Our Doctors
Harry J Wasvary, MD
Dr. Wasvary is a board-certified colon and rectal surgeon with over 20 years experience. He is an Associate Professor of Medicine, Chief of Colon-Rectal Surgery at William Beaumont Hospital (Royal Oak), and Director of Beaumont’s Multidisciplinary Colorectal Tumor Clinic.
Jason K Shellnut, MD
Jason Shellnut, M.D. is Board Certified in both General Surgery and Colon & Rectal Surgeon. He specializes in Robotic Colon and Rectal Surgery as well as endoscopic procedures for screening and surveillance of Colon and Rectal Cancer. Dr. Shellnut also serves as the Associate Director of the Endoscopic Unit at Royal Oak Beaumont Hospital and Assistant Professor at the Oakland University William Beaumont School of Medicine.
Matthew A Ziegler, MD
Matthew Ziegler, MD is a board-certified general and colon and rectal surgeon. Dr. Ziegler specializes in robotic and laparoscopic surgery, as well as colonoscopy. Dr. Ziegler commonly treats colorectal cancer, diverticulitis, inflammatory bowel disease and anorectal disorders including hemorrhoids, fissures, abscesses, and fistulas. He is the program director for the Beaumont Health fellowship training program in colon and rectal surgery.
Claire E Peeples, MD
Claire E. Peeples, MD, FACS, FACRS is a board-certified general and colon and rectal surgeon. Dr. Peeples specializes in robotic and laparoscopic surgery, as well as endoscopic procedures for screening and surveillance of colon and rectal cancers. Dr. Peeples commonly treats diverticulitis, inflammatory bowel disease and anorectal disorders including hemorrhoids, fissures, abscesses and fistulas.
John C Bauman, MD
Dr. Bauman is a board certified colon and rectal surgeon who joined Oakland Colon and Rectal after completing Colorectal Fellowship in 2020. He currently specializes in Colon and Rectal Surgery and offers colonoscopies as well.
Ginger Kleinert, Office manager
Ginger is the glue that holds us together. She makes sure we all have what we need, and helps our patients when they need assistance.
Christine Ghattas, Nurse Practitioner
Christine has been a registered nurse since 2015. She enjoyed working at Houston Methodist Hospital as well as Beaumont Royal Oak. General and colorectal surgery have been her passion since the start of her career. She thoroughly enjoyed taking care of patient’s in the operating room and wanted to gain more knowledge of the various disease processes. Pursuing her Master’s degree helped her reach that goal. She obtained her Master’s of Science degree in Nursing at the University of Michigan. Christine enjoys spending time with her family and friends. She has two kids that love playing soccer and being outdoors.