Meet Our Providers
Masi Khaja, MD
Austin, TX. Gastroenterologist
Capitol GastroDr. Khaja grew up in the Morristown and Jersey City areas of New Jersey from the age of 10, after moving there with his family. His childhood dream was to become a doctor, and in 1999 he saw his dream come true when he graduated with a medical degree. He completed his internship in Brooklyn’s New York Methodist Hospital, an affiliate of Cornell University, where he felt drawn to the field of Gastroenterology, in which he now specializes.
Dr. Khaja is fellowship-trained, board-certified, and has an impressive record of publication in notable medical journals. His mission is to reduce the number of people colon cancer effects by promoting prevention and early detection of the disease through regular screening.
Sridhar P. Reddy, M.D.
My research was primarily involved with Intracellular pH measurements in Rabbit Esophageal Epithelium using Florescent Microscopy. We identified various membrane transport channels involved in pH regulation of esophageal epithelial cells. The aim of these experiments is to identify the mechanism of acid injury and methods to prevent it.
Professional / Society Memberships:
American College of Gastroenterology – Member
Texas Medical Association
Travis County Medical Society
Tomoko Hattori, PhD, MSN, RN, APRN, AGCNS-BS
Tomoko is a board-certified Adult/Gerontology Clinical Nurse Specialist and Advanced Practice Registered Nurse in Texas. She earned her Master of Science in Nursing from the University of Texas at Austin. Before becoming a CNS, she cared for patients in long-term care, where she developed a deep appreciation for the unique needs of chronic care.
Prior to her nursing career, Tomoko earned a Ph.D. in Neuroscience from UT Austin and worked as a lab manager studying neuroendocrinology and motivation. Her background in neuroscience nurtured a deep understanding of how the brain and body work together to influence health and well‑being.
She brings this perspective to every patient interaction, emphasizing compassionate, evidence‑based care tailored to each individual. She is committed to shared decision-making, empowering patients to be active participants in their care. In addition to her clinical role, she is involved in nursing research at UT Austin, supporting breast cancer patients and survivors of East Asian descent through targeted interventions.
In her free time, Tomoko enjoys spending time with family and friends, crafting, and exploring new restaurants in Austin.
Kayla McCarthy, PA-C
Kayla is a Physician Assistant certified by the National Commission on Certification of Physician Assistants. She completed her Bachelor of Science degree in Pre-Medicine from the University of Dayton in Ohio and her Master of Physician Assistant Studies from Dominican University in River Forest, Illinois. She has a life-long passion for gastroenterology and prioritizes spending time with patients explaining the importance of preventive health maintenance and regular screening procedures. Kayla works to develop treatment plans with patients based on their individual preferences and concerns. She also takes part in clinical research with hopes of expanding the number of medical management options available to patients. In her free time, she enjoys traveling, spending time with friends and family and cheering on the Cleveland Browns.
Sabrin Rahman, NP
Sabrin Rahman, DNP, is a board-certified nurse practitioner who earned her Doctor of Nursing Practice degree from the University of Texas Health Science Center at San Antonio. She is passionate about preventive care and believes early detection and patient education are key to improving long-term health outcomes. In her practice, she focuses on preventive gastroenterology, including colorectal cancer screening through colonoscopy, as well as the evaluation and management of a wide range of digestive health conditions.
Before becoming a nurse practitioner, Sabrin spent several years working in gastroenterology as a registered nurse, which helped build a strong clinical foundation in digestive health. This experience continues to guide her patient-centered approach to care, where she emphasizes clear communication, education, and shared decision-making.
Sabrin is dedicated to helping patients better understand their conditions and feel empowered to take an active role in their health. She remains committed to continuing education and staying current with evolving practices in gastroenterology.