Clinical Leadership

The DaVita Patient-Focused Quality Pyramid, which includes complex clinical initiatives such as fluid and infection management—and other innovations that support clinical excellence, were created and driven by DaVita’s physician leaders, with group medical directors and physician partners, who have dedicated themselves to raising the standard of care for patients with kidney disease. They are shaping the future of kidney care by:

  • Developing a transformative vision of improved healthcare
  • Collaborating with a widespread physician community
  • Taking accountability for improving results
  • Addressing challenging clinical topics
  • Investing in physician development across all levels
  • Striving for a high level of physician satisfaction

Office of the Chief Medical Officer (OCMO)

DaVita established OCMO to ensure that a group of experienced nephrologists is dedicated to working with the business leadership at DaVita to provide value for patients, deliver high-quality outcomes and be responsible stewards of resources. OCMO focuses on the needs of DaVita's medical directors and nephrologists by strengthening the clinical-operational partnership and developing new tools and resources to help tackle the daily challenges in kidney care.

Mahesh Krishnan, MD, MPH, MBA, FASN | Chief Medical Officer, International; Group Vice President of Research and Development
Before joining DaVita Kidney Care, Mahesh Krishnan, M.D., served as medical director and global development leader for Epogen, where he played a key role in discussions with the FDA and the Centers for Medicare and Medicaid Services. He also assisted as executive director of medical policy for Amgen, and had a private practice in Virginia for nearly five years. He currently serves on the editorial board of Nephrology News and Issues and his writing has been published many times in renal care and research publications around the world. Dr. Krishnan earned his medical degree from Thomas Jefferson University, and holds a master's degree in Public Health from Johns Hopkins University and an MBA in Medical Services Management from the Johns Hopkins Carey School of Business.

Allen R. Nissenson, MD, FACP, FASN, FNKF | Chief Medical Officer, United States | @DrNissenson
Prolific author and renowned authority on kidney disease, Allen R. Nissenson, M.D., is emeritus professor of medicine at the David Geffen School of Medicine at UCLA, where he has served as director of the dialysis program and associate dean. Dr. Nissenson is also co-chair of the Kidney Care Partners Quality Initiative. He is a former president of the Renal Physicians Association (RPA) and served on the RPA Board of Directors as a special advisor to the president. Dr. Nissenson is a past president of the Southern California End-Stage Renal Disease Network. He is the author of more than 650 scientific papers and the editor of two dialysis textbooks, both in their 4th editions.

Stefan H Jacobson, MD, PhD | CEO And Professor Of Nephrology, Danderyd University Hospital
Professor Jacobson, in addition to being CEO and professor of nephrology at Danderyd University Hospital, is the associate editor of the Scandinavian Journal of Urology. Prior to Danderyd University Hospital, Professor Jacobson served first as the Head of the medical division and then as the director of the nephrology Department at Karolinksa Hospital and Korolinksa Institute. He has written or contributed to over 150 publications in journals around the world, and focuses his research on inflammation and cardio-vascular disease, leukocyte function, transmigration of leukocytes, IgA nephropathy and cardio renal syndrome. Professor Jacobson also serves on several international study and steering committees, with a focus on the randomized controlled study of the effects of hemodialysis (membrane permeability outcome study, MPO study), the practice pattern in hemodialysis (dialysis outcome practice pattern study, DOPPS), and the effects of cinacalcet (ECHO).

Maciej Drożdż, MD, PhD | Chief Medical Officer, Europe and the Middle East; Medical Director, Poland
As Chief Medical Director for DaVita’s operations in Europe and the Middle East, Dr. Drożdż worked for more than 20 years at University Hospital in Kraków and served as the head of the dialysis unit in the department of nephrology. He has written or contributed to nearly 40 journal publications, including six chapters in polish nephrological textbooks. His research focuses on cardiovascular challenges for dialysis patients and intradialytic anticoagulation. As both principal and co-investigator he took part in phase II, III and IV clinical trials.

André Weigert, MD, PhD | Chief Medical Officer, Portugal
Born in Rio de Janeiro, Brazil, Dr. André Weigert studied at the University of Lisbon, Portugal, before doing postgraduate training at Hospital S. Maria and Hospital Santa Cruz in Lisbon, Portugal, and Baylor College of Medicine in Houston, Texas. His professional credits include chief medical resident at the VAMC of Houston/BCM, the fellowship in nephrology at the University of Colorado, Denver and specialist degrees in internal medicine and nephrology (1996) and clinical pharmacology (2008). Additionally, Dr. Weigert obtained certification from the American Board of Internal Medicine (1992) and the American Board of Nephrology and Hypertension (1996), and was elected fellow of the American College of Physicians (1999). His work on more than 40 published studies (in English, Portuguese and French) includes several clinical studies involving the EVOLVE trial. Dr. Weigert currently works in the renal transplant unit of the Hospital Santa Cruz, is assistant professor of pharmacology at the University of Lisbon and is the Chief Medical Officer of DaVita in Portugal. He directs the dialysis unit, Eurodial, at Obidos-Gaeiras, with 170 patients—all of whom are doing online hemodiafiltration (HDF). He is also involved in studies of pulse wave velocity in patients undergoing HDF, as well as new approaches to anemia management. He participated in several ISN CMEs in African countries (including Angola, Mozambique, Zambia, Democratic Republic of Congo).

Abdulkareem Alsuwaida, MD, FRCPC, MSc | Chief Medical Officer, Saudi Arabia
Dr. Abdulkareem Alsuwaida received his medical degree from King Abdulaziz University and completed his postgraduate medical education and a master’s degree in clinical epidemiology in internal medicine and nephrology at the University of Toronto in Canada. Dr. Alsuwaida is chief medical director for DaVita in the Kingdom of Saudi Arabia, as well as a professor of medicine at King Saud University School of Medicine and consultant in the nephrology division at the King Khalid University Hospital. Previously he served as chairman for the department of medicine and director of postgraduate education at King Saud University, and president of the Saudi Society of Nephrology. His research is focused on dialysis, glomerulonephritis and lupus nephritis, and he has published more than 40 papers on these topics. Dr. Alsuwaida is a fellow at The Royal College of Physicians and Surgeons of Canada, as well as a member of the Saudi Society of Nephrology, the American Society of Nephrology College of Physicians and the European Society of Nephrology.

Grace Yan, MD, PhD | Medical Director, China
Before joining DaVita Kidney Care, Dr. Grace Yan worked at the prestigious Shanghai Renji Hospital, a class 3A hospital in China, where she spent 22 years in nephrology, including a post-doctoral year at the Renal Disease and Hypertension Department of the University of Colorado Health Science Center, Denver, Colorado. Dr. Grace earned her MD and PhD from Shanghai Jiao Tong University School of Medicine, where she currently advises MSc and PhD candidates. She is also a committee member of the Chinese Society of Internal Medicine and was a Youth Committee member of the Chinese Society of Nephrology. She has won a number of academic awards and has published extensively.

Suresh Sankar, MD, MBBS, MBA, FRCP, FASN I Medical Director, India
Dr. Suresh Sankar has 16 years of experience as a Clinical Nephrologist and was a group medical director for 3 years. He is certified by the American Board of Nephrology and the American Board of Internal Medicine. An alumnus of Madras Medical College, Dr. Sankar completed his nephrology training at the University of Rochester in New York and is a Fellow of American Society of Nephrology and Fellow of the Royal College of Edinburgh. He has a keen interest in clinical research, epidemiology, and health systems and has published more than 50 original papers and abstracts on those topics. He was honored with the Indian Society of Nephrology’s Young Investigator Award and Janssen-Cilag Award of Excellence in 2006.

Sylvia P. B. Ramirez, MD, MPH, MBA I Chief Medical Officer, Asia Pacific
Dr. Sylvia P. B. Ramirez is a clinical nephrologist and a population epidemiologist with more than 20 years of research, public policy and nephrology experience. Before becoming the chief medical officer for DaVita in Asia Pacific she was vice president of global research and development for Arbor Research Collaborative for Health, and remains a consultant there. She was principal investigator and coinvestigator for multiple projects for the United States Centers for Medicare and Medicaid Services, including the Evaluation of ESRD Disease Management Demonstration, the Quality Incentive Payment Demonstration and the ESRD Measures Support Work. She is also a coinvestigator for the Dialysis Outcomes and Practice Patterns Study. Dr. Ramirez has published multiple papers on ESRD care, and has led a variety of technical expert panels on the development of quality performance measures in U.S. dialysis facilities.

Werner Kleophas, MD, PhD I Chief Medical Officer, Germany Professor

Dr. Werner Kleophas’s career began in the mid 1980’s in the medical department of Ferdinand Sauerbruch Klinikum Wuppertal (Wuppertal, Germany). From there, he advanced to Deutsches Diabetes Forschungsinstitut Düsseldorf and Nephrological Clinic Heinrich Heine Universität Düsseldorf before starting work as a nephrologist and diabetologist in 1990 at Gemeinschaftspraxis (Düsseldorf, Germany), where his work continues today and where he took part in the development of the Genius dialysis machine. In addition, Professor Kleophas is a fellow of the American Society of Nephrology and sits on numerous editorial boards dedicated to nephrology and diabetology. Professor Kleophas was also among the first in Germany to establish combined programs for patients with diabetes mellitus and chronic kidney disease. His range of experience, coupled with his deep understanding of clinical trials (comprising authorship of numerous publications), serve him well in his role as chief medical officer of DaVita in Germany.

André Weigert, MD, PhD I Chief Medical Officer, Portugal
Born in Rio de Janeiro, Brazil, Dr. André Weigert studied at the University of Lisbon, Portugal, before doing postgraduate training at Hospital S. Maria and Hospital Santa Cruz in Lisbon, Portugal, and Baylor College of Medicine in Houston, Texas. His professional credits include chief medical resident at the VAMC of Houston/BCM, the fellowship in nephrology at the University of Colorado, Denver and specialist degrees in internal medicine and nephrology (1996) and clinical pharmacology (2008). Additionally, Dr. Weigert obtained certification from the American Board of Internal Medicine (1992) and the American Board of Nephrology and Hypertension (1996), and was elected fellow of the American College of Physicians (1999). His work on more than 40 published studies (in English, Portuguese and French) includes several clinical studies involving the EVOLVE trial. Dr. Weigert currently works in the renal transplant unit of the Hospital Santa Cruz, is assistant professor of pharmacology at the University of Lisbon and is the Chief Medical Officer of DaVita in Portugal. He directs the dialysis unit, Eurodial, at Obidos-Gaeiras, with 170 patients—all of whom are doing online hemodiafiltration (HDF). He is also involved in studies of pulse wave velocity in patients undergoing HDF, as well as new approaches to anemia management. He participated in several ISN CMEs in African countries (including Angola, Mozambique, Zambia, Democratic Republic of Congo).

Mauricio Ruiz Martinez, MD I Chief Medical Officer, Colombia
Dr. Mauricio Ruiz Martinez has been Chief Medical Officer for DaVita in Colombia since 2013. Previously he served as Associate Professor Chair of Nephrology and Semiology on the faculty of medicine at Universidad del Rosario and at La Fundación Universitaria de Ciencias de la Salud, both in Bogotá, and served as director of dialysis services at San José Hospital for more than 10 years. Additionally, Dr. Ruiz was coordinator of the peritoneal dialysis programs at Fresenius Colombia from 2004 to 2009 and was a Genzyme renal advisor from 2008 to 2010. He has also contributed chapters to many books on internal medicine and nephrology and is coeditor of the latest edition of the nephrology text in the Collection of the CIB (Corporación de Investigaciones Biológicas) in Colombia.

Awards & Recognition

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