Internal Medicine Residency Faculty
Work directly alongside faculty members who are deeply invested in your learning needs, professional goals and personal well-being.
Meet our residency leaders and faculty
Our faculty members share a passion for education and patient care. You’ll feel this passion in our supportive learning environment as we help you continue your medical education and achieve your learning, research and career goals.
John Conzemius, MD
Originally from central Minnesota, Dr. Conzemius has been at Gundersen for over 20 years. He completed his Internal Medicine Residency at Gundersen in 2003 after graduating from the University of Minnesota School of Medicine. Dr. Conzemius has been involved in both inpatient and outpatient medical student and resident education throughout his career at Gundersen. He served as associate program director for the Transitional Year Residency Program from 2021 until stepping into the role of interim program director for the Internal Medicine Residency in 2024.
Dr. Conzemius also maintains a busy Internal Medicine primary care practice, serves as a rotating attending for the Inpatient General Medicine teaching service and is an attending for the Internal Medicine Residency Continuity Clinic.
In his spare time, he enjoys all that the La Crosse area has to offer with hiking, biking, golfing, skiing, snowshoeing, boating and attending theatre and musical productions.
Michael Witcik, MD, FACC
Dr. Michael Witcik grew up in Northern Wisconsin and graduated from the University of Wisconsin-Madison School of Medicine and Public Health. He is a cardiologist with interests in valvular heart disease and percutaneous therapies, advanced echocardiography and cardiac MRI. He has five kids and enjoys outdoor activities and sports, such as hiking, camping, skiing, basketball and hockey.
Thomas Leece, MD
Dr. Tom Leece is an associate program director of the Internal Medicine Residency at Gundersen. He works as a hybrid physician covering both inpatient and outpatient medicine patients at Gundersen. He is an avid music fan and enjoys building his record collection, sharing this hobby with his four children. He and his family are also avid skiers during the winter months.
Core faculty and staff
Derek Hupp, MD
Aiman Riaz, MD
Kelsey Fischer, DO
Internal Medicine Junior Faculty
Cindy Leitz, C-TAGME
Internal Medicine Residency administrator
Elizabeth Parent
Internal Medicine Residency assistant
Family life during your residency
Why Gundersen
Call La Crosse Home
We have it all in La Crosse, Wis. Our vibrant city and region support your dream lifestyle with a welcoming community, culture and outdoor adventure.
Housing
Steps from our flagship medical center in La Crosse, our housing options allow you to enjoy the company of your family and the comradery of your colleagues.
Prioritizing Your Wellness
As you learn how to become the clinician you aspire to be, we’ll provide space to prioritize your mind and body wellness, and reach the work-life balance you need.