis by Wilkins et al which concluded that primary care physicians are able to provide comparable quality in performing colonoscopic colon cancer screening as gastroenterologists.

BACKGROUND:Acute non-variceal upper gastrointestinal bleeding (ANVB) or hemorrhage (used interchangeably) is an emergency. Endoscopically applied hydrogen peroxide (H2O2) has been shown to improve visualization of the ulcer base. AIMS/OBJECTIVE:To test the hypothesis that ulcer base clot clearance with 3% H2O2 improves the visualization of ANVB lesions compared to water alone. METHODS:In this single-center prospective study, 320 patients with ANVB were examined, of which 81 met the entry criteria for evaluation. All patients with ANVB underwent urgent endoscopy. Those with adherent clots on the ulcer base were sprayed with 250 ml of water, followed by up to 100 ml of 3% H2O2. The main outcome measurement was Kalloo"s Visual Scores of the ulcer base before and after water and H2O2. RESULTS:Eighty-one patients with gastric ulcers (GU; 34) and duodenal ulcers (DU; 47) met the entry criteria. The mean improvement in grade from water to H2O2 was 2.04 (95% confidence interval [CI] (1.86, 2.23)). The mean volume of H2O2 used to clear clots was higher (70 ml) in patients who were negative for both Helicobacter pylori and non-steroidal anti-inflammatory drug (NSAID) use than in those who were positive for both (31 ml) (P = 0.00). More DU patients (72%) had visible vessels than GU patients (44%) (P = 0.01). CONCLUSIONS:H2O2 improved the visualization of ulcer bases in ANVB. A smaller volume of H2O2 was required to clear clots in patients who used NSAIDs and had H. pylori infection. H2O2 identified more DU vessels. The use of H2O2 should be considered as a standard therapy in the management of clots in ANVB.