The best part about working with kids is that “I get to laugh every day,” said Ke-You (Yoyo) Zhang, MD, clinical assistant professor for pediatrics–gastroenterology and hepatology at Stanford Medicine in California.
Everyday life for them is a challenge.
Dealing with sick children is difficult. “But I think the difference between pediatrics and adults is despite how hard things get, children are the single most resilient people you’re ever going to meet,” she said.
Kids don’t always know they’re sick and they don’t act sick, even when they are. “Every day, I literally get on the floor, I get to play, I get to run around. And truly, I have fun every single day. I get excited to go to work. And I think that’s what makes work not feel like work,” said Dr. Zhang.
In an interview, she discussed the satisfaction of following patients throughout their care continuum and her research to reduce the likelihood of transplant rejection.
She also shared an inspirational story of one young patient who spent his life tied to an IV, and how a transplant exposed him to the normal joys of life, like swimming, going to camp and getting on a plane for the first time.
Q: Why did you choose this subspecialty of pediatric GI?
I think it’s the best subspecialty because I think it combines a lot of the things that I enjoy, which is long-term continuity of care. It’s about growing up with your patients and seeing them through all the various stages of their life, often meeting patients when they’re babies. I get pictures of high school graduations and life milestones and even see some of my patients have families of their own. Becoming a part of their family is very meaningful to me. I also like complexity and acuity, and gastroenterology and hepatology provide those things.
And then lastly, it’s great to be able to exercise procedural skills and constantly learn new procedural skills.
Q: How did you become interested in the field of pediatric intestinal and liver transplantation?
I did all my training here at Stanford. We have one of the largest pediatric transplant centers and we also have a very large intestinal rehabilitation population.
Coming through residency and fellowship, I had a lot of exposure to transplant and intestinal failure, intestinal rehabilitation. I really liked the longitudinal relationship I got to form with my patients. Sometimes they’re in the neonatal ICU, where you’re meeting them in their very first days of life. You follow them through their chronic illness, through transplant and after transplant for many years. You become not just their GI, but the center of their care.
Q: What challenges are unique to this type of transplant work?
Pediatric intestinal failure and intestinal transplant represents an incredibly small subset of children. Oftentimes, they do not get the resources and recognition on a national policy level or even at the hospital level that other gastrointestinal diseases receive. What’s difficult is they are such a small subset but their complexity and their needs are probably in the highest percentile. So that’s a really challenging combination to start with. And there’s only a few centers that specialize in doing intestinal rehabilitation and intestinal transplantation for children in the country.
Developing expertise has been slow. But I think in the last decade or so, our understanding and success with intestinal rehabilitation and intestinal transplantation has really improved, especially at large centers like Stanford. We’ve had a lot of success stories and have not had any graft loss since 2014.
Q: Are these transplants hard to acquire?
Yes, especially when you’re transplanting not just the intestines but the liver as well. You’re waiting for two organs, not just one organ. And on top of that, you’re waiting for an appropriately sized donor; usually a child who’s around the same size or same age who’s passed away. Those organs would have to be a good match. Children can wait multiple years for a transplant.
Q: Is there a success story you’d like to share?
One patient I met in the neonatal ICU had congenital short bowel syndrome. He was born with hardly any intestines. He developed complications of being on long-term intravenous nutrition, which included recurrent central line infections and liver disease. He was never able to eat because he really didn’t have a digestive system that could adequately absorb anything. He had a central line in one of his large veins, so he couldn’t go swimming.
He had to have special adaptive wear to even shower or bathe and couldn’t travel. It’s these types of patients that benefit so much from transplant. Putting any kid through transplant is a massive undertaking and it certainly has risks. But he underwent a successful transplant at the age of 8—not just an intestinal transplant, but a multi-visceral transplant of the liver, intestine, and pancreas. He’s 9 years old now, and no longer needs intravenous nutrition. He ate by mouth for the very first time after transplant. He’s trying all sorts of new foods and he was able to go to a special transplant camp for children. Getting on a plane to Los Angeles, which is where our transplant camp is, was a huge deal.
He was able to swim in the lake. He’s never been able to do that. And he wants to start doing sports this fall. This was really a life-changing story for him.
Q: What advancements lie ahead for this field of work? Have you work on any notable research?
I think our understanding of transplant immunology has really progressed, especially recently. That’s what part of my research is about—using novel therapies to modulate the immune system of pediatric transplant recipients. The No. 1 complication that occurs after intestinal transplant is rejection because obviously you’re implanting somebody else’s organs into a patient.
I am involved in a clinical trial that’s looking at the use of extracellular vesicles that are isolated from hematopoietic stem cells. These vesicles contain various growth factors, anti-inflammatory proteins and tissue repair factors that we are infusing into intestinal transplant patients with the aim to repair the intestinal tissue patients are rejecting.
Q: When you’re not being a GI, how do you spend your free weekend afternoons?
My husband and I have an almost 2-year-old little girl. She keeps us busy and I spend my afternoons chasing after a crazy toddler.
Lightning Round
Texting or talking?
Huge texter
Favorite junk food?
French fries
Cat or dog person?
Dog
Favorite ice cream?
Strawberry
If you weren’t a gastroenterologist, what would you be?Florist
Best place you’ve traveled to?
Thailand
Number of cups of coffee you drink per day?
Too many
Favorite city in the US besides the one you live in?
New York City
Favorite sport?
Tennis
Optimist or pessimist?
Optimist
Summary content
7 Key Takeaways
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Developed a paper-based colorimetric sensor array for chemical threat detection.
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Can detect 12 chemical agents, including industrial toxins.
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Production cost is under 20 cents per chip.
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Utilizes dye-loaded silica particles on self-adhesive paper.
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Provides rapid, simultaneous identification through image analysis.
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Inspired by the mammalian olfactory system for pattern recognition.
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Future developments include a machine learning-enabled reader device.
The guidelines emphasize four-hour gastric emptying studies over two-hour testing. How do you see this affecting diagnostic workflows in practice?
Dr. Staller: Moving to a four-hour solid-meal scintigraphy will actually simplify decision-making. The two-hour reads miss a meaningful proportion of delayed emptying; standardizing on four hours reduces false negatives and the “maybe gastroparesis” purgatory that leads to repeat testing. Practically, it means closer coordination with nuclear medicine (longer slots, consistent standardized meal), updating order sets to default to a four-hour protocol, and educating front-line teams so patients arrive appropriately prepped. The payoff is fewer equivocal studies and more confident treatment plans.
Metoclopramide and erythromycin are the only agents conditionally recommended for initial therapy. How does this align with what is being currently prescribed?
Dr. Staller: This largely mirrors real-world practice. Metoclopramide remains the only FDA-approved prokinetic for gastroparesis, and short “pulsed” erythromycin courses are familiar to many of us—recognizing tachyphylaxis limits durability. Our recommendation is “conditional” because the underlying evidence is modest and patient responses are heterogeneous, but it formalizes what many clinicians already do: start with metoclopramide (lowest effective dose, limited duration, counsel on neurologic adverse effects) and reserve erythromycin for targeted use (exacerbations, bridging).
Several agents, including domperidone and prucalopride, received recommendations against first-line use. How will that influence discussions with patients who ask about these therapies?
Dr. Staller: Two points I share with patients: evidence and access/safety. For domperidone, the data quality is mixed, and US access is through an FDA IND mechanism; you’re committing patients to EKG monitoring and a non-trivial administrative lift. For prucalopride, the gastroparesis-specific evidence isn’t strong enough yet to justify first-line use. So, our stance is not “never,” it’s just “not first.” If someone fails or cannot tolerate initial therapy, we can revisit these options through shared decision-making, setting expectations about benefit, monitoring, and off-label use. The guideline language helps clinicians have a transparent, evidence-based conversation at the first visit.
The guidelines suggest reserving procedures like G-POEM and gastric electrical stimulation for refractory cases. In your practice, how do you decide when a patient is “refractory” to medical therapy?
Dr. Staller: I define “refractory” with three anchors.
1. Adequate trials of foundational care: dietary optimization and glycemic control; an antiemetic; and at least one prokinetic at appropriate dose/duration (with intolerance documented if stopped early).
2. Persistent, function-limiting symptoms: ongoing nausea/vomiting, weight loss, dehydration, ER visits/hospitalizations, or malnutrition despite the above—ideally tracked with a validated instrument (e.g., GCSI) plus nutritional metrics.
3. Objective correlation: delayed emptying on a standardized 4-hour solid-meal study that aligns with the clinical picture (and medications that slow emptying addressed).
At that point, referral to a center with procedural expertise for G-POEM or consideration of gastric electrical stimulation becomes appropriate, with multidisciplinary evaluation (GI, nutrition, psychology, and, when needed, surgery).
What role do you see dietary modification and glycemic control playing alongside pharmacologic therapy in light of these recommendations?
Dr. Staller: They’re the bedrock. A small-particle, lower-fat, calorie-dense diet—often leaning on nutrient-rich liquids—can meaningfully reduce symptom burden. Partnering with dietitians early pays dividends. For diabetes, tighter glycemic control can improve gastric emptying and symptoms; I explicitly review medications that can slow emptying (e.g., opioids; consider timing/necessity of GLP-1 receptor agonists) and encourage continuous glucose monitor-informed adjustments. Pharmacotherapy sits on top of those pillars; without them, medications will likely underperform.
The guideline notes “considerable unmet need” in gastroparesis treatment. Where do you think future therapies or research are most urgently needed?
Dr. Staller: I see three major areas.
1. Truly durable prokinetics: agents that improve emptying and symptoms over months, with better safety than legacy options (e.g., next-gen motilin/ghrelin agonists, better-studied 5-HT4 strategies).
2. Endotyping and biomarkers: we need to stop treating all gastroparesis as one disease. Clinical, physiologic, and microbiome/omic signatures that predict who benefits from which therapy (drug vs G-POEM vs GES) would transform care.
3. Patient-centered trials: larger, longer RCTs that prioritize validated symptom and quality-of-life outcomes, include nutritional endpoints, and reflect real-world medication confounders.
Our guideline intentionally highlights these gaps to hopefully catalyze better trials and smarter referral pathways.
Dr. Staller is with the Division of Gastroenterology, Massachusetts General Hospital and Harvard Medical School, Boston.