Douglas B. Nelson

Risk factors for severe delayed postpolypectomy bleeding

BACKGROUND AND STUDY AIMS Postpolypectomy bleeding is a rare but serious adverse event. The aim of this study was to identify factors associated with the risk of severe delayed postpolypectomy bleeding. PATIENTS AND METHODS This was a case-control study, comparing cases who developed hematochezia and required medical evaluation 6 hours to 14 days after colonoscopic polypectomy, and control patients who underwent polypectomy without delayed bleeding, and who were selected in approximately a 3 : 1 ratio. The following risk factors were specified a priori: resuming anticoagulation (within 1 week following polypectomy), aspirin use, hypertension, and polyp diameter. RESULTS Of the 4592 patients who underwent colonoscopy with polypectomy, 41 patients (0.9 %) developed delayed postpolypectomy bleeding (cases), and 132 patients were selected as controls. The mean age was 64.3 years for cases and 65.4 years for controls. Cases presented on average 6 days after polypectomy (range 1 - 14 days), and 48 % required blood transfusion (average 4.2 units, range 0 - 17). Two patients required surgery. Anticoagulation was resumed following polypectomy in 34 % of cases compared with 9 % of controls (OR 5.2; 95 % CI 2.2 - 12.5; P < 0.001). For every 1 mm increase in polyp diameter, the risk of hemorrhage increased by 9 % (OR 1.09; 95 % CI 1.0 - 1.2; P = 0.008). Hypertension (OR 1.1) and aspirin use (OR 1.1) did not increase the risk of postpolypectomy bleeding. In exploratory analysis, diabetes (OR 2.5) and coronary artery disease (OR 3.0) were associated with postpolypectomy hemorrhage, but the association was no longer statistically significant once adjusted for the use of anticoagulation. CONCLUSIONS Resuming anticoagulation following polypectomy and polyp diameter were strongly associated with increased risk of severe delayed postpolypectomy bleeding.

Plastic versus self-expanding metallic stents for malignant hilar biliary obstruction: a prospective multicenter observational cohort study.

Background There are few comparative data as to whether plastic or self-expanding metallic stents are preferable for palliating malignant hilar biliary obstruction. Methods Thirty-day outcomes of consecutive endoscopic retrograde cholangiopancreatographies performed for malignant hilar obstruction at 6 private and 5 university centers were assessed prospectively. Results Patients receiving plastic (N=28) and metallic stents (N=34) were similar except that metallic stent recipients more often had: Bismuth III or IV tumors (16/34 vs. 5/28 P=0.043), higher Charlson comorbidity scores (P=0.003), metastatic disease (P=0.006), and management at academic centers (P=0.018). The groups had similar rates of bilateral stent placement (4/28 vs. 5/34), and similar frequency of opacified but undrained segmental ducts (7/28 vs. 5/34). Adverse outcomes including cholangitis, stent occlusion, migration, perforation, and/or the need for unplanned endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography occurred in 11/28 (39.3%) patients with plastic versus 4/34 (11.8%) with metal stents (P=0.017). By logistic regression, factors associated with adverse outcomes included plastic stent placement (odds ratio 6.32; 95% confidence interval 1.23, 32.56) and serum bilirubin (1.11/mg/dL above normal: 1.01, 1.22) but not center type or Bismuth class. Conclusions Metallic stent performance was superior to plastic for hilar tumor palliation with respect to short-term outcomes, independent of disease severity, Bismuth class, or drainage quality.

Major hemorrhage from endoscopic sphincterotomy : risk factor analysis

We carried out a retrospective cohort study on all patients undergoing sphincterotomy at our institution over a 4-year period. Major hemorrhage occurred in 10 of 189 patients (5.3%). Onset was usually delayed (mean, 3.0 days; range, 0-9 days). Six potential risk factors for postsphincterotomy hemorrhage were assessed by univariate and multivariate analysis. Three factors predicted postsphincterotomy hemorrhage: hemodialysis (relative risk, 8.4; 95% confidence interval, CI, 2.7-26.4), a prothrombin time prolonged at least 2 s above control (relative risk, 7.8; 95% CI, 2.4-25.6), and endoscopically observed bleeding at the time of sphincterotomy (relative risk, 5.9; 95% CI, 1.7-20.1). Features not independently associated with hemorrhage were sphincter of Oddi dysfunction, aspirin or nonsteroidal anti-inflammatory drug (NSAID) use within 1 week prior to sphincterotomy, and sphincterotomy length. When differentiated from endoscopically observed bleeding, clinically significant hemorrhage was usually a delayed complication, primarily in patients with hemostatic defects.

Bacteremia with esophageal dilation

BACKGROUND Antibiotic prophylaxis has been recommended for selected patients undergoing esophageal stricture dilation because of a reported high rate of bacteremia. The aim of this study was to determine the rate of bacteremia after esophageal dilatation in a large series and the source of the organisms recovered. METHODS Blood cultures and oral temperatures were obtained before esophageal dilation and at 5 and 30 minutes after dilation. Dilators were cultured immediately before dilation. Procedural data collected included type of dilation, number of passes, and presence of malignancy. RESULTS Of 100 procedures in 86 patients undergoing esophageal dilation, 22 (22%) were associated with a positive post-dilation blood culture. Bacteremia was more frequent with dilation of malignant strictures compared with benign strictures (9 of 17 [52.9%] vs. 13 of 83 [15.7%], respectively, p = 0.002) and with passage of multiple dilators compared with passage of a single dilator (16 of 46 [34.8%] versus 6 of 54 [11.1%], respectively, p = 0.007). Bacterial isolates from 22 positive blood cultures matched those from a dilator in only one episode (4.5%). CONCLUSION The rate of bacteremia after esophageal dilation is 22% and is associated with dilation of malignant strictures or passage of multiple dilators. Organisms cultured from the blood are not transmitted from the dilator.

Acute GI Bleeding in the Setting of Supratherapeutic International Normalized Ratio in Patients Taking Warfarin: Endoscopic Diagnosis, Clinical Management, and Outcomes

BACKGROUND Acute GI bleeding is a life-threatening complication of warfarin therapy. Acute GI bleeding in patients with an international normalized ratio of 4.0 or greater (supratherapeutic) is often attributed to trivial mucosal lesions. The aim of the study was to determine the frequency of potentially significant lesions that would warrant endoscopy in this setting. METHODS A retrospective review was conducted of patients treated with warfarin who were admitted to a single Veterans Affairs hospital from 1996 to 2000 with acute GI bleeding. Endoscopic findings, clinical management, and outcomes are reviewed for patients with a supratherapeutic international normalized ratio (>or=4.0) and compared with patients with an international normalized ratio in the therapeutic range (2.0-3.9). RESULTS Fifty-five patients with an international normalized ratio of 4.0 or greater (mean 8.4 [3.9]) and 43 patients with an international normalized ratio between 2.0 and 3.9 (mean 2.9 [0.6]) were hospitalized with acute GI bleeding. Thirty-seven patients (67%) with a supratherapeutic international normalized ratio and GI bleeding underwent upper endoscopy. Of these, 81.1% had positive findings, 18.9% had peptic ulcer disease, and 7.2% required endoscopic treatment. Thirty-eight percent of the patients with a supratherapeutic international normalized ratio underwent lower endoscopy; of these, 57.1% had abnormal findings and 9.5% required endoscopic treatment. Four patients (7.3%) in the supratherapeutic international normalized ratio group died during the index hospitalization. When patients with GI bleeding and a therapeutic international normalized ratio were compared with those with a supratherapeutic international normalized ratio, there were no significant differences between the two groups with regard to days of hospitalization, units of blood transfused, frequency of recurrent bleeding, need for surgery, or in-hospital deaths. CONCLUSIONS The high frequency of clinically significant lesions in patients taking warfarin with an international normalized ratio in the supratherapeutic range and acute GI bleeding supports a role for endoscopic evaluation.

Should patients with anemia and low normal or normal serum ferritin undergo colonoscopy

BACKGROUND:Patients with unexplained iron deficiency anemia have a greater prevalence of colonic neoplasia, and should be evaluated for a colonoscopy. The approach to patients with anemia without iron deficiency remains unclear.OBJECTIVE:To compare the prevalence of colonic neoplasia in anemic patients with normal ferritin (>50 ng/mL), to those with ferritin ≤50 ng/mL, and nonanemic individuals.METHODS:Patients referred for colonoscopy for anemia evaluation were stratified into 3 groups: ferritin ≤50 ng/mL, 51–100 ng/mL, and >100 ng/mL. We compared these groups to each other, and to asymptomatic nonanemic individuals undergoing screening colonoscopy. The prevalence of advanced colonic neoplasia was determined for each group using existing records.RESULTS:During the study period, 414 patients who underwent colonoscopy for anemia evaluation and 323 nonanemic individuals who underwent colonoscopy for cancer screening met inclusion criteria. Study subjects were mostly men. The prevalence of advanced colonic neoplasia in subjects with ferritin 51–100 ng/mL was 7.2% (95% CI 2.4–17.9%), similar to 7.9% (95% CI 5.1–11.9%) in those with ferritin ≤50 ng/mL. The incidence of advanced colonic neoplasia in subjects with ferritin >100 ng/mL was 1.7% (95% CI 0.1–6.6%), similar to 1.2% (95% CI 0.4–3.3%) in the asymptomatic nonanemic group. After adjusting for age, patients with ferritin ≤50 ng/mL and 51–100 ng/mL were almost 5 times more likely to harbor advanced colonic neoplasia than the other groups. The addition of other laboratory parameters did not improve the predictive value of ferritin.CONCLUSION:A ferritin cutoff of 100 ng/mL can be used to determine the need for colonoscopy in men with anemia.

Dyspepsia is associated with CagA-positive Helicobacter pylori

OBJECTIVE:The role of Helicobacter pylori in nonulcer dyspepsia is controversial. Speculation has arisen that only strains of H. pylori carrying the CagA virulence factor are important in the development of dyspepsia. The objective of this study was to determine whether nonulcer dyspepsia correlated with CagA-positive H. pylori infection.METHODS:A total of 435 healthy blood donors and 102 general medicine clinic respondents completed the Bowel Disease Questionnaire and the PRIME-MD survey, a validated screen for common psychiatric disorders. Subjects were classified as cases of nonulcer dyspepsia if they reported pain in the upper abdomen more than six times in the previous year and denied a past or current history of peptic ulcer disease. Study participants were tested for IgG antibodies to H. pylori and the CagA protein.RESULTS:Clinic respondents were more likely than healthy blood donors to meet the case definition for nonulcer dyspepsia (34% vs 13%, p < 0.001), to be seropositive for H. pylori (54% vs 18%, p < 0.001), and to be CagA seropositive (41% vs 10%, p= 0.01). Logistic regression identified CagA seropositivity (p= 0.03), race (p= 0.001), and positive screens for depression (p= 0.007) or somatization (p < 0.001) as variables independently associated with nonulcer dyspepsia.CONCLUSION:Infection with a CagA-positive strain of H. pylori is associated with a clinical diagnosis of nonulcer dyspepsia. However, nonulcer dyspepsia was also strongly and independently associated with positive screens for depression or somatization disorder as well as with ethnicity. These potential sources of variance should be considered in the design of future studies evaluating nonulcer dyspepsia.

Clinical application of a new disposable lithotripter: a prospective multicenter study

BACKGROUND Mechanical lithotripsy has become a well-accepted method of bile duct stone fragmentation and removal. The Olympus lithotripter (Olympus American, Melville, NY) is the standard reusable lithotripter at the institutions that participated in this study. A disposable device with a preassembled pistol grip may perform equally well and facilitate operation. METHODS Twenty patients with bile duct stones were evaluated as part of a multicenter prospective study. Data were obtained regarding stone size and number, bile duct diameter, and configuration, ease of cannulation, basket function, stone capture and crushing success, and complications. RESULTS The maximum stone size averaged 16.5 +/- 1.2 mm (range 10 to 30 mm). Sixteen patients had multiple stones (median 5, range 2 to 12). The mean bile duct diameter was 20.5 +/- 1.5 mm (range 12 to 38 mm). Cannulation was successful in all within 5 attempts. Basket deployment failed in 1 patient because of stone size and the basket was misshapen in 14. Bile duct clearance was complete in 16 subjects (80%), incomplete in 2 patients, and failed in 2 patients. Abnormal duct configuration (sigmoid, stricture) was noted in 2 of 4 patients with failed capture and 7 of 16 patients with successful clearance. No statistically significant difference was observed between the bile duct diameter, maximum stone size, number of stones, and successful clearance. CONCLUSION The disposable lithotripter is easy to use and, compared with the published results for the reusable lithotripter, performs almost as well.

Ten-year response to stenting in a patient with primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is an idiopathic disorder characterized by inflammatory destruction of large and small bile ducts and resultant cholestatic liver disease.1 The clinical course is characterized by a gradual but progressive deterioration punctuated by remissions and exacerbations, eventually resulting in cirrhosis and liver failure.1-4 Medical treatment including antibiotics,5 corticosteroids,6 azathioprine,7 cholestyramine,8 penicillamine,9 colchicine,10,11 methotrexate,12 and ursodeoxycholic acid13 has been shown to be ineffective. Tacrolimus (FK 506) has shown some promise of short-term benefit but has not been studied in a randomized controlled trial.14 A number of different surgical treatments have been used in an attempt to reduce the frequency of attacks of cholangitis. They have generally been found to be ineffective and in addition make liver transplantation more difficult.15-17 Endoscopic treatments including sphincterotomy, dilation of strictures, placement of endoprostheses, and biliary lavage have been used.18-25 Uncontrolled studies have shown improvement after various endoscopic treatments; however, these treatments generally have a short-term effect. We present the case of a patient successfully managed by endoscopic therapy for over 10 years. From the Gastroenterology Section, VA Medical Center, University of Minnesota, Minneapolis, Minnesota. Reprint requests: Douglas Nelson, MD, Gastroenterology Section (111D), VA Medical Center, One Veterans Drive, Minneapolis, MN 44417. 37/4/86107 Ten-year response to stenting in a patient with primary sclerosing cholangitis S Silvis, D Nelson, P Meier

Effectiveness of manual cleaning and disinfection for the elimination of hepatitis C virus from GI endoscopes.

TO THE EDITOR: Dr. Longstreth’s comments and suggestions regarding the disadvantage of using the International Classification of Diseases (ninth revision, clinical modification) system in identifying patients with acute lower GI tract bleeding are important and well taken. However, this does not invalidate our main conclusions (1) that urgent colonoscopy infrequently leads to successful treatment in patients with acute lower GI tract bleeding and that exclusion of an upper GI source should be given priority over urgent colonoscopy. The frequency of distribution of diagnoses in our cohort may have differed because we only included patients who underwent urgent colonoscopy (i.e., within 24 h) as the initial diagnostic workup for acute lower GI tract bleeding. Therefore, patients with bleeding from adenocarcinoma or ischemic colitis may have been excluded because bleeding may have been less brisk. In our cohort, 5% (2/39) had a colorectal mass and 10% (4/39) had an “abnormal mucosa.” A histological diagnosis was available in only one patient whose mass was consistent with adenocarcinoma. Had we included more patients with ischemic colitis using the alternative proposed search method, the rate of finding a “definite” source of bleeding may have been higher. However, the rate of therapeutic intervention as a result of urgent colonoscopy would not have improved and would probably have been even lower. Application of therapy for bleeding from ischemic colitis is generally unnecessary and may be associated with more complications. In bleeding from adenocarcinoma, urgent colonoscopy could conceivably lead to therapeutic intervention as a bridge to more definitive surgical therapy. In our cohort, one of the four patients who received endoscopic treatment had a colon mass. Brisk hematochezia from colorectal cancer that might lead to urgent colonoscopy is infrequent. We doubt that there would have been a significant increase in the number of cases included in our cohort with the use of the alternative search method proposed. We agree with Dr. Longstreth that “the discovery of colorectal neoplasia often leads to effective therapy.” However, the scope of our article was limited to achieving successful hemostasis in acute lower GI tract bleeding. Surgical resection remains the definitive therapy in colorectal cancer. Similarly, we agree with his contention that the discovery of ischemic colitis may obviate the need for further testing and lead to earlier hospital discharge. However, the value of urgent colonoscopy evaluated in this study was its ability to achieve successful hemostasis rather than the successful outcome of any specific disease. Furthermore, our recommendation that exclusion of an upper GI source in a patient with severe hematochezia should be given priority over urgent colonoscopy is not very controversial. In conclusion, we accept that the proposed alternative search method should be considered in future research undertakings in this area. However, in our study, we doubt that this would have substantially altered our conclusions on the value of urgent colonoscopy in the evaluation and management of acute lower GI tract bleeding.