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Dr. Tonya R. Callender is a nurse practitioner in the Department of Obstetrics and Gynecology at UTMB. She is also the Director of the Women‘s Comprehensive Care clinic. Dr. Callender, who grew up in northwest Oklahoma, received a bachelor's degree in nursing from Southwestern Oklahoma State University in Weatherford, Oklahoma, a master's degree and a doctorate of nursing practice from UTMB's School of Nursing. She has 24 years of service with the University of Texas Medical Branch.

Dr. Callender is a runner and enjoys biking and snowboarding. Her greatest joy is being a grandmother. As a UTMB alumna, Dr. Callender is a strong supporter of the institution's mission to improve health for the people of Texas and around the world. She has a passion for working on behalf of her patients and is strongly committed to their needs and well-being.

Russell R. Snyder, M.D., is the Vice Chair of the Department of Obstetrics and Gynecology and the Director of the Division of Gynecology at UTMB and is the holder of the endowed Faculty Distinguished Chair in Obstetrics and Gynecology Honoring Drs. Al Leblanc, Harry Little, and Charlie Powell. Dr. Snyder received his medical degree from the University of Texas Medical School at Houston, and completed his residency in Obstetrics and Gynecology at Wilford Hall USAF Medical Center in 1982. He subsequently completed a fellowship in Gynecologic and Breast Pathology at the Armed Forces Institute of Pathology in Washington, D.C., in 1984. He retired from the USAF in 1997 as the Chairman of the Department of Obstetrics and Gynecology at Wilford Hall and Consultant to the Surgeon General for Obstetrics and Gynecology. Dr. Snyder has made UTMB his home since then.

Dr. Snyder is board-certified in Obstetrics and Gynecology and has been an oral board examiner for the American Board of Obstetrics and Gynecology since 1996. He currently sits on the Board of Directors for the Exxcellence Foundation for Women's Health and is a past member of the Board of Directors for the American Board of Obstetrics and Gynecology and the American Board of Family Medicine. He is currently on the Editorial Board for Clinical Updates in Women's Health Care and is one of the editors of the text book Step Up to Obstetrics and Gynecology. He is a reviewer and past member of the editorial board for the journal Obstetrics and Gynecology. He is also a past member of the executive board of the American College of Obstetricians and Gynecologists and has been very active in other College activities and committees to include the Committee for Obstetric Practice. He is also a member of the FDA Medical Devices Advisory Panel for Obstetrics and Gynecology.

Dr. Snyder's clinical interests include gynecologic surgery, evaluation of abnormal pap-smears, vulvar disorders, abnormal bleeding, PMS, contraception, absence of periods, and the management of menopausal symptoms.

Dr. Cecil Kumfa is a graduate of the Windsor University School of Medicine in St Kitts, West Indies. She completed her residency at Richmond University Medical Center in New York and her Geriatric Medicine fellowship at the University of Texas Medical Branch in Galveston.

Dr. Kumfa is an assistant professor of Geriatric Medicine and serves as attending faculty on the ACE (Acute Care for the Elders) Unit, Geriatric Consults, and Geriatric Clinic Service. Dr. Kumfa currently serves as the director of the Acute Care for the Elders Unit, as well as the Medical Director of Gulf Health Care Center in Galveston.

Dr. Caryl Guillermo received her medical degree from the University of the East Ramon Magsaysay in the Philippines. She completed her residency in Family Practice at the Wichita Falls Family Practice Residency Program, an affiliate of UT-Southwestern in Dallas. Dr. Guillermo is following in the footsteps of her father, Dr. Benjamin Guillermo, who has been a practicing physician in the Clear Lake-area for over 15 years. Dr. Guillermo is board certified with the American Board of Family Medicine. She is a member of the American Academy of Family Practice and American Medical Association. Dr. Guillermo's practice philosophy is to help her patients by listening and caring for them physically, emotionally, and spiritually. She believes in empowering her patients through active participation in their treatment plan and overall health. She loves taking care of entire families and has a special interest in women's health and well-being.

When Dr. Guillermo is not at work taking care of her patients, she enjoys spending time with her family. Dr. Guillermo is a member of Bay Harbour United Methodist Church in League City. Her hobbies include reading, shopping, bowling, and tennis.

Dr. Fatima Khan joined UTMB Health in May of 2016. She was born in the UK and was raised in Pakistan. She graduated from medical school at the Aga Khan University Medical College in Karachi, Pakistan in 2003. She completed her Internal Medicine residency at the University of Alabama at Birmingham in 2009. She received her board certification in Internal Medicine in 2009.

She has a special interest in Preventive Medicine and nephrology/hypertension.

Dr. Khan resides with her family in League City.

Christi Lynn Wargo, CPNP-PC, is a board certified and Texas state licensed pediatric nurse practitioner. She provides care for pediatric patients in the department of Dermatology and General Academic Pediatrics at the Bay Colony and Galveston clinics. Christi graduated with her Associates in Nursing in 2001 from College of the Mainland and from there went on to the University of Texas Medical Branch, where she received her Bachelor's in Nursing in 2003 and then her Master's in Nursing for Pediatric Nurse Practitioner in 2008. She is currently enrolled once again in UTMB's School of Nursing for her Doctorate in Nursing Practice with plans to graduate in the Spring of 2022.

Prior to joining the dermatology department in October of 2016, Christi worked as a pediatric nurse practitioner for the Texas Children's Mobile Clinic, the FQHC Bell's Hill Community clinic in Waco, and she started the school-based Kruse clinic at Memorial Hermann Health Centers for Schools in Pasadena. In 2017, Christi started in the department of General Academic Pediatrics Bay Colony location on Wednesdays seeing primary care patients. She also occasionally provides care at the UTMB Pediatric After-Hours Urgent care clinic in League City. Christi has a great love of community and spends much of her free time volunteering both in Texas as well as abroad.

She is also currently serving on the board of the Houston Area Chapter of the National Association of Pediatric Nurse Practitioners as the Community Co-Chair and is Secretary for the Global Health Special Interest Group and member of the Pediatric Dermatology Special Interest Group. She is also a member of UTMB's Advanced Practice Providers Council. Christi is fluent in English and Spanish.

Dr. Xie joined the UTMB Health Department of Family Medicine in 2021. Dr. Xie earned her Bachelor of Science at the University of Texas at Dallas and her Doctorate of Osteopathic Medicine from the University of North Texas Health Science Center in Fort Worth, Texas. Dr. Xie completed her residency training from Baylor College of Medicine in Houston Texas and also served on the Texas Association of Family Physician's (TAFP) Resident Council. She is a board certified family physician and will be seeing patients at the Family Medicine Clinic - Island West.

Dr. Xie's clinical interests include patient mental wellbeing and also women's health. Dr. Xie is a member of Doctors for Change serving on the Mental Health Committee and the Anti-Human Trafficking Committee.

Dr. Thompson joined UTMB's Department of Family Medicine in 1972. Dr. Thompson became Chairman of the Department of Family Medicine in 1998. She attended medical school at UTMB and did an internship at St. Vincent's Hospital in New York City. Following her internship, she returned to Galveston and became one of the first graduates of the Family Medicine Residency program at UTMB. Dr. Thompson is board certified in Family Medicine by the American Board of Family Medicine. She also has added credentials in Geriatrics. Her interests include medical student education, resident education and medical history and ethics.

Dr. Thompson serves as our clinician lead for the Primary Care Medical Home designation by NCQA for our family medicine clinics.

 Provider is LGBTQIA+ Responsive

Dr. Mukaila Raji attended medical school at the University of Ife in Nigeria. He also completed his internal medicine residency at Washington Hospital Center in Washington, DC, USA, a Geriatric Fellowship at Duke University in Durham, NC, USA, and Master of Science Degree in pharmacology at the University of Alberta in Canada. Dr. Raji is board certified in Internal Medicine and Geriatrics. He is a tenured Professor and Director of Geriatric Medicine at the University of Texas Medical Branch in Galveston. He has published over 80 peer-reviewed articles, 80 research abstracts, and several book chapters in the areas of geriatric pharmacology, cognitive aging, and disability.

Dr. Raji is a recipient of the 2006 Sir William Osler Excellence in Clinical Teaching Award and has earned the Edgar Gnitzinger Distinguished Professorship in Aging. He is also listed in U.S. News & World Report Top Doctors in America and has been listed in Super Doctors®. Dr. Raji teaches medical students, residents, and geriatrics fellows and serves as attending faculty on the Acute Care for the Elders Unit, Geriatric Consults, and Geriatric Clinic Service.

Dr. Lem, as he is commonly known, is a Pediatric Infectious Diseases and Pediatric Hospital Medicine Physician whose clinical practice is focused on General Pediatric Inpatient Care, improving the efficiency and quality of care of children hospitalized with common, serious infections such as pneumonia and meningitis and the human immunodeficiency virus (HIV) disease. He received his medical degree from the Central America Health Science University, Belize.

He completed his residency in Pediatrics at Loyola University Medical Center, Maywood, Illinois. He went on to complete fellowship in Pediatric Infectious Disease at the University of Florida Health Science Center, Jacksonville. Upon completing his fellowship, he joined UTMB as an Assistant Professor in the Department of Pediatrics in 2008.