Gastroenterology & Hepatology

October 2021 - Volume 17, Issue 10

Letter From the Editor: Testing and Research Involving Hepatitis Delta Virus

Gary R. Lichtenstein, MD, AGAF, FACP, FACG

Hepatitis delta virus (HDV) has been called the worst form of human viral hepatitis, as Dr Jeffrey S. Glenn notes in this month’s issue of Gastroenterology & Hepatology. This disease has been underreported and undertested in the past, likely at least in part because of lack of effective treatment; thus, clinicians often thought that identifying infected patients was not important. However, this thinking is starting to change because of promising therapies in the pipeline. In our Advances in Hepatology column, Dr Glenn compares hepatitis delta antibody tests and HDV RNA tests, discusses whether commercial genotype tests and rapid diagnostic tests will be needed, and examines whether HDV RNA negativity should be considered a cure of this disease, among other issues involving HDV.

One of our feature articles this month highlights clip artifact on endoscopic mucosal resection (EMR) scars. As Dr Douglas K. Rex points out, clip artifact commonly occurs after prophylactic clips are used at EMR sites. Endoscopists may confuse clip artifact with residual neoplastic polyp, which can result in needless treatment. Thus, appropriate diagnosis and management of clip artifact is important for endoscopists who use prophylactic clips. Dr Rex reviews the efficacy of clip closure following colorectal lesion resection, characteristics of EMR scars, different types of clip artifact, analysis of pit patterns, and management of clip artifact. In addition, he provides a number of useful accompanying images.

Our other feature article focuses on the latest version of the Chicago Classification, which has been instrumental in high-resolution manometry (HRM) metrics and definitions of motility disorders. Dr Joel E. Richter outlines the historical development of HRM and the Chicago Classification and explains how version 4.0 differs from earlier versions. He also notes several important changes, including the refinement of the diagnosis of esophagogastric junction outflow obstruction, the exclusion of mechanical obstruction in suspected distal esophageal spasm and hypercontractile esophagus, and the use of a more restrictive metric for diagnosing ineffective esophageal motility. In addition, he mentions other areas that need to be addressed in future versions of the Chicago Classification.

Our Advances in IBD column provides an update on vedolizumab treatment in patients who have Crohn’s disease. Dr Brian Bressler discusses the current clinical trial and real-world data on the use of vedolizumab in this setting, the longest follow-up data currently available, the most common adverse events that have occurred, and which Crohn’s disease patients are the most appropriate candidates for vedolizumab therapy, among other issues.

The use of magnetic resonance (MR) elastography to predict treatment response in patients with nonalcoholic steatohepatitis (NASH) is explored in our NASH in Focus column. Dr Mazen Noureddin discusses how treatment response is defined, MR utility in this setting, the accuracy of MR elastography in predicting treatment response in clinical trials of NASH, and the link between MR elastography and outcomes of cirrhotic patients with NASH, along with related issues.

Finally, I would like to welcome Dr Klaus Mergener as the new section editor of our monthly Advances in Endoscopy column. This month’s column, featuring Dr Drew B. Schembre, highlights endoscopic innovations. His discussion includes the limitations of conventional endoscopy, innovations such as narrow-band imaging and volumetric laser endomicroscopy, the use of artificial intelligence, and how gastroenterologists can gain familiarity and expertise with endoscopic innovations.

I hope that you enjoy these articles and find them interesting and clinically useful.


Gary R. Lichtenstein, MD, AGAF, FACP, FACG

Millennium Medical Publishing, Inc