Mustafa Kinaan, M.D., FACE

Fellowship Program Director

Dr. Kinaan received his medical degree from Weill Cornell Medicine – Qatar. He joined the inaugural internal medicine residency class at the UCF COM / HCA Healthcare GME in 2014. He served as a chief medical resident at the Orlando VA Medical Center. Afterwards, he continued his medical training with UCF COM / HCA Healthcare GME as an endocrinology fellow. He served as a chief endocrinology fellow as well. During his training, Dr. Kinaan received several awards and recognitions including the Fellow Clinical Skills Award and Resident Humanitarian Award. Following his graduation from our fellowship program, Dr. Kinaan joined our team as an Assistant Clinical Professor of Medicine at UCF College of Medicine and a core faculty member at the endocrine fellowship and internal medicine residency programs. Dr. Kinaan received the Osler Award and GME Clinical Teaching and Mentorship Award in appreciation for his teaching skills. As a member of the Premier Endocrinology group, Dr. Kinaan provides endocrine services at HCA Florida Osceola Hospital and the practice locations.

Dr. Kinaan is an active member of the Endocrine Society, American Association of Clinical Endocrinologists, American Thyroid Association, Pituitary Society, and other professional organizations. He has special interest in medical education and is proactive about teaching learners of different levels and curriculum development. He is also engaged in research and quality improvement projects focusing on diabetes and glucometrics. He has special interest in inpatient endocrinology, diabetes, and adrenal disorders.




Orlando VA Medical Center


Hanford Yau, MD, CCD, FACP, FACE

Chief of Section of Endocrinology at Orlando VAMC
Associate Program Director

Dr. Hanford Yau is a native of San Francisco, CA, and earned his bachelor of science degree in bioengineering from The University of California, San Diego in La Jolla, California. He later earned his MD degree from New York Medical College in Valhalla, New York. Subsequently, he completed his residency in Internal Medicine at Naval Medical Center San Diego in San Diego, California, followed by fellowship in Endocrinology, Diabetes, and Metabolism at the University of Florida, in Gainesville, Florida. He served seven years as a Navy physician including stints as general medical officer on the Wasp-class amphibious assault ship, USS Bataan (LHD 5) along with the 26th Marine Expeditionary Unit, and as division chief of Internal Medicine at Naval Hospital Oak Harbor, WA.


Dr. Yau most recently was an Assistant Clinical Professor of Medicine at The University of California, San Francisco (Fresno Campus), before returning to Florida joining as a staff endocrinologist at the Orlando VA Healthcare System in 2015 where he currently serves as the Site Director of Endocrinology, Diabetes, and Metabolism fellowship training at the Orlando
Veterans Affairs Medical Center.


He is a member of a number of national professional associations and their respective committees, and currently is serving a second term as the vice president of the Florida Endocrine Association [formerly the Florida Chapter of the American Association of Clinical Endocrinologists
(AACE)]. Dr. Yau has presented nationally, co-authored, peer-reviewed, and served as invited editor for various publications on endocrinology-related topics with focus on endocrine oncology, neuroendocrine tumors, adrenal hypercortisolism, nuclear medicine, and osteoporosis.

Akin Eraslan, M.D.

Dr. Eraslan is a board certified endocrinologist in Orlando VA Medical Center. He did his internal Medicine training in the University of Mississippi. He completed fellowship in the University of Michigan in 2006. After working as an endocrinologist in the private practice, he joined Orlando VA Medical Center in 2009. He practices general endocrinology with special interest in calcium, parathyroid and bone disorders. He is an active member of Endocrine Society and American Association of Clinical Endocrinologists (AACE).

Dr. Eraslan has basic research experience in microcirculation and he holds M.S. degree in circulation physiology.

Sowmya Suryanarayanan, M.D., MRCP, FACE, FACP, ECNU

Dr. Sowmya Surya is an Associate Professor of Medicine at University of Central Florida and a core Faculty Member of the UCF/HCA/VA Joint Consortium for Endocrinology Fellowship. She serves as the Chair of the Inpatient Glycemia/PSAT Committee and the Gestational Diabetes Subcommittee at the Orlando VAMC. Her training spans three continents wherein she started her medical school in India and completed her residency and fellowship in England as Member of Royal College of Physicians and then has trained at Brown University in Rhode Island for her Internal Medicine Residency, before going on to University of Michigan Ann, Arbor, MI for her  Endocrinology Fellowship. Dr. Surya is Certified in  Diabetes Technology, Bone density through ISCD and  Endocrine Certification in Neck Ultrasound from American College of Clinical Endocrinologists. She was selected as one of the 3 Fellows in the Nation to do her brief training at the National Institutes of Health and won the Genentech Best poster award for the Annual Endo Society conference as Endocrine Fellow in 2005. She recently certified as Clinical Teacher with Stanford Faculty Development course and certified in Clinical Research through Orlando VAMC.

Dr. Surya won Best Clinician Award in 2019 and Osler award for Best Teacher from her Endocrine Fellows in 2023. Her main research interest was Growth Hormone in Obesity and she published in many journals. Dr. Surya is passionate about bedside teaching of thyroid and parathyroid ultrasound to her trainees. She helped expand several services at the Orlando VAMC, mainly simulation of thyroid ultrasound and fine needle biopsies, creating insulin templates and protocols for intravenous insulin in non-DKA veterans in the intensive care setting, in addition to protocols for adrenal vein sampling and dynamic endocrine testing and developing a Gestational Diabetes program for pregnant veterans at the Orlando VAMC and its affiliated sites. Dr. Surya has been recognized as Top Doctor/ Endocrinologist by Orlando’s Top Physicians magazine for 2 years in a row.

Dr. Surya is a member of the American College of Physicians, American College of Subspecialties, American College of Clinical Endocrinology and Endocrine Society, Diabetes Technology Society and Florida Endocrine Association. She has served in several subcommittees of Endocrine Society.

Ali Rizvi, M.D.

Dr. Ali Rizvi has held clinical and academic faculty positions at the Medical College of Georgia, University of South Carolina, and Emory University. He previously served as Endocrinology Division Chief and Program Director at the University of South Carolina School of Medicine. He has had extensive experience in caring for patients with endocrine and metabolic disorders. Dr. Rizvi has mentored junior faculty, endocrinology fellows, internal medicine residents, and medical students. He has also received research grants and teaching awards and authored scholarly publications.

Hilda Merino-Chavez, M.D.

Dr. Merino-Chavez received her medical degree at the Central University of Ecuador and later moved to United States to complete her postgraduate and medical training at the University of Central Florida.

She obtained a master’s degree in Molecular Biology and Microbiology at the Burnett School of Biomedical Sciences. Her thesis work on the use of stem cells for cardiovascular disease won the award for outstanding master’s thesis. Dr. Merino-Chavez has research experience and has published various peer reviewed publications and case reports.

Dr. Merino-Chavez completed her Internal Medicine residency and Endocrinology fellowship training at UCF COM/HCA Healthcare GME where she was awarded the resident teacher award, humanitarian award, among others. After finishing her training, she worked as endocrinologist at a private practice in local Orlando and later returned to the Orlando VAMC as a full-time endocrinologist. She is also an Assistant Professor of Medicine at UCF College of Medicine.

Dr. Merino-Chavez is board certified in Internal Medicine and Endocrinology, Diabetes and Metabolism. She maintains membership in various professional organizations, including the American Association of Clinical Endocrinologists and the Endocrine Society. She has volunteered in various community clinics in the area that assisted under-served populations. Dr. Merino-Chavez enjoys teaching fellows, residents and medical students.  Dr. Merino-Chavez has special interest in obesity medicine and adrenal pathology.

Sondra O’Callaghan, PA-C, MPH, CHES



Sondra O’Callaghan earned her bachelor’s degree from the University of South Florida.  She then completed her Physician Assistant training and degree at Trevecca Nazarene University.  To enhance the patient encounter, especially as it relates to patient education, she earned her MPH from the University of North Florida and became a Certified Health Education Specialist.  She has practiced Endocrinology for 21 years in both the private and federal sectors.

She practices full time at the Orlando VA Healthcare System where she enjoys taking care of our Nation’s Veterans.  She, herself, is a Veteran of the United States Army and trained as a Combat Medic.  She participates in the Endocrinology, Diabetes, and Metabolism Fellowship training, and she also trains providers on conducting end of life conversations with patients.   Administratively, she is a PA advocate and has served on the Medical Executive Committee.

She maintains membership in professional organizations including being Past-President of the American Society of Endocrine Physician Assistants and working with the American Diabetes Association to plan and implement community diabetes programs. 




HCA Florida Osceola Hospital




Theresa Fynn, M.D.

Dr. Fynn is board-certified in Endocrinology and Internal Medicine. After Dr. Fynn completed her undergraduate studies at the University of Ghana, she finished medical school at the University of Ghana School of Medicine and Dentistry. She then went through a residency in internal medicine and a fellowship in endocrinology, both at Howard University in Washington, DC.

Dr. Fynn founded the Premier Endocrinology practice in Osceola County in Florida. She provides comprehensive outpatient and inpatient endocrinology in Kissimmee, St. Cloud, and Orlando areas. She has been a faculty member at the UCF COM / HCA Healthcare GME Endocrinology, Diabetes, and Metabolism fellowship since its foundation. Dr. Fynn is passionate about teaching fellows and residents. She received the Osler Award in appreciation for her teaching skills. Dr. Fynn regularly volunteers in a community clinic in Osceola to help under-served patients with endocrine disorders. Dr. Fynn has special interest in diabetes and thyroid disorders.

Kwame Ntim, M.D., ECNU

Dr. Ntim received his medical degree from the University of Ghana School of Medicine and Dentistry. He completed both an internship and residency in internal Medicine at St. Agnes Hospital in Baltimore, and a fellowship in Endocrinology, Diabetes, and Metabolism at the University of Florida.

Dr. Ntim previously held the role of assistant professor at the University of Florida College of Medicine under the division of Endocrinology. During this time, he also served as the thyroid clinic director at the Malcom Randall Veterans Affairs (VA) Medical Center in Gainesville.

He has a passion for training the next generation of endocrinologist and has been a faculty member at the UCF COM / HCA Healthcare GME Endocrinology, Diabetes, and Metabolism fellowship since its foundation. He carries the Endocrine Certification of Neck Ultrasound (ECNU). He joined Premier Endocrinology shortly after the practice was established. He provides comprehensive inpatient and outpatient endocrinology in Kissimmee, St. Cloud, and Orlando areas. He participates in quality improvement and patient safety initiatives in HCA Florida Osceola Hospital. His interest include thyroid disorder and calcium disorders. He holds membership in several endocrine societies.

Dionardo Medina Encarnacion M.D., CCD, ECNU, DABOM

Dr. Medina received his medical degree from Autonomous University of Santo Domingo. He finished his internship and Internal Medicine residency at St. Barnabas Hospital, affiliated with Albert Einstein College of Medicine in New York. He finished Endocrinology, Diabetes and Metabolism fellowship at University of Central Florida / HCA Healthcare, in Orlando, where he also served as chief endocrinology fellow. After finishing Endocrinology Fellowship, Dr. Medina moved to northeast Pennsylvania to work at Geisinger Health (now Risant Health), in its endocrinology department, where he treated patients and served as Medical Director. There he also served as Faculty for the Internal Medicine Residency Program, teaching medical residents and students. Dr. Medina moved back to Florida in 2023 to be one of the partners at Premier Endocrinology, where he also provides endocrine services to HCA Florida Osceola Hospital.

Dr. Medina is board-certified in Internal Medicine, Endocrinology, Diabetes and Metabolism by the American Board of Internal Medicine. He is also certified in Weight Loss Medicine by the American Board of Obesity Medicine. Additionally, Dr. Medina is Endocrine-Certified in Neck Ultrasonography (ECNU), and a Certified Clinical Densitometrist (CCD). 

Dr. Medina is a member of several medical and endocrine societies including American Association of Clinical Endocrinologist, Endocrine Society, Obesity Medicine Association, American Thyroid Association and American College of Physicians.

Dr. Medina enjoys teaching fellows, residents and medical students. He has special interest in thyroid nodules/cancer, parathyroid, pituitary, weight loss medicine and general endocrinology.


UCF Health – Gateway Clinic




Amita Kathuria, M.D.

Dr. Amita Kathuria is board-certified in Endocrinology and Internal Medicine. Dr. Kathuria received her M.D. from the University of Florida College of Medicine in Gainesville, FL, where she also did her residency training in Internal Medicine. She completed a fellowship in Endocrinology, Diabetes and Metabolism from Virginia Commonwealth University in Richmond, VA. She did her undergraduate work at Wellesley College, Wellesley, MA, earning a B.A. in Biochemistry with a minor in Economics. Dr. Kathuria joined the UCF Health team and the UCF COM / HCA Healthcare GME Endocrinology, Diabetes, and Metabolism fellowship in 2020.

Before joining UCF Health, Dr. Kathuria was a faculty member and practicing physician in Internal Medicine and Endocrinology at the University of Florida College of Medicine, Shands Hospital at the University of Florida, the University of Texas Southwestern Medical Center and Parkland Memorial Hospital. She is a member of the American Association of Clinical Endocrinologists and the Endocrine Society and has received numerous awards for excellence in teaching and scientific research.



Program Administrator



Jennifer Barcom



I am a Florida native with 30 years healthcare experience with a degree in Medical Office Management. I have been with HCA GME for 4 years and love my job. I enjoy GME and find being a part of the journey is fulfilling. I am a mom/stepmom of 3 and a Grammy of 7. I love spending time with family and friends, going to Disney, baking and enjoying empty nest life with my husband.