Donald F. Kirby, MD, FACP, FACN, FACG, AGAF, FASPEN, CNSC, CPNS. Director, Center for Human Nutrition Medical Director, Intestinal Transplant Program; Professor of Medicine Staff, Gastroenterologist Digestive Disease and Surgical Institute, Cleveland Clinic, Cleveland, OH. Dr. Kirby is a gastroenterologist who specializes in Nutrition at the Cleveland Clinic in Cleveland, Ohio. He is Board Certified in Internal Medicine, Gastroenterology and Nutrition Support. His practice encompasses from very malnourished patients, who may require intravenous nutrition, to those with morbid obesity. In addition, he is the Director for the Center for Human Nutrition and the Medical Director for the Intestinal Transplant Program.