1 Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA. timothy.zaki@utsouthwestern.edu.
2 Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA.
3 Department of Pathology, Dallas VA Medical Center - VA North Texas Healthcare System, Dallas, TX, USA.
4 Department of Radiology, Dallas VA Medical Center - VA North Texas Healthcare System, Dallas, TX, USA.
5 Division of Gastroenterology and Hepatology, Dallas VA Medical Center - VA North Texas Healthcare System and University of Texas Southwestern Medical Center, Dallas, TX, USA.