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Researcher Spotlights

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March 22, 2022
Researcher Spotlights – March 2022

Each month, Phoenix Children’s Research spotlights leading physicians and other clinical leaders for their work in the areas of Research, Education and/or Advocacy. For the month of March, we are spotlighting Deborah J. Tom, MD for her work in the field of Education and Kathleen van Leeuwen, MD, FACS, FAAP for her contributions to Research and Advocacy.


Deborah J. Tom, MD

Deborah J. Tom, MD, is a neonatologist and serves as Chair of Phoenix Children’s Medical Student Mentorship. Board certified in neonatal-perinatal medicine, Dr. Tom was drawn to neonatology because of her desire to be involved with families during this very special time of their lives, as well as to provide hope for families with premature and sick newborns. She enjoys all aspects of neonatology and has expertise in treating neonates with complex medical diagnoses.

Dr. Tom joined Phoenix Children’s medical staff in 1998 and the new Neonatology Division in 2020. She currently serves as Chair of the Credentials Committee and as a member of the Medical Executive Committee.

From 2013 to 2020, Dr. Tom served as Medical Director of Phoenix Children’s Neonatal Intensive Care Unit (NICU). Under her direction, the NICU earned recognition in U.S. News & World Report’s Best Children’s Hospitals as a national leader in neonatology. Phoenix Children’s program progressively ascended into the Top 50 – ranking #20 nationally for the 2020 - 2021 time period – based on excellent outcomes, high quality of care and patient safety.

Dr. Tom has a special interest in mentoring the next generation of physicians. To collaborate with local medical schools, Dr. Tom established the Medical Student Mentorship Program at Phoenix Children’s. This past academic year, Dr. Tom engaged more than 100 of our pediatricians in student-focused activities, like Dine with Docs, Lunch and Learns, Simulation Boot Camps and mentoring opportunities, connecting physicians and medical students to create hands-on experiences and help build networks for guidance. 

“I have had the pleasure of working with Dr. Deborah Tom for the past 15 years. During this time, Debbie has demonstrated exceptional commitment to her patients and trainees. Very rarely have I ever seen an individual with the combination of energy and passion that Debbie brings each and every day. It is a true privilege and honor to call her my friend and colleague. I know that our community is a better place because of her contributions.” – Gregory C. Martin, MD, Division Chief of Neonatology.

In 2021, Dr. Tom was nominated as one of Phoenix Children’s Clinical Excellence Teachers of the Year secondary to building the Medical Student Mentorship Program. In 2022, she was recognized as a Top Doctor in PHOENIX magazine in neonatal-perinatal medicine.

Dr. Tom loves working at Phoenix Children’s because she is able to provide family-centered care with a strong multispecialty and multidisciplinary team at a hospital that specializes in children.

When not at work, you can find Dr. Tom spending time with her family and dog, running, traveling and crafting. She’s married to a pediatric cardiologist at Phoenix Children’s, Dr. Todd Nowlen. They have four children — some of whom are following in their parents’ footsteps and going into the medical field.

More About Dr. Tom’s Research and Publications

Early in her career, Dr. Tom was the recipient of the National Institutes of Health K08 Training 5-year grant for her research on heme oxygenase and has presented and published in this area.

She is currently involved in quality improvement projects with Vermont Oxford Network (VON), a national neonatal collaborative, and has given multiple presentations about her work to continuously improve the quality of care provided in Phoenix Children’s NICUs. 



Kathleen van Leeuwen, MD, FACS, FAAP

Kathleen van Leeuwen, MD, FACS, FAAP, is an attending pediatric surgeon at Phoenix Children’s and has been practicing in Phoenix since 2005. She is board certified in pediatric surgery and general surgery, and is the current Chair of the Program Committee for the American Pediatric Surgery Association. 

As a healthcare advocate, one of Dr. van Leeuwen’s most notable accomplishments was the conceptualization and founding of the Center for Fetal Care, which pulls together a network of specialty care providers for families facing an uncertain or medically complex pregnancy. The team of surgeons, cardiologists, radiologists, neonatologists and other specialists, treat babies with congenital problems, providing nationally ranked multidisciplinary medical and surgical services and care coordination delivered with empathy and understanding. This approach ensures the smooth transition of infants to pediatric subspecialists. As co-director of the program, Dr. van Leeuwen creates an environment that allows every parent to be their child’s best advocate, even before they are born.

“Dr. van Leeuwen is an excellent surgeon and researcher. Not only does her kindness extend to her patients, but it also extends to her employees, colleagues and the community. She is actively engaged in doing outreach with families on the weekends and even connecting on a personal level with these parents, striving to make their lives better and the care they receive optimal. Being around her and seeing how she treats everyone, her generosity and compassion are very apparent.” – Erica Weidler Baimbridge, Research Associate at Phoenix Children’s Departments of Plastic Surgery and General Surgery.

Dr. van Leeuwen also serves as Medical Director of the Colorectal Program and Director of the Reproductive Anomalies & Differences of Sex Development (RA/DSD) Clinic at Phoenix Children’s. Her research interests in this area involve decision-making for babies, teens and young adults with cloaca and intersex conditions. A community advocate, she is frequently involved in outreach for children with DSD, colorectal issues and spina bifida.

For more than a decade, Dr. van Leeuwen has continuously been the recipient of NIH-funding. Her “lab” – which includes her long-time Phoenix Children’s collaborators: Erica Weidler Baimbridge; Reeti Chawla, MD; Gwen Grimsby, MD; and Janett Hernandez – focuses on clinical research and taking excellent care of these patients. As a group, they have published numerous papers on clinical management for DSD and continue to increase Phoenix Children’s national presence each year as a premier site for managing children and adolescents with DSD. Dr. van Leeuwen is a lecturer at the University of Arizona College of Medicine and makes sure medical students are up to date on these complex children. She is currently mentoring four students in clinical research.

As Phoenix Children’s expands, Dr. van Leeuwen is helping to prepare services at the Phoenix Children’s Hospital – East Valley Campus, opening in 2023.

“Kathy’s passion for the care of children is immense and obvious in everything she does. Her commitment to the development of critical programs, ranging from prenatal and fetal care diagnostics to the surgical correction of complex colorectal and genitourinary conditions, as well as clinical research, is an invaluable asset for Phoenix Children’s and the patients and families for whom we care. She is an outstanding surgeon and community advocate, someone we are very fortunate to have in the Phoenix Children’s Department of Surgery.” – Daniel Ostlie, MD, Surgeon-in-Chief and Chair of Surgery at Phoenix Children's.

Dr. van Leeuwen is a Phoenix native and is proud to support her local community. She is a first-generation college student, and her father emigrated from the Netherlands just after WWII. She went to Moon Valley High School and now lives in the East Valley. Dr. van Leeuwen completed medical school at Columbia in Manhattan, and general surgery and pediatric surgery training in Ann Arbor at the University of Michigan. She has three talented daughters and sings in an all-doctor rock band, Central Line. She is regularly named one of PHOENIX magazine’s Top Doctors.

More About Dr. van Leeuwen’s Research

Dr. van Leeuwen is active nationally in two multicenter consortiums for children with intersex and colorectal conditions: the DSD – Translational Research Network (TRN) and the Pediatric Colorectal and Pelvic Learning Consortium (PCPLC).

Having joined the DSD-TRN in 2014 when Dr. van Leeuwen was awarded an R01 subaward, she not only joined the national collaborative and contributed to the national registry but also continued to propel the DSD research forward with numerous investigator-initiated studies within and outside the network. In 2016, Dr. van Leeuwen received another R01 subaward to systematically evaluate the perceptions of stakeholders within DSD care on what is considered optimal care and then to develop research-based educational resources in order to promote resiliency among individuals affected by DSD. The DSD-TRN was awarded a second R01 in 2018 where Phoenix Children’s continues to be a proud partnering site, contributing to the national registry and improving lifelong outcomes of those with DSD.

Continuing to promote health and wellbeing, Dr. van Leeuwen is helping Phoenix Children’s become a premier site for DSD care, particularly for adolescents and reconstructive surgeries (Soursa-Johnson et al., 2021; Weidler et al., 2020). Furthermore, by joining the PCPLC, she is regularly collaborating with other centers to improve long-term outcomes for colorectal patients (Kastenberg et al., 2021).

Other areas of research focus include management pathways for malrotation, study of multidisciplinary teams and outcomes related to evidence-based pathways, assessment of burnout amongst surgical residents and fellows, and evaluation of assent by adolescents for surgical reconstructive procedures.

Research Publications

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