Marcel B. Twahirwa, M.D.

Medical Director of DHR Health Diabetes & Endocrinology Institute

Dr. Marcel Twahirwa is Board Certified in Internal Medicine and Board Certified in Endocrinology, Diabetes and Metabolism. He is a resident of Rio Grande Valley and fluent in both English and Spanish. He graduated from La Universidad de Montemorelos, Nuevo Leon, MX. He completed his residency in Internal Medicine at New York Medical College, Metropolitan Hospital, New York, NY. In addition, he completed a fellowship program in Diabetes, Endocrinology and Metabolism at the University of Pennsylvania, Philadelphia, PA. He received his Board Certification in Internal Medicine in 1996 and his Board Certification in Endocrinology, Diabetes and Metabolism in 2000. Dr. Twahirwa has been taking care of patients with diabetes in the Rio Grande Valley since he moved to South Texas in 1998. He practiced at Diabetes and Endocrine Center from 1999 until May 2011 when he accepted the position of Medical Director at DHR Health Diabetes & Endocrinology Institute.

Dr. Twahirwa strongly believes in empowering the patient through education and he believes education is really the key to help stop diabetes. He is passionate about his work and a leader in advocacy for early detection, treatment and prevention of diabetes. Dr. Twahirwa has a special interest in research and has been working in conjunction with other physicians on clinical trials at DHR Health to find treatments for diabetes and other chronic health conditions.

Melany Castillo, M.D.

Dr. Melany Castillo specializes in endocrinology, diabetes, and metabolism. She is fluent in both English and Spanish.

Dr. Castillo received her medical degree from the University of Bucaramanga. She completed residency training in internal medicine at the University of Miami Department of Medicine and Jackson Memorial Hospital, where she also conducted fellowship training in metabolism and endocrinology.

Juan Diego Palacios, M.D.

Dr. Juan Diego Palacios is board certified in Internal Medicine and contributes his knowledge to help in the fight against diabetes and to treat other metabolic and endocrine disorders. Dr. Palacios received his medical degree from Universidad de Cuenca in Cuenca Ecuador. He conducted residency training in Internal Medicine at the University of Miami JFK Medical Center, where he was named Chief Medical Resident. He continued his training with a fellowship in Endocrinology, Diabetes & Metabolism at the University of Miami - Jackson Memorial Health System and was named Chief Endocrinology Fellow.

Alejandro Gonzalez, M.D.

DHR Health is proud to welcome Dr. Alejandro Gonzalez to the Joslin Diabetes Center Affiliate. Dr. Gonzalez specializes in endocrinology, diabetes, and metabolism. His expertise will help lead the battle to conquer diabetes through innovative approaches to clinical care and patient education.

Dr. Gonzalez received his medical degree from Universidad Del Norte Medical School in Barranquilla, Colombia. He completed residency training in Gastrointestinal Oncology at Memorial-Sloan-Kettering in New York, NY, and residency training in Internal Medicine at New York Downtown Hospital in New York, NY and Bridgeport Hospital/ Yale University in Bridgeport, CT. He received fellowship training in Endocrinology and Metabolism at the University of Texas Medical Branch in Galveston, TX.

Surya Narayan Mulukutla, M.D

Pediatric and Adult Diabetes and Endocrinology

DHR Health is proud to welcome Dr. Surya Narayan Mulukutla to the DHR Health Diabetes and Endocrinology Institute. Dr. Mulukutla is board certified in both internal medicine and pediatrics.  He specializes in the diagnosis and treatment of hormone disorders and diabetes across the age spectrum.

Dr. Mulukutla grew up in Corpus Christi, Texas before moving to Houston to become a Rice University / Baylor College of Medicine Medical Scholar.  After receipt of his medical degree, he remained at Baylor College of Medicine to complete his residency training in both internal medicine and pediatrics, as well as dual fellowship training in both pediatric and adult endocrinology, diabetes, and metabolism.  Dr. Mulukutla’s dual fellowship training allowed him to spend time with the nation’s experts, learning how to treat a variety of conditions ranging from pediatric thyroid disorders at Texas Children’s Hospital to endocrine cancers at MD Anderson Cancer Center.  During this time, he received commendations for clinical excellence as well as scholarly contributions from Baylor College of Medicine and the Endocrine Society.

Jose Gamez, M.D.

Pediatric Endocrinology

DHR Health is proud to welcome Dr. Jose Gamez to the DHR Health Diabetes and Endocrinology Institute. Dr. Gamez is board certified in pediatrics and board eligible in pediatric endocrinology. He specializes in the diagnosis and treatment of hormone disorders and diabetes in children.

Dr. Gamez received his medical degree from the National University of Colombia. He completed pediatric residency training at Bosque University in Bogotá, Colombia. He also completed pediatric residency training and a fellowship in pediatric endocrinology at Winthrop University Hospital in Mineola, New York.

Maggie Salinas

Center Administrator

Maggie Salinas is the Center Administrator at DHR Health Diabetes & Endocrinology Institute. She has been working in the medical field for 16 years. She started in private practice and has been working alongside Dr. Twahirwa for the past 14 years. Her priorities are exemplary customer service and managing the clinic using innovative strategies to meet the needs of the community.

Mayra J. Cantu, MSN, FNP-BC

Advanced Practice Registered Nurse

Mayra received her Bachelor of Science in Nursing degree from the University of Texas Pan American. In May of 2014, she earned her Masters of Science in Nursing degree from the same university. Mayra is certified as a Family Nurse Practitioner by the American Nurses Credentialing Center and is a member of Sigma Theta Tau National Honor Society. Since 2009, she has been practicing healthcare in both hospital and outpatient settings.

Mayra feels honored to be able to practice and be a member of the team at DHR Health Diabetes & Endocrinology Institute. Throughout her career development Mayra has witnessed the impact diabetes can have on patients, family members, and the community. With her education, desire to learn and dedication to her profession, Mayra strives to deliver the most compassionate and competent care. She believes in treating patients with respect, compassion and empowering them to make healthy decisions about their lifestyle and treatment options.

Lizlette Quintanilla

Registered Dietitian Nutritionist

Lizlette has a Bachelor of Science Degree in Dietetics from The University of Texas- Pan American. Through the Coordinated Program of Dietetics she realized the profound impact and need for nutrition and diabetes education across the valley. Lizlette has made it her personal goal to deliver individualized patient-centered nutritional care.

Alexandra Garza-Ibanez

Registered Dietitian

Alexandra received her Bachelor of Science Degree in Dietetics from The University of Texas-Pan American in 2011. Alexandra is an experienced dietician with training in the critical health care and outpatient settings. In the outpatient setting Alexandra is dedicated to educating patients on the self-management of diabetes. She strongly believes that education is the key for the prevention and treatment of many chronic conditions.

Annette Y. Ozuna, Pharm. D.

Clinical Pharmacist

Dr. Annette Y. Ozuna earned her Doctor of Pharmacy degree from the University of Texas-College of Pharmacy in May 2004.  Dr. Ozuna is originally from the Rio Grande Valley and has been serving our community for over 10 years in both outpatient and hospital settings, including working and managing her own independent retail pharmacy.  Dr. Ozuna has completed certificate training programs for Delivering Mediation Therapy Management Services, Pharmacy-Based Immunization Delivery and The Pharmacist and Patient-Centered Diabetes Care.

Dr. Ozuna is honored to have been given the opportunity to embrace the concept of pharmaceutical care and become part of the diabetes care team for DHR Health Diabetes & Endocrinology Institute.  Her passion for assisting diabetic patients in the management of their condition came from a strong family history of diabetes. It is Dr. Ozuna’s goal to empower patients by actively involving patients in their care and educating them about their disease state and medications.  Dr. Ozuna is most rewarded by the interactions, relationships, and trust built on a daily basis with patients while seeing improvement in their condition.

Stephanie Zeneé Martinez, Pharm. D.

Clinical Pharmacist

Dr. Stephanie Martinez is one of two clinical on staff pharmacists at the DHR Health Diabetes & Endocrinology Institute who acts as a resource for medication information.

Dr. Martinez is a native of the Rio Grande Valley and completed her prerequisite curriculum at the University of Texas Pan American before attending the University of Texas at Austin for her graduate pharmacy studies.  In May of 2014, Dr. Martinez graduated second in her class from the University of Texas – College of Pharmacy. After graduation, Dr. Martinez returned to the Valley and began working in the retail setting until she became part of the Clinical Pharmacy staff at DHR Health in March of 2015.

Dr. Martinez’s life goal has always been to return to the Rio Grande Valley and serve her community. Her career goal is to aid patients in receiving the most benefit from their medications.  Through education and empowerment, Dr. Martinez hopes to provide patients with a greater understanding of how their medications work, why each of their medications are important, as well as, the most beneficial way to take their medications while avoiding drug-related adverse effects.