A Dedicated and Caring Staff
There’s a reason why our physicians are exceptional leaders. At TDI, we take a team management approach. We believe that your care should be monitored from all viewpoints. That is why we have created a team of endocrinologists, podiatrists, ophthalmologists, clinical researchers, pediatricians, nephrologists, wound care specialists, obstetricians, family practitioners, internal and rehabilitation medicine specialists, dietitians, certified diabetes educators and nurse case managers to address your needs as a patient. It’s important that you’re comfortable with your physician to ensure that your treatment is successful.

Our leadership team has hundreds of years of combined experience and are nationally recognized in their fields.

TDI Physician Leaders

Ralph A. DeFronzo, MD
serves as Deputy Director of the Texas Diabetes Institute. As one of the nation’s leading diabetes researchers, Dr. DeFronzo is also a Professor of Medicine and Chief of the Diabetes Division at the UTHSC at San Antonio and the South Texas Veterans Health Care System, Audie L. Murphy Division in San Antonio. He is a graduate of Harvard Medical School and served his Residency in Internal Medicine at Johns Hopkins Hospital. He has completed Fellowships in Endocrinology at the National Institutes of Health/Baltimore City Hospitals, and in Nephrology at the Hospital of the University of Pennsylvania.

Terri De La Haya, RN, BSN, MPH
serves as Vice President of the Texas Diabetes Institute. She has earned her Bachelor of Science degree in nursing from UTHSC Nursing School at San Antonio, and a Masters in Public Health from the UTHSC at Houston, School of Public Health.                                   

Charles Reasner II, MD
serves as Medical Director of the Adult Diabetes/Endocrinology Clinic at the Texas Diabetes Institute. Dr. Reasner is Professor of Medicine at the The UT Health Science Center (UTHSC) at San Antonio. He is a graduate of Loma Linda University School of Medicine in Loma Linda, California, and served his Residency at USAF Medical Center, Keesler Air Force Base in Mississippi. He completed a Fellowship in Endocrinology at USAF Wilford Hall Medical Center at Lackland Air Force Base in San Antonio, Texas.                      

Jan M. Bruder, MD
serves as Director of the Osteoporosis and Metabolic Disease Clinic at the Texas Diabetes Institute and Associate Professor of Medicine in the Division of Endocrinology at the UTHSC at San Antonio. She is a graduate of Louisiana State University in New Orleans, Lousiana and completed her Internal Medicine Residency at the Medical College of Virginia in Richmond. She also completed her Endocrine Fellowship at the University of Colorado in Denver.                        

Jane L. Lynch, MD
serves as a Medical Director of the Children's Center at the Texas Diabetes Institute and she serves as an Assistant Professor/Clinical in the Department of Pediatrics at the UT Health Science Center at San Antonio. She received a Bachelor's of Science in Microbiology from Indiana University in Bloomington, Indiana . She also received her medical degree from Wright State University School of Medicine in Dayton, OH.                        

Wajeh Qunibi, MD
is Medical Director of the Texas Diabetes Institute Adult Renal services and Associate Professor of Medicine at the UTHSC at San Antonio. He received his training in Internal Medicine in Baltimore, Maryland, completing a Fellowship in Nephrology at Baylor College of Medicine in Houston, Texas. He is board certified in Internal Medicine and Nephrology.

Eugenio Cersosimo, MD
is currently the Medical Director of Clinical Research at the Texas Diabetes Institute and an Associate Professor of Medicine at the UT Health Science Center at San Antonio. He obtained his medical degree at the Universidade Federal Fluminense in Rio de Janeiro, Brazil and moved to Vanderbilt University in Nashville, Tennessee where he graduated with a Ph.D. degree in Physiology and Metabolism. He served his medical residency training and Endocrinology fellowship program at the Mayo Clinic in Rochester Minnesota with a special degree in Clinical Investigation.

Heidi Becker, MD
serves as a Medical Director of Ophthalmology at the Texas Diabetes Institute and Assistant Professor in the Department of Ophthalmology. She graduated from Dartmouth Medical School in 2003 and completed her internship at the Texas Tech Health Science Center in El Paso, Texas in 2004. Dr, Becker completed her ophthalmology residency at UT Health Science Center at San Antonio in 2007.