We are excited to welcome the exceptional physicians joining our WashU Nephrology Fellowship Program for 2025-2027. Each brings a unique talent, passion and commitment to the field of nephrology and to our division.
Catey Ashlyn Abbott, DO
“Witnessing firsthand the complex decisions patients face regarding their care – particularly in critical settings – highlights the importance of respecting and supporting their right to make informed choices about their health.”
A proud Arkansan, Catey earned her medical degree as part of the inaugural graduating class at the Arkansas College of Osteopathic Medicine. She went on to complete her internal medicine residency at the University of Arkansas in Fayetteville, where she served as Chief Resident. Known for her open-door leadership style, she fostered a supportive environment that allowed residents to voice concerns, ensuring their perspectives were heard and respected.
As Chief Resident, Catey introduced the “House Cup,” which boosted volunteerism by 500% among residents and fostered healthy competition. Through regular teaching conferences and mentorship of junior trainees, she helped strengthen their program’s educational culture and created an environment that supported professional growth. She was twice honored with the Resident Teaching Award in recognition of her passion for mentorship and educating future physicians.
Following residency, Catey served as a hospitalist in both urban and rural Arkansas communities, where she honed her skills as a compassionate internist and discovered her passion for advancing kidney health.
“It’s been deeply rewarding to care for patients and their families in both settings. I have developed a special affinity for nephrology cases, finding immense satisfaction in managing their complex medical needs while building meaningful relationships with them and their loved ones. These experiences have strengthened my commitment to pursuing nephrology as a specialty and deepened my resolve to make a positive impact on patient care.”
She has presented original research on topics such as tianeptine abuse (Gas Station Heroin) and constrictive pericarditis at regional conferences, and was co-author of the article “Anaphylaxis in Alpha-Gal patients treated with F(ab) for snake bite venom,” published in Toxicology Communication, July 2024.
Catey moved to St. Louis as part of a “couples match” with her fiancé, Dr. Christian Ratzlaff, who is starting a fellowship in the Division of Infectious Diseases here at WashU.
In her spare time, Catey enjoys CrossFit, biking, reading for pleasure, cheering on the Razorbacks and Dallas Cowboys, and making recipes with healthy substitutions. During her residency, she made it her mission to make all of the The Defined Dish meals, a popular food and lifestyle brand created by Alex Snodgrass, a recipe developer and New York Times bestselling author.
In addition, she and Christian enjoy time a new member of their household – adopted dog, Chip, an adorable Bernedoodle.
Jacob Lambertsen, MD
“Hard work was instilled in me at a young age. I quickly learned hard work may get results, but curiosity makes them meaningful.”
Jacob graduated summa cum laude from Southern Utah University with a degree in biology and chemistry and the high honor of being valedictorian for the College of Science and Engineering. He went on to earn his medical degree from Wright State University Boonshoft School of Medicine before completing his residency in internal medicine at Atrium Health Wake Forest Baptist. Along the way, Jacob received numerous honors, including the Merck Manual Award for Academic Excellence and the Southern Utah University Scholar of the Year award.
Early on, Jacob was confident about his professional goals. “I aimed to pursue medical education and basic science research knowing my background in analytical chemistry allowed me to see the fascinating logic behind renal physiology and pathophysiology. This complemented two of my passions: learning and teaching.”
With an interest in basic research, in medical school he took on a nuclear magnetic resonance (NMR) spectroscopy project to identify characteristic fecal metabolomic patterns that indicated toxicant ingestion. During residency, he continued this interest with an NMR study looking to identify metabolomic variations in head and neck cancer lineages that helped explain radiation resistance.
Equally passionate about teaching, Jacob developed and led educational initiatives for both peers and patients. He developed a 40-hour interviewing curriculum for first-year medical students at Wright State University and actively contributed to medical education efforts at Atrium Health Wake Forest Baptist.
Jacob is also deeply interested in patient education and rural outreach. He completed the rural education pathway in medical school where he assisted with quality improvement projects looking at improving medical adherence through increasing health literacy via patient education.
“Raised in a medically underserved area, I have witnessed the need for patient advocacy. I aim to enhance specialty access in these communities and deliver excellent care while empowering patients through education.”
Beyond medicine, Jacob is committed to community service. As a volunteer at the Dayton Food Bank, he assisted with food distribution and community gardening. He has contributed to philanthropic efforts at the Huntsman Cancer Institute, helping raise over $80,000 for cancer research.
An avid outdoorsman, Jacob enjoys hiking, fishing, and snowboarding, horseback riding, camping, ATV riding, and birding. He’s a reader of historical fiction, non-fiction and fantasy, and is keen on learning new piano scores after six years of lessons. In the kitchen, he takes up the challenge of creating recipes from his homegrown produce.
Jacob is a firm believer that “hard work, curiosity, self-reflection, and community can transform stressful situations into joyful opportunities.”
Meng Hsun Lee, MD
“As a student, math and physics were my favorite subjects, captivating me with their logical structure and the challenge of solving intricate problems.”
Meng Hsun earned his medical degree from National Cheng Kung University College of Medicine in Taiwan and completed his residency in internal medicine at Maimonides Medical Center in Brooklyn, NY.
Meng Hsun’s grandparents, who played a major role in his upbringing, also played a pivotal role in inspiring his pursuit of medicine, as he witnessed both of them endure the challenges of end-stage renal disease. “Their resilience, coupled with my family’s steady support, shaped my desire to provide compassionate care for patients facing similar challenges.”
Drawn to logic and problem-solving from a young age, Meng Hsun found early inspiration in math and physics—passions that evolved into a fascination with human physiology and complex clinical reasoning. Internal medicine deepened his interest in electrolyte and acid-base disturbances, where intellectual precision and procedural skill intersected to improve outcomes. These experiences solidified his calling to nephrology.
Reflecting his strong interest in research, Meng Hsun has built an impressive research portfolio that includes retrospective observational studies, meta-analyses. “Through my research experience, I learned that research is not just about solving clinical questions but also about continuous learning and updating knowledge. Conducting research encouraged me to study more deeply and think critically, making me a more informed and thoughtful practitioner.”
Prior to starting his residency, Meng Hsun spent several months traveling in central America. The experience deepened his cultural understanding and strengthened his language skills. “It broadened my horizons and motivated me to continue learning. Knowing Spanish has opened new doors, enhancing my ability to communicate with a broader patient population and deepening my cultural competence.”
In his down time, Meng Hsun enjoys backpacking, photography, cycling, table tennis and watching baseball.
Bibi Shazeeda Razak, MD
“My journey has taught me the importance of resilience, empathy, and continuous learning.”
Bibi earned her medical degree from Texila American University in Guyana followed by a master’s degree in biomedical science at the Icahn School of Medicine at Mount Sinai in New York City. She then went on to complete her residency in internal medicine at Richmond University Medical Center (RUMC) in Staten Island, NY.
As a fellow, Bibi brings with her a strong foundation in both clinical medicine and academic research. Through her work in inpatient and outpatient settings within a busy community program, she quickly recognized the importance of efficient, effective, and collegial teamwork in providing acute patient care. She was actively involved in quality improvement initiatives and served on the Patient Experience Committee at RUMC, focusing on enhancing quality of care and promoting a patient-centered approach.
Bibi’s master’s degree in clinical research equipped her a solid framework for applying evidence-based medicine in clinical practice. Her research contributions include published and submitted articles addressing topics such as kidney injury, cardiogenic shock, and disparities in atrial fibrillation hospitalizations.
A passionate educator teaching and mentor, Bibi participated in MedStart and MedDOCS – programs designed to inspire and support for New York City middle and high school students. “Our goal was to provide these students with mentorship and excite them about pursuing education/careers in science and medicine.”
She also served as a Near-Peer Mentor in the Masters in Clinical Research Program and volunteered at The College Student Pantry, a food assistance initiative serving college and graduate students in NYC.
“My teaching experience was deeply meaningful because it allowed me to positively impact students’ lives through mentorship and guidance, serve as a role model, foster collaboration among peers, and contribute to a cohesive and supportive academic community.”
Outside of work, Bibi enjoys cricket, cycling, and is devoted advocate for animal welfare who is especially fond of cats!
Hoang “Anh” Tang, DO
“The constant search for an answer, whether it be for the pathophysiology of crystalline nephropathy or the reason why your young patient has acute renal failure is not only engaging but also fulfilling.”
Anh earned a master’s degree in biomedical science from UNT Health Science Center at Fort Worth, Fort Worth, TX, before completing her medical degree from Des Moines University College of Osteopathic Medicine in Iowa. She completed her residency in internal medicine at MercyOne Des Moines/PHC Consortium in Des Moines, where she served as Chief Resident.
During residency, Anh distinguished herself as a dedicated leader and educator. As chief resident, she led quality improvement initiatives, mentored junior residents, and enhanced medical education by coordinating lectures and launching peer engagement programs, including polling-based board reviews and peer support sessions. Her passion for teaching began long before residency, with early experiences tutoring math students and guiding new interns through the complexities of hospital workflow.
She believes that one of the biggest shortcomings of modern medical practice is the lack of accessible patient education. “I feel that having a positive impact on patients’ understanding of their diagnoses and treatments ultimately has a positive impact on their outcomes.” Looking ahead, she hopes to use her training to build the clinical expertise necessary to be an effective teacher – not just to patients, but also for medical students, residents, and colleagues throughout her career.
Actively involved in community health outreach programs, Ahn led health fairs through the Asian and Pacific American Medical Student Association (APAMSA), volunteered at a local animal rescue league, and as a Continuity Clinic Resident at the Primary Healthcare Clinic (PHC) in De Moines, advocated for immigrant healthcare access. “The PHC is a nonprofit clinic whose goal is to treat primarily the underserved and expand our reach to new immigrants who might otherwise delay healthcare when arriving to America.” In recognition for her contributions, she received the Excellence in Primary Healthcare Award in 2024.
Adding to the many reasons Anh is drawn to nephrology, she simply says, “I love talking about sodium.”
Outside of work, Anh is an avid reader of psychological thriller and mystery novels, collecting Pokémon cards (especially rate, illustrated cards), cooking and baking, and unwinding with her dog … who, impressively, has learned how to dance!
Kevser Akyuz Yesilyaprak, MD
“[I] found my calling in medicine, where I now solve the riddles of the human body. By understanding pathophysiology, synthesizing symptoms, lab and imaging findings, I bring together the pieces of each patient’s condition, witnessing their stories and contributing to their well-being.”
Kevser earned her medical degree with honors from Istanbul University Cerrahpasa Faculty of Medicine in Turkey. She advanced her education as a Clinical Research Fellow at Cleveland Clinic Foundation Heart and Vascular Institute, then completed her internal medicine residency at Wayne State University Ascension Providence Rochester Hospital in Michigan. Following residency, she served as an Academic Hospitalist at the Medical College of Wisconsin before serving as an Assistant Professor and Academic Hospitalist at SSM Health Saint Louis University Hospital.
Kevser discovered her passion for problem-solving at an early age, originally drawn to archaeology before finding her calling in medicine. That investigative drive led her to build a strong background in research, clinical medicine, and academic teaching. Her impressive list of publications in prestigious journals focus on topics such as tricuspid regurgitation, recurrent pericarditis and rare medical conditions. She has presented her work at various national and international conferences.
As a member of the educational initiative DART (Developing Academic and Research Teaching) program – designed for residents interested in enhancing their educational skills – Kevser participated in academic BootCamp sessions and designed and carried out a medical education project (the Intern Orientation Medical Education Project). She also participated in several volunteer activities including the Whitetulip Health Foundation, which provides support and mentorship for international medical graduates as they navigate the U.S. healthcare system, and she was project leader for the WSU IM Residency/Intern Orientation Medical Education Project, which is designed at easing the transition of international medical interns into their new roles as resident physicians.
Observing the profound impact of preventive medicine and patient education, where even brief teaching sessions can prevent major complications in patients with chronic kidney disease, Kevsar says, “Witnessing the happiness and gratitude in my patients’ faces as they gain a better understanding of their condition is a deeply rewarding aspect of medicine that I hope to cherish throughout my career.”
Outside of work, Kevser enjoys cooking, gardening, and walking with her cats.
