Rheumatology Fellows

2022 Entering Fellows

Sandra Amara Ogbonnaya-Whittlesey, M.D.

Sandra Amara Ogbonnaya-Whittlesey (Amara), M.D., received her medical degree from the Keck School of Medicine of the university of Southern California in 2011. Dr. Ogbonnaya-Whittlesey completed her residency in Pediatrics at LAC-USC in 2015 and is a current fellow at Children’s National Medical Center. Dr. Ogbonnaya-Whittlesey volunteered as a medical student in India and South Africa. She has several oral and poster presentations to her credit. In addition to working as a primary care physician, she also taught medical students at UCLA for three years. Her interests and hobbies include family time and traveling.


Ecem Sevim, M.D.

Ecem Sevim, M.D., a current resident at Montefiore Medical Center/Albert Einstein College of Medicine, in Bronx, NY, received her medical degree from Istanbul University in 2012. Dr. Sevim previously spent two years as a research fellow at the Hospital for Surgery in New York doing research in rheumatology and has several publications in peer reviewed journals. Dr. Sevim is an experienced speaker having given 14 poster presentations and five oral presentations at venues such as the American College of Rheumatology and the International Congress of Internal Medicine. Her hobbies and interests include abstract art, jazz, snowboarding and traveling.


Dale Kobrin, M.D.

Dale Kobrin, M.D., completed his medical training at the Perelman School of Medicine of the University of Pennsylvania in 2019 and is a current resident at the Allegheny Health Network Medical Education Consortium, in Pittsburgh, PA. His research experience led to publications of manuscripts in peer reviewed journals. Dr. Kobrin is also the principal author of a book chapter on Castleman disease, a rare immunologic condition with abnormalities overlapping rheumatologic conditions. His interests and hobbies include film history and automotive repair and restoration.


2020 Entering Fellows

Christopher Redmond, M.D.

Dr. Christopher Redmond, M.D., received his undergraduate and medical degrees from Rutgers University. He developed an interest in autoimmune disease while completing a master’s in integrated Immunology at Oxford University. Following medical school, he completed his Internal Medicine-Pediatrics residency at the University of Kentucky. He is currently completing a combined pediatric and adult rheumatology fellowship at the Children’s National Hospital in Washington, DC, and NIH. He comes to the NIH with an interest in translational and clinical research with a focus in vasculitis.


2019 Entering Fellows

Omer N. Pamuk, M.D.

Omer N. Pamuk, M.D., graduated from Istanbul University, Istanbul Medical Faculty in Turkey. He completed his internal medicine residency training at Istanbul University, Cerrahpasa Medical Faculty. He gained laboratory research experience at Harvard Medical School, Beth Israel Deaconess Medical Center, Division of Rheumatology, and under the mentorship of Prof. Dr. George Tsokos explored the pathogenesis of multiple immune cell abnormalities in systemic lupus erythematosus. He took summer courses at the Harvard School of Public Health on Principles in Clinical Trials and Measuring Health Outcomes. He has extensive experience in both clinical and laboratory research. He has authored many multicenter studies and published articles in journals, like Arthritis Care Research, Arthritis Research & Therapy, Journal of Rheumatology, Clinical Rheumatology, Lupus, etc. He is interested in studying the mechanisms and epidemiology of autoimmune rheumatic diseases.


Dr. Yiming Luo

Dr. Yiming Luo received his medical degree at Peking University Health Science Center in Beijing, China. He completed his internal medicine residency at Mount Sinai St. Luke’s - Roosevelt Hospital Center, an affiliate of Icahn School of Medicine at Mount Sinai in New York City. Dr. Luo has conducted multiple research projects on rheumatic diseases and published 13 peer-reviewed articles. During his residency, he collaborated with prime researchers from Hospital for Special Surgery on outcome research. His study found a nationwide improvement of maternal mortality and other outcomes in lupus pregnancies over the past two decades. Dr. Luo gave an oral presentation on the study at the American College of Rheumatology Annual Meeting and the manuscript was recently accepted to the Annals of Internal Medicine. He joins the NIH rheumatology fellowship with an interest in pursuing clinical research on vasculitis.


2018 Entering Fellows

Photo of Brian Dizon

For Brian Dizon, M.D., Ph.D., his interest in immunology began during college at the University of Miami when he volunteered in a lab studying host-pathogen interactions using Yersinia as a model organism; he subsequently graduated with a major in microbiology/immunology. He then went to medical school through the Medical Scientist Training Program at the University of Alabama at Birmingham, and under the mentorship of Dr. John Kearney, studied the role of self-reactive carbohydrate-specific B cells and their secreted antibodies in the early stages of autoimmune diabetes in NOD mice. His interest in autoimmunity through all stages of life led him to complete a residency in internal medicine-pediatrics at the University of Rochester, and he now pursues a combined rheumatology fellowship at the NIH. As he continues his training, he hopes to further explore the multifaceted roles of B cells in autoimmune disease at the basic/translational level.


Dr. Sandra Williams

Dr. Sandra G. Williams earned her M.D./Ph.D. from Washington University in St. Louis, where her Biochemistry thesis project focused on understanding the evolution and molecular basis of RNA-protein interactions in a family of proteins found in the spliceosome. More recently, she completed residency training in Internal Medicine at Yale New Haven Hospital. She comes to the rheumatology fellowship at NIH with an interest in exploring the intersection of RNA biology and biochemistry with inflammatory disease.


2017 Entering Fellows

Photo of Dr. Marcela A. Ferrada

Marcela A. Ferrada, M.D., received her Doctor of Medicine degree from the Universidad del Valle in Cali, Colombia, in 2004. Shortly after graduation, she moved to the United States to pursue an academic career. She worked at the University of San Diego as a post-doctoral fellow for two years. For her clinical training, she went on to Internal Medicine Residency at the University of Miami/Jackson Memorial Hospital where she also spent a year as a Chief Resident. She then pursued dual fellowships in Critical Care at the National Institutes of Health and Infectious Diseases at Johns Hopkins Hospital. During her fellowships, she completed all the required courses for a Masters in Health Science from Duke University. Upon completion of her clinical fellowships, she stayed on as a Staff Clinician in Critical Care at the NIH. However, Dr. Ferrada was diagnosed with Relapsing Polychondritis in 2015 and decided to make the study of this disease her life’s work. She is currently a clinical fellow in the Rheumatology Fellowship training branch at the NIH. Dr. Ferrada was the federal liaison for the relapsing polychondritis foundation until December 2017. She has given more than ten Grand Rounds in various hospitals in the United States about Relapsing Polychondritis, and is currently working with Peter C. Grayson, M.D., James Katz, M.D., Robert Colbert M.D., Keith Sikora M.D. and other investigators to study the disease.


2016 Entering Fellows

Image of Blas Betancourt.

Blas Betancourt, M.D. earned his medical degree at the University of Medical Sciences of Villa Clara, Cuba. He completed residencies in clinical pharmacology at the University of Medical Sciences of Havana, Cuba, and internal medicine at Metropolitan Hospital/New York Medical College, New York. His research thesis during pharmacology training at the National Center of Scientific Research of Havana was based on animal models of inflammation. He has extensive experience in clinical research, with over 15 peer-reviewed articles and abstracts or book chapters. He previously worked in clinical development of biological products in different therapeutic areas at the Center for Biological Research of Havana. He then worked as a medical expert in the Medical Department at Bayer Healthcare Canada, and participated in international clinical trials in women's health care. Most recently, he worked as a resident in internal medicine at Metropolitan Hospital, where his main scholarly activity was related to the clinical utility of antinuclear antibodies.


Image of Ananta Subedi.

Ananta Subedi, M.D. received his Doctor of Medicine degree from the Kathmandu University of Dhulikhel, Nepal, and began residency in Internal Medicine at MedStar Good Samaritan Hospital, an affiliate of the Johns Hopkins School of Medicine in Baltimore, Md. He has given multiple presentations, including at the American College of Physicians and the American College of Rheumatology Annual meetings. He has authored numerous publications on topics, including the effect of mycophenolate on the white blood cell count and the frequency of infection in systemic lupus, and a case of high fever, elevated ferritin and pancytopenia. He is currently completing his M.P.H. at the University of Massachusetts.


2015 Entering Fellows

Image of Sara Alehashemi.

Sara Alehashemi, M.D. worked at the University of Pennsylvania before and during residency training at Pennsylvania Hospital, measuring the burden of atherosclerosis in rheumatic patients and also analyzing and interpreting molecular imaging findings in rheumatic diseases. She has 10 peer-reviewed publications and has given multiple presentations at national conferences. During her fellowship, she will work with Peter Grayson on vasculitis, with emphasis on advanced imaging techniques.


Image of Robinder Dhillon.

Robinder Dhillon, M.D. has extensive clinical and research experience in many locations, including the Center for Musculoskeletal Research in Rochester, New York, studying the effects of PTH on femoral allograft healing and angiogenesis. He is the first author on an original article in the Journal of Bone and Mineral Research, two review articles and a book chapter, and has coauthored five other peer-reviewed publications. He completed his residency at Wayne State University. During his fellowship, he will be working with Mike Ward on outcomes research, with emphasis on arthritis. He will also pursue an MSc in clinical epidemiology through the Duke-NIH Program.


Image of Maryam Gul.

Maryam Gul, M.D. has extensive research experience, including research at Cambridge University while at medical school, which resulted in her co-authoring a paper published in the New England Journal of Medicine on genetic risk for stroke. She has 13 peer-reviewed publications and has presented at multiple national scientific conferences, including the American College of Rheumatology Annual Meeting. During her fellowship, she will work with Nehal Mehta on inflammation and atherosclerosis in psoriasis and pulmonary hypertension.


2014 Entering Fellows

Image of Shubhasree Choudhury.

Shubhasree Dutta Choudhury, M.D. (Sree)

Internal Medicine Residency; Overlook Medical Center, New Jersey M.D.; Kolkata Medical College, India


Image of Megha Sawney.

Megha Sawhney, M.D.

Internal Medicine Residency; Cone Health University of North Carolina M.D.; Maulana Azad Medical College, India


2013 Entering Fellows

Image of Kyawt Shwin.

Kyawt Win Shwin , M.D.

Internal Medicine Residency; SUNY Downstate Medical Center, New York
M.D.; Institute of Medicine, Yangon, Myanmar


Image of Seema Patel.

Seema Kumar Patel, M.D.

Internal Medicine Residency; Mountainside Hospital, Montclair, NJ M.D.; American University of Antigua, St George, Antigua and Barbuda


This page last reviewed on July 17, 2020