The rate of therapeutic intervention in this population is very low; therefore, patients with melena and a nondiagnostic upper endoscopy who are stable and without evidence of ongoing bleeding may be able to safely undergo elective colonoscopy.
This study is the largest to-date to examine the diagnostic yield of colonoscopy to investigate melena after a nondiagnostic upper endoscopy in patients from a broad geographic distribution and a variety of clinical practice settings. The study appears in the April issue of GIE: Gastrointestinal Endoscopy, the monthly peer-reviewed scientific journal of the American Society for Gastrointestinal Endoscopy (ASGE).
Melena is the passage of dark tarry stools containing decomposing blood that is usually an indication of bleeding in the upper part of the alimentary canal. The alimentary canal is a long tube made up of the esophagus, stomach, small intestine, and large intestine into which food is taken and digested and from which wastes are passed out of the body. Melena is most frequently caused by an upper gastrointestinal (GI) bleeding source, however, upper endoscopy can be nondiagnostic for a specific source of bleeding in approximately one-fourth of cases in this patient population. It is known that blood in the cecum (the beginning of the large intestine) can also result in melena, demonstrating that lower GI bleeding sources can cause melena. Consequently, colonoscopy is frequently performed in patients with melena after a nondiagnostic upper endoscopy in order to exclude a lower GI source of the melena.
Previous studies on the diagnostic yield of colonoscopy in patients with melena described a relatively high rate of finding sources of bleeding. These small studies found diagnostic yields of 23 percent to 35 percent for colonoscopy in this patient population.
"We performed this study to describe the diagnostic yield and rate of therapeutic intervention of colonoscopy in this patient population and compare the diagnostic yield with a control population of average-risk patients having screening colonoscopies. We hypothesized that the diagnostic yield of colonoscopy in this clinical setting is lower than previously described but higher than that of average-risk screening patients and that the rate of therapeutic intervention during colonoscopy in patients with melena and a nondiagnostic upper endoscopy is low," said study lead author Jason P. Etzel, MD, Oregon Health and Science University, Portland. "Our results showed an overall low rate, 4.8 percent, of locating a bleeding source on colonoscopy. In addition, the rate of therapeutic intervention during colonoscopy for bleeding was very low at 1.7 percent, suggesting that the majority of these procedures are diagnostic only and could be performed on an elective basis."
This was a retrospective case-control study that involved patients in the Clinical Outcomes Research Initiative (CORI) database with a colonoscopy performed to investigate melena within 30 days of a nondiagnostic upper endoscopy for the same indication. A control group had colonoscopies performed for average-risk screening. The CORI database is an endoscopic database that collects data from community, academic, and Veterans Affairs settings across a broad geographic area in the United States. Main outcome measurements were the endoscopic finding of a suspected bleeding source, defined as right-sided arteriovenous malformation, colitis, polyp ¡Ý 20 mm, tumor, or ulcer, as well as the rate of therapeutic intervention during colonoscopy.
A total of 1,743 colonoscopies were performed to evaluate melena after a nondiagnostic upper endoscopy for the same indication. The melena population included more individuals with advanced age, more men, higher American Society of Anesthesiologists (ASA) Physical Status Classification System scores, and more warfarin use than average-risk screening controls. Melena-related colonoscopies were more likely to be conducted on inpatients, have lower quality bowel preparation, and have fellow involvement than colonoscopies on controls. Colonoscopy was performed the same day as upper endoscopy in 59 percent of cases.
All of the anticipated sources of suspected bleeding were more prevalent in patients with melena, except for polyps ¡Ý 20 mm in the right side of the colon. The overall rate of finding a suspected lower GI bleeding source in patients with melena was 4.76 percent compared with 1.28 percent in the control population. Notably, colon tumors were nearly three times more likely in the patients with melena than the average risk screening control group. The overall rate of endoscopic therapy in the population with melena was low, with therapy being performed in 1.7 percent of melena-related colonoscopies.
The researchers concluded that the diagnostic yield of colonoscopy to investigate melena after a nondiagnostic upper endoscopy is lower than previously reported. Moreover, the rate of therapeutic intervention in this population is very low; therefore, patients with melena and a nondiagnostic upper endoscopy who are stable and without evidence of ongoing bleeding may be able to safely undergo elective colonoscopy. Colonoscopy remains useful in this group of patients as they are at increased risk of colorectal cancer. The decision on timing of colonoscopy must be made based on an assessment of the overall clinical context.
About the American Society for Gastrointestinal Endoscopy
Since its founding in 1941, the American Society for Gastrointestinal Endoscopy (ASGE) has been dedicated to advancing patient care and digestive health by promoting excellence in gastrointestinal endoscopy. ASGE, with more than 12,000 members worldwide, promotes the highest standards for endoscopic training and practice, fosters endoscopic research, recognizes distinguished contributions to endoscopy, and is the foremost resource for endoscopic education. Visit www.asge.org and www.screen4coloncancer.org for more information and to find a qualified doctor in your area.
Endoscopy is performed by specially-trained physicians called endoscopists using the most current technology to diagnose and treat diseases of the gastrointestinal tract. Using flexible, thin tubes called endoscopes, endoscopists are able to access the human digestive tract without incisions via natural orifices. Endoscopes are designed with high-intensity lighting and fitted with precision devices that allow viewing and treatment of the gastrointestinal system.
Anne Brownsey | EurekAlert!
Statistical method developed at TU Dresden allows the detection of higher order dependencies
07.02.2020 | Technische Universität Dresden
Novel study underscores microbial individuality
13.12.2019 | Bigelow Laboratory for Ocean Sciences
The operational speed of semiconductors in various electronic and optoelectronic devices is limited to several gigahertz (a billion oscillations per second). This constrains the upper limit of the operational speed of computing. Now researchers from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg, Germany, and the Indian Institute of Technology in Bombay have explained how these processes can be sped up through the use of light waves and defected solid materials.
Light waves perform several hundred trillion oscillations per second. Hence, it is natural to envision employing light oscillations to drive the electronic...
Most natural and artificial surfaces are rough: metals and even glasses that appear smooth to the naked eye can look like jagged mountain ranges under the microscope. There is currently no uniform theory about the origin of this roughness despite it being observed on all scales, from the atomic to the tectonic. Scientists suspect that the rough surface is formed by irreversible plastic deformation that occurs in many processes of mechanical machining of components such as milling.
Prof. Dr. Lars Pastewka from the Simulation group at the Department of Microsystems Engineering at the University of Freiburg and his team have simulated such...
Investigation of the temperature dependence of the skyrmion Hall effect reveals further insights into possible new data storage devices
The joint research project of Johannes Gutenberg University Mainz (JGU) and the Massachusetts Institute of Technology (MIT) that had previously demonstrated...
Researchers at Chalmers University of Technology, Sweden, recently completed a 5-year research project looking at how to make fibre optic communications systems more energy efficient. Among their proposals are smart, error-correcting data chip circuits, which they refined to be 10 times less energy consumptive. The project has yielded several scientific articles, in publications including Nature Communications.
Streaming films and music, scrolling through social media, and using cloud-based storage services are everyday activities now.
After helping develop a new approach for organic synthesis -- carbon-hydrogen functionalization -- scientists at Emory University are now showing how this approach may apply to drug discovery. Nature Catalysis published their most recent work -- a streamlined process for making a three-dimensional scaffold of keen interest to the pharmaceutical industry.
"Our tools open up whole new chemical space for potential drug targets," says Huw Davies, Emory professor of organic chemistry and senior author of the paper.
12.02.2020 | Event News
16.01.2020 | Event News
15.01.2020 | Event News
21.02.2020 | Medical Engineering
21.02.2020 | Health and Medicine
21.02.2020 | Physics and Astronomy