Our Renal Care Physicians, Nurses, and Administrators

Physicians

Harold Locay, M.D.

Dr. Locay was the first of our physicians to come out of a nephrology fellowship at the University of Miami School of Medicine and joined Ocala Kidney Group in 1994. He is a leader in the local medical community and has at various times served as Chief of Staff, Chief of Medicine and in other roles at Munroe Regional Medical Center, aka, Advent Health Ocala. In addition, he was instrumental in forming Ocala Kidney Group’s research arm, Discovery Medical Research. Dr. Locay is Board Certified in Nephrology and Internal Medicine and has served as Medical Director for the DaVita Ocala East Hemodialysis Unit. Dr. Locay is now certified by the American Society of Diagnostic and Interventional Nephrology (ASDIN).

Dr. Locay’s wife and family are all very active in the community and have with their church done several mission trips to Central America over the years.

Harold Locay, M.D.

Izu Nwakoby, M.D.

After medical school in Lagos, Nigeria, Dr. Nwakoby returned to his roots in New York City for Residency and Nephrology Fellowship at the Albert Einstein College of Medicine in The Bronx. He was regularly at the top of his academic classes, and was Intern of the Year and Chief Medical Resident in those respective programs. He could have joined any nephrology practice in the country, and chose to come to the Ocala Kidney Group in 2002. He has been a consistent advocate for the nephrology patients in Marion County, is loved by his patients, and tremendously well regarded in the Ocala Medical Community. Dr. Nwakoby is Board Certified in both Internal Medicine and Nephrology, and serves as the Medical Director for the DaVita Ocala North Hemodialysis Unit.

Dr. Nwakoby and his wife have lived in Ocala since 2002. Their son and daughter are both on their way to academic achievement of their own in the magnet schools here in the community.

Izu Nwakoby, M.D.

Timothy Rogers, M.D.

Dr. Rogers’ academic career included medical school at the University of Connecticut School of Medicine. He completed an Internal Medicine Residency at Baystate Medical Center in Springfield, MA, and a Nephrology fellowship at the University of Miami. He joined the Ocala Kidney Group in 2003, and in 2007 was able to become the first partner in the group to train to perform interventional procedures on patient dialysis vascular accesses. He has been entirely focused on this work since 2008, and performs the procedures at our Leesburg, Florida location. Dr. Rogers is nationally recognized as one of the most prolific and successful nephrologists performing these services in the country. He is Board Certified in Nephrology, as is now certified by the American Society of Diagnostic and Interventional Nephrology (ASDIN).

Dr. Rogers, his wife and two children have lived in Ocala since 2003. His extracurricular activities include running and weight training. He also enjoys coaching and watching his kids play soccer and, as well as following the sports programs of his alma mater, the University of Notre Dame.

Timothy Rogers, M.D.

Mahesh Vaghela, M.D.

Dr. Vaghela left a post as an associate professor in the kidney transplantation department at the University of Florida to join Ocala Kidney Group in 2007. Board Certified in both Nephrology and Internal Medicine, he also has a sub-specialty area of concentration in kidney transplantation, which he attained through additional training throughout his medical career, and through a special additional fellowship he undertook at UCLA Medical Center. Throughout all his years of training and practice, though, his primary focus remains the care of his patients. Among the many academic achievements, he attained over the years, he is perhaps most proud of the “Barbara Sloan Patient Comfort Award” achieved in his residency for outstanding compassion and care of patients. Dr. Vaghela is Board Certified in both Nephrology and Internal Medicine and serves as the Medical Director for the DaVita Silver Springs Shores Hemodialysis Unit.

Dr. Vaghela is also known for his past roles as Chairman – Credential Committee, Past President and Board Member, Chief of Staff, VP Chief of Staff, Treasurer, Chief of Medicine and VP Chief of Medicine for Munroe Regional Medical Center, aka, Advent Health Ocala. Dr. Vaghela also plays a current role in Faculty Appointment as Assistant Professor, University of Central Florida – Nephrology Specialty.

Dr. Vaghela, his wife, and two daughters have lived in Ocala since 2007.

Mahesh Vaghela, M.D.

Oleksandr Kovalchuk, M.D.

Dr. Kovalchuk gained automatic entry into medical school in his native Ukraine in recognition of his accomplishments as the most accomplished chemistry student in the entire country that year. This was typical of the honors awarded him in his subsequent academic career, which included residency at the Yale-affiliated Danbury Hospital, and nephrology fellowship at the Albert Einstein College of Medicine/Montefiore in the Bronx, NYC. He found time along the way to also earn a Masters of Public Health in Epidemiology and International Health from the University of Alabama at Birmingham. Dr. Kovalchuk is Board Certified in Internal Medicine and Nephrology, and has been with Ocala Kidney Group since 2009. He also serves as the Medical Director for the DaVita Acute (i.e. hospital inpatient) dialysis program.

Dr. Kovalchuk is an avid and accomplished tennis player; he and his wife have a young son and a daughter.

Oleksandr Kovalchuk, M.D.

Venkat Chitumalla, M.D.

After medical school in India, Dr. Chitumalla was a resident at Michigan State University, followed by a nephrology fellowship at St. John Medical Center in Detroit, Michigan. Dr. Chitumalla is Board Certified in both Internal Medicine and Nephrology.

Michigan was important for Dr. Chitumalla; along with his medical degrees, he also met and married his wife there. They have lived in Ocala with their two young children since Dr. Chitumalla joined Ocala Kidney Group in 2011.

Venkat Chitumalla, M.D.

Saila Ventra, M.D.

Dr. Saila Ventra studied Medicine, Surgery and Pediatrics in her native India before her Internal Medicine residency at the Aurora Health Care System in Milwaukee, Wisconsin. She then moved to Harvard’s prestigious Beth Israel Deaconess Medical Center for Nephrology Fellowship. She joined Ocala Kidney Group in 2011, and along with her husband and two young sons have settled right in to the Ocala community.

Dr. Ventra is Board Certified in both Internal Medicine and Nephrology.

Saila Ventra, M.D.

Rebecca Ong, M.D.

Dr. Rebecca Paras Ong studied medicine at University of Santo Tomas after graduating with honors in BS Biology at De La Salle University in the Philippines. She then proceeded to do her Internal Medicine Residency at St. Peter’s University Hospital in New Brunswick, NJ, where she was awarded Best Resident of the year when she graduated. She completed her Nephrology fellowship training at University of South Florida in Tampa, Fl and has moved to Ocala since 2015. Dr. Ong is board certified in Internal Medicine and Nephrology.

Dr. Ong’s clinical interests include evaluating patients with chronic kidney disease, managing hypertension and glomerular diseases. She remains competitive in her field by staying up to date with the latest researches or clinical trials in Nephrology presented in annual conferences.

Besides being a nephrologist, she holds a 4th dan blackbelt in taekwondo, and participates in regional and national taekwondo tournaments with husband and son, who are both blackbelters in taekwondo.

Rebecca Ong, M.D.

Nicoleta Radoianu, M.D.

Dr. Nicoleta Radoianu is board certified in Internal Medicine and Nephrology. She studied medicine at Carol Davila University in Bucharest, Romania where she received merit-based scholarship. She completed her Internal Medicine Residency at St. Luke’s Hospital in Bethlehem, PA, and the Nephrology fellowship training at University of South Florida in Tampa, FL.

She has published articles in various fields of medicine and presented at many medical conferences.

Dr. Nicoleta is fluent in Spanish and English. Dr. Radoianu lives now in Ocala with her husband and their two young children.

Nicoleta Radoianu, M.D.

Joel Adewuyi, M.D.

Dr. Joel Adewuyi studied Medicine and Surgery at Lautech teaching hospital in Nigeria. He then started his residency training in OBGYN in Nigeria, before relocating to the United States to join his family.

In the United States, he initially worked as a dialysis technician where he developed his interest in the field of Nephrology.

He then proceeded to do his Internal Medicine Residency at the University of Central Florida/HCA Consortium Ocala Regional Medical Center where he graduated in 2020. He completed his Nephrology fellowship training at University of Florida Health in Gainesville, Florida in June 2022. Because of his love for the great city of Ocala and his children desires, he immediately moved back to Ocala and Joined Ocala Kidney Group after his fellowship training.

Dr. Adewuyi has presented interesting medical cases at many medical conferences and continues to increase his knowledge daily. He has clinical interests in evaluating patients with all forms of kidney diseases and hypertension.

Dr. Adewuyi and his wife live in Ocala, Florida. His three children who love Ocala dearly are on their way to academic achievement of their own in the magnet school her in Ocala.

Joel Adewuyi, M.D.

ARNP

Philip Dankyi, ARNP

Philip Dankyi completed his Masters Degree in Nursing from the University of Florida in 1997, after having been honored with the “Exceptional Performance and Achievement by an International Student” award. The following year he achieved certification as a Nurse Practitioner and joined the Ocala Kidney Group where he has been a tremendous asset ever since. Philip conscientiously attends the annual National Kidney Foundation clinical meetings and other conferences to ensure he is bringing to bear in the freshest information available to the nephrology community. His practice at this time is in support of the patients of Doctors Nwakoby, Vaghela, and Kovalchuk. His pleasant demeanor and extensive experience are appreciated by both his patients and coworkers.

Philip and his wife reside here in Ocala, their sons are pursuing academic and professional careers in various places around the Southeast.

Philip Dankyi, ARNP

COMING SOON

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Briana Oliveros, ARNP

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Rebekah Costello, ARNP

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Jessica Chitumalla, ARNP

Administrative Leadership

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Rafael L. Mulet, Vice President of Strategic Planning, Execution & Chief Administrative Officer

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Marilyn Vazquez, Finance Manager

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Janet Acosta-Nazario, HR Coordinator and Administrative Assistant

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Zina Padgett, Practice Operations and Billing Manager

COMING SOON

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Our Renal Care Physicians, Nurses, and Administrators

Physicians

Harold Locay, M.D.

Izu Nwakoby, M.D.

Timothy Rogers, M.D.

Mahesh Vaghela, M.D.

Oleksandr Kovalchuk, M.D.

Venkat Chitumalla, M.D.

Saila Ventra, M.D.

Rebecca Ong, M.D.

Nicoleta Radoianu, M.D.

Joel Adewuyi, M.D.

ARNP

Philip Dankyi, ARNP

Briana Oliveros, ARNP

Rebekah Costello, ARNP

Jessica Chitumalla, ARNP

Administrative Leadership

Rafael L. Mulet, Vice President of Strategic Planning, Execution & Chief Administrative Officer

Marilyn Vazquez, Finance Manager

Janet Acosta-Nazario, HR Coordinator and Administrative Assistant

Zina Padgett, Practice Operations and Billing Manager

Jose Arias, Vascular Access Center Manager

Main Office

West Office

Dialysis Vascular Access Center