Meet your team! Our greatly experienced and board-certified doctors specialize in all aspects of kidney disease. We have all pledged and dedicated ourselves to providing the highest quality and personalized kidney care while building long-term partnerships with patients, their families, and their other healthcare providers.
Dr. Co is a board-certified nephrologist and joined Columbus Nephrology, Inc. in February 2022, though she has been a well-known and trusted member of the Central Ohio nephrology community for several years. She received her medical degree from The University of Philippines College of Medicine. She completed her internal medicine/pediatrics residency at West Virginia University and nephrology training at Allegheny General Hospital
Dr. Kovach is board-certified nephrologist. He graduated from the University of Notre Dame and Case Western Reserve University Medical School. He completed his internal medicine residency and nephrology fellowship at Washington University in St Louis.
Dr. Ramaswamy is a board-certified nephrologist and immediate past President of Columbus Nephrology, Inc. He received his degree from Kilpauk Medical College. In addition to extensive medical training and research in Great Britain, he completed internal medicine residency at Long Island Hospital in New York and fellowship in nephrology at Vanderbilt University.
Dr. O’Reilly is a board-certified nephrologist and current President of Columbus Nephrology. He graduated from The Ohio State University Colleges of Pharmacy and Medicine. He completed his internal medicine residency and nephrology fellowship at the University of North Carolina-Chapel Hill.
Dr. Stephen Roderer is a board-certified nephrologist with expertise in internal medicine and nephrology. A proud Buckeye, Dr. Roderer completed his undergraduate studies, medical degree, residency, and nephrology fellowship all at The Ohio State University. He joined Columbus Nephrology in 2019, where he focuses on providing comprehensive care in general nephrology. Dr. Roderer is dedicated to improving the health and well-being of his patients through high-quality, compassionate care.
Dr. Ravish Shah is a board-certified nephrologist with expertise in interventional nephrology and fluoroscopic-guided peritoneal dialysis catheter placements. He received his medical degree from Dr. D. Y. Patil Medical College in Mumbai, India, and completed his residency at Southern Illinois University in Springfield, Illinois. Dr. Shah further honed his skills during his nephrology fellowship at The Ohio State University. He joined Columbus Nephrology in 2014 and is dedicated to advancing kidney care through innovative techniques. Outside of work, Dr. Shah enjoys spending time with his family, as well as participating in sports, traveling, and exploring diverse cultures around the world.
Dr. Nick Stoycheff is a board-certified nephrologist with a focus on dialysis access and interventional nephrology procedures. He earned his medical degree from Ohio State University College of Medicine and completed his residency at the University of Maryland in Baltimore, Maryland. Dr. Stoycheff further advanced his training with a fellowship at Tufts Medical Center in Boston, Massachusetts. He has been a valued member of Columbus Nephrology since 2009. Dr. Stoycheff holds a Master of Science in Clinical Research from Tufts University and has been recognized as a Castle Connolly Top Doctor in Columbus for his excellence in patient care. Outside of his professional pursuits, Dr. Stoycheff enjoys spending time with his family and engaging in various outdoor activities.
Dr. Zakaryan is a board-certified nephrologist with a commitment to advancing kidney care through both patient care and research. After receiving his medical degree from Yerevan State Medical University in Armenia, he completed his internal medicine residency at Mount Carmel Health System in Columbus, Ohio. During his nephrology fellowship at The Ohio State University, Dr. Zakaryan was recognized as the most distinguished nephrology fellow for two consecutive years. In addition to his clinical practice, he is actively involved in clinical research, contributing to the development of innovative treatments. Dr. Zakaryan has been a valued member of Columbus Nephrology since 2017.
Charles Boyer is a certified physician assistant with over three decades of experience in nephrology and interventional nephrology. He graduated from Lake Erie’s Physician Assistant Program in 1986 and dedicated 32 years to working at the University of Michigan Medical Center, specializing in nephrology. After retiring, Charles returned to Ohio to continue his academic and personal pursuits.
In addition to his clinical expertise, Charles holds a Master of Arts in Buddhist Studies from the University of Sunderland, a Master of Science in Bioethics from Union Graduate College and Mount Sinai School of Medicine, and a Doctorate of Bioethics from Loyola University of Chicago.
Sefenesh Mamai, is a certified Adult Gerontology Acute Care Nurse Practitioner specializing in nephrology. She earned both her Bachelor of Science in Nursing and Master of Science from Mount Carmel College of Nursing and has been a valued member of Columbus Nephrology since 2020. Sefenesh focuses on general nephrology and kidney replacement therapies, bringing a strong commitment to delivering high-quality, individualized care for patients managing kidney disease.