Our Physicians

At Colorado Gastroenterology, our physicians are board certified in gastroenterology, actively involved in research and education, and have been recognized for their excellence by 5280 Magazine and Best Doctors in America.

Jennifer Brenner, MD

Dr. Jennifer Brenner was born and raised in Denver, Colorado. She graduated magna cum laude from Washington University in St. Louis with the focus of study on biology and anthropology. She received her medical degree from Loyola University Chicago, Stritch School of Medicine. Dr. Brenner completed her Internal Medicine residency at the University of Texas, Southwestern and completed her gastroenterology fellowship at the University of Texas Houston/MD Anderson Cancer Center. She is board certified in internal medicine and gastroenterology. She is a member of the American Gastroenterology Association and the American College of Gastroenterology. She was in private practice in Colorado Springs prior to moving back to Denver. She has a passion for women’s health issues concerning gastrointestinal health and liver diseases. In her free time she enjoys spending time with her family and friends, the outdoors, and playing the piano.

Jeffrey Frank, MD

Dr. Jeffrey Frank is a Denver native who received his medical degree from the University of Colorado School of Medicine and was selected in to the Alpha Omega Alpha honor society as a junior medical student. He completed his internal medicine residency at the University of Iowa Hospitals and Clinics and his fellowship in gastroenterology at the Mayo Clinic in Rochester, Minnesota. He is Chief of Gastroenterology at Exempla Saint Joseph Hospital. Dr. Frank has been selected as a Top Doc in 5280 Magazine multiple times through the years. Dr. Frank has actively taught medical students and residents from the University of Colorado Health Sciences Center and Exempla Saint Joseph Hospital throughout his career. He has been married for 23 years and has four children.

Kevin Sieja, MD

Dr. Kevin Sieja was born and raised in Chicago, Illinois. For his undergraduate studies, he attended the University of Notre Dame, graduating summa cum laude. He received his medical degree from Northwestern University where he was elected to Alpha Omega Alpha honors society. Dr. Sieja then completed his internal medicine residency and fellowship in gastroenterology at the University of Colorado Health Sciences Center. During fellowship, his research interests in disorders of the liver and intestine led to multiple publications. He is actively involved in clinical research and teaching. Dr. Sieja mentors residents from the University of Colorado. He specializes in all disorders of the digestive system and liver. Dr. Sieja is Board Certified in both Internal Medicine and Gastroenterology and is a member of the American Gastroenterological Association, the American College of Gastroenterology and the American Society of Gastrointestinal Endoscopy. Dr. Sieja’s wife, Amber, is an internal medicine physician in Denver. They enjoy the outdoors and spending time with their three children.

Thomas Trouillot, MD

Dr. Trouillot was born and raised in New York City. He received a BA in Intellectual History from Brandeis University and his medical degree from the University of California, San Francisco School of Medicine in 1989. He completed his internal medicine residency and gastroenterology fellowship at the University of Colorado Health Sciences Center. Afterwards, he joined the faculty as an Assistant Professor for five years specializing in liver disease. In 2001, he left academic medicine and entered private practice in gastroenterology and hepatology. He enjoys teaching and continues to give GI and liver-related lectures to physicians. Dr. Trouillot is a member of the American Gastroenterological Association and th American Association for the Study of Liver Diseases. He is a member of the medical staff at Presbyterian/St. Lukes, Exempla Saint Joseph, and Rose Medical Centers. He is married with two children.

In Memoriam

Kenneth Weiner, MD

Dr. Weiner retired from practice in June 2009. He was born and raised in Denver, Colorado. He received his BA from Stanford University and his medical degree from the Case Western University School of Medicine in 1988. He completed his internal medicine residency and chief residency at the University of Colorado, and then performed his Gastroenterology fellowship at the University of California, San Diego. He returned to Denver in 1994 to begin private practice. In recognition of his excellent patient care, he was chosen as a Top Doc in 5280 Magazine nine times.