Paul Henderson

• MBChB, MRCPCH, PhD
• Consultant at University of Edinburgh

Background There are scarce data available on upadacitinib in children with Crohn's disease (CD). Aim To evaluate the effectiveness and safety of upadacitinib as an induction therapy in paediatric CD. Methods This was a multicentre retrospective study between 2022 and 2024 of children treated with upadacitinib for induction of remission of active...

Background Oral vancomycin has had limited use in paediatric Inflammatory Bowel Disease (PIBD), with reported efficacy in primary sclerosing cholangitis (PSC-PIBD)1, acute severe colitis as part of a quadruple antibiotic regimen2, and very early onset IBD3. This study evaluates its effectiveness and safety as single-agent therapy in non-PSC PIBD pa...

Background Data on upadacitinib therapy in children with Crohn’s disease (CD) are scarce. We aimed to evaluate the effectiveness and safety of upadacitinib as an induction therapy in pediatric CD. Methods A multicenter retrospective study of children treated with upadacitinib for the induction of remission of active CD from 30 centers worldwide af...

Pancreatitis, a condition characterised by inflammation of the pancreas, has multiple aetiologies. Improving clinical proficiency in prompt diagnosis and effective management leads to better outcomes for children with acute pancreatitis, acute recurrent pancreatitis and chronic pancreatitis. Establishing consensus guidance via the British Society o...

Objectives The aim of our study was to assess the effectiveness and side‐effect profile of a combination of azithromycin and metronidazole (CD AZCRO) as alternative induction therapy for 8 weeks in mild to moderately active paediatric Crohn's disease (CD). Methods We performed a retrospective cohort study (November 2012 to July 2023) of a regional...

Activating autophagy may be therapeutically beneficial, and we have previously shown that azathioprine (AZA), an immunomodulatory drug, induces autophagy. Here, we evaluated the induction of autophagy by the thiopurines AZA, mercaptopurine (6-MP) and thioguanine (6-TG) in THP-1 macrophages and investigated the mechanism of action in the context of...

We present a case of an 8‐week‐old infant with acute bloody diarrhoea and subsequent passage of an intestinal cast. An extensive immune and infection work‐up did not reveal a causative aetiology. Histopathology indicated the cast represented an intestinal pseudomembrane. 16S bacterial polymersae chain reaction of the pathology specimen was negative...

Background Exclusive enteral nutrition (EEN) is a main therapy for active Crohn’s disease (CD) in children, but normalisation of faecal calprotectin (FCAL) varies among patients, even in those who enter clinical remission. To better understand disease characteristics related to EEN efficacy and its mechanism of action, we compared clinical and micr...

Introduction Jejunal tube feeding (JTF) is used to deliver post-pyloric nutrition in children for a variety of indications such as reflux, foregut dysmotility and in anatomical or post-surgical gastrointestinal tract obstruction. It can be used to effectively deliver feeds, improve quality of life and may reduce the requirement for parenteral nutri...

Real-world data regarding subcutaneous infliximab (SC-IFX) in paediatric IBD (PIBD) patients is scarce. Our aim was to assess the feasibility of a switching program from intravenous infliximab (IV-IFX) to SC-IFX as maintenance in selected PIBD patients.We analysed a prospectively-identified, single regional centre, cohort of PIBD patients who were...

Recurrent acute and chronic pancreatitis remain rare in children and young people but can lead to significant morbidity with regard to significant pain, nutritional compromise, frequent hospital admissions, reduced quality of life. Total pancreatectomy (TP) can be performed to control pain and reduce complications, however insulin-dependent ‘brittl...

Background Faecal calprotectin (FCAL) rises rapidly in children with Crohn’s disease (CD) following treatment with exclusive enteral nutrition (EEN). We aimed to identify clinical, dietary and diet-related microbial metabolites which associate with the recurrence of FCAL above 250 mg/kg after 21 days of food reintroduction. Methods Children with C...

Paediatric inflammatory bowel disease (PIBD) incidence and prevalence is increasing worldwide. Robust epidemiology can inform new aetiological hypothesis, inform healthcare provision and improve patient outcomes. The last prospective United Kingdom (UK) PIBD incidence study was performed in 1999 (5.2/100,000/yr); we aimed to update this incidence d...

OBJECTIVES This study described disease characteristics and long-term outcomes in patients diagnosed with very early onset inflammatory bowel disease (VEOIBD) (diagnosed before 6 years of age) and infantile-IBD (before 2 years). METHODS Cases from 21 centers worldwide diagnosed with VEOIBD (2008–2018), with minimum 2 years of follow-up, were retro...

LINKED CONTENT This article is linked to Malham et al papers. To view these articles, visit https://doi.org/10.1111/apt.17994 and https://doi.org/10.1111/apt.18026.

Background Faecal calprotectin (FCAL) rises rapidly in children with Crohn’s disease (CD) following treatment with exclusive enteral nutrition (EEN). We aimed to identify clinical, dietary and diet-related microbial metabolites which associate with the recurrence of FCAL above 250 mg/kg after 21 days of food reintroduction. Methods Children with C...

Background Exclusive enteral nutrition (EEN) is a main therapy for active Crohn’s disease (CD) in children, but normalisation of faecal calprotectin (FCAL) varies among patients, even in those who enter clinical remission. To better understand disease characteristics related to EEN efficacy and its mechanism of action, we compared clinical and micr...

Background Paediatric inflammatory bowel disease (PIBD) incidence and prevalence is increasing worldwide. Robust epidemiology can inform new aetiological hypothesis, inform healthcare provision and improve patient outcomes. The last prospective United Kingdom (UK) PIBD incidence study was performed in 1999 (5.2/100,000/yr); we aimed to update this...

Background & Aims Treatment guidelines for paediatric Crohn’s disease (CD) suggest early use of anti-tumour necrosis factor alpha (anti-TNF) in high-risk individuals. The aim is to evaluate the effect of early anti-TNF in a real-world cohort. Methods Children with newly-diagnosed CD were prospectively recruited at 28 participating sites of the int...

Background: Exclusive enteral nutrition (EEN) is the recommended first-line induction treatment in pediatric patients with active luminal Crohn's disease (CD). We aimed to provide a nationwide overview of evolving EEN practices during an era of increasing biologic use. Methods: We analyzed a prospectively identified nationwide cohort of newly di...

Paediatric inflammatory bowel disease (PIBD; which encompasses Crohn’s disease (CD), ulcerative colitis (UC) and IBD-unclassified (IBD-U)) has an increased overall risk of mortality and malignancy compared to the general population however this is not fully characterized in children. Scotland has a population of 5.5 million people and one of the hi...

Background and aims: Ulcerative proctitis (UP) is an uncommon presentation in paediatric patients with ulcerative colitis. We aimed to characterize the clinical features and natural history of UP in children, and identify predictors of poor outcomes. Methods: Retrospective study involving 37 sites affiliated with the IBD Porto Group of ESPGHAN....

No real-world data are available on subcutaneous infliximab (SC-IFX) in paediatric inflammatory bowel disease (PIBD). We report a single-centre cohort experience of an elective switching program from biosimilar intravenous infliximab (IV-IFX) to SC-IFX, 120mg fortnightly, as maintenance. Clinical and laboratory data were collected for 7 patients wi...

An outbreak of acute hepatitis of unknown aetiology in children was reported in Scotland in April 20221 and has now been identified in 35 countries2. Several recent studies have suggested an association with human adenovirus (HAdV), a virus not commonly associated with hepatitis. Here we report a detailed case-control investigation and find an asso...

Background Treatment with the CD-TREAT solid food diet improves disease activity indices, faecal calprotectin (FCAL) levels and quality of life in adults and children with active Crohn’s disease (CD); particularly in patients who adhere to the diet. Here we describe changes in faecal microbiome parameters during therapy with CD-TREAT and explore th...

Background Ulcerative proctitis (UP) is an uncommon presentation in paediatric patients with ulcerative colitis, accounting for <10% of cases. Here we aimed to characterize the clinical features and natural history of paediatric patients with UP, and to identify predictors of poor outcomes. Methods A retrospective cohort study involving 37 sites a...

Background Anti-TNF drugs, such as infliximab, are associated with attenuated antibody responses after SARS-CoV-2 vaccination. We aimed to determine how the anti-TNF drug infliximab and the anti-integrin drug vedolizumab affect vaccine-induced neutralising antibodies against highly transmissible omicron (B.1.1.529) BA.1, and BA.4 and BA.5 (hereafte...

Background The use of biologics in paediatric‐onset inflammatory bowel disease (PIBD) is rapidly changing. Aims To identify the incidence and prevalence of biologic use within Scottish PIBD services and to describe patient demographics and outcomes for those patients who required escalation of therapy beyond anti‐tumour necrosis factor alpha biolo...

Background and Aims Exclusive enteral nutrition (EEN) is the recommended induction treatment of mild to moderate active paediatric Crohn’s Disease (CD). This study compared outcomes of two proprietary polymeric formulas. Treatment effectiveness was examined along with practical aspects of formula delivery and differences in estimated treatment cost...

Background Anti‐drug antibodies are associated with treatment failure to anti‐TNF agents in patients with inflammatory bowel disease (IBD). Aim To assess whether immunogenicity to a patient's first anti‐TNF agent would be associated with immunogenicity to their second, irrespective of drug sequence Methods We conducted a UK‐wide, multicentre, ret...

LINKED CONTENT This article is linked to Malmborg et al papers. To view these articles, visit https://doi.org/10.1111/apt.17148

Unlabelled: Autoimmune hepatitis (AIH) is a rare, but potentially severe, cause of liver disease in children. We aimed to summarize how children with AIH in Scotland presented, were investigated and managed in addition to producing novel epidemiological data and outcomes. Methods: All prevalent pediatric patients with AIH cared for in pediatric...

paragraph An outbreak of acute hepatitis of unknown aetiology in children was first reported in Scotland in April 2022. ¹ Cases aged <16 years have since been identified in 35 countries. ² Here we report a detailed investigation of 9 early cases and 58 control subjects. Using next-generation sequencing and real-time PCR, adeno-associated virus 2 (A...

Aim: Advances in paediatric hepatology have led to the increasing survival of patients with paediatric-onset chronic hepatobiliary disease into adulthood. Data are lacking with regard to the outcomes of this heterogeneous group of patients and current transition models may be insufficient. This retrospective regional cohort study examined the outc...

Objective It is unclear how the compounding prevalence of inflammatory bowel disease (IBD) has translated into the causes and rates of hospitalisation, particularly in an era of increased biologic prescribing. We aimed to analyse these trends in a population‐based IBD cohort over the last 10 years. Design The Lothian IBD registry is a complete, va...

Background: Exclusive enteral nutrition (EEN) is the recommended induction treatment of mild to moderate active pediatric Crohn's disease (CD). This study compared outcomes of 2 proprietary polymeric formulas. Treatment effectiveness was examined along with practical aspects of formula delivery and differences in estimated treatment costs. Method...

Background and Aims The incidence of paediatric-onset inflammatory bowel disease (PIBD) continues to rise globally. We aimed to determine whether mode of delivery, gestational age at birth, or type of infant feeding contribute to the development of PIBD in a nationwide cohort of Scottish children. Methods All children born in Scotland between 1981...

Anti tumour necrosis factor (anti-TNF) drugs increase the risk of serious respiratory infection and impair protective immunity following pneumococcal and influenza vaccination. Here we report SARS-CoV-2 vaccine-induced immune responses and breakthrough infections in patients with inflammatory bowel disease, who are treated either with the anti-TNF...

Background Very early-onset inflammatory bowel disease (VEOIBD) is diagnosed before the age of 6 years while infantile IBD occurs before the age of 2 years. We aimed to assess disease characteristics and long-term outcomes in these populations. Methods We conducted a retrospective longitudinal cohort study in 21 pediatric centers worldwide. Patien...

Background Exclusive enteral nutrition (EEN) is an established induction treatment for active Crohn’s disease (CD) with a proposed mechanism of action involving the gut microbiome. We have previously shown that CD-TREAT diet, a food-based diet with similar dietary profile to EEN, improves rat ileitis and replicates the effect of EEN on the gut micr...

Background Recent, albeit limited, studies indicate that combination oral antibiotic therapy may be an efficacious, immunosuppressive-free, alternative strategy to achieve remission in a subset of medically refractory IBD patients. We sought to identify incidence data and provide cohort analysis of any refractory IBD patients who subsequently respo...

Background & Aims The incidence of inflammatory bowel disease (IBD) is increasing internationally, particularly in nations with historically low rates. Previous reports of the epidemiology of pediatric-onset IBD identified a paucity of data. We systematically reviewed the global trends in incidence and prevalence of IBD diagnosed <21 years over the...

The combined impact of common and rare exonic variants in COVID-19 host genetics is currently insufficiently understood. Here, common and rare variants from whole-exome sequencing data of about 4000 SARS-CoV-2-positive individuals were used to define an interpretable machine-learning model for predicting COVID-19 severity. First, variants were conv...

Introduction Fatigue is one of the most common symptoms in IBD resulting in decreased quality of life, impaired work productivity, and higher societal costs. However, little is known about its etiology and pathophysiology. We aimed to estimate the prevalence of fatigue and to identify predictive factors for fatigue. Methods The PREdiCCt study is t...

Evidence-based guidelines have been developed outlining the concomitant use of anti-tumor necrosis factor alpha (anti-TNF) agents and immunomodulators including azathioprine (AZA) and methotrexate (MTX) in both adult and pediatric populations. However, there exists a paucity of data guiding evidence-based strategies for their withdrawal in pediatri...

Fissuring perianal Crohn disease (CD) is not recognised as a perianal phenotype in Montreal/Paris inflammatory bowel disease classifications; however, can occasionally present as complicated disease with severe perianal pain driving increasingly intensive medical therapy despite well controlled luminal disease. We identified a regional cohort of pr...

Background The incidence of inflammatory bowel disease (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC), is increasing internationally, particularly in developing nations where rates were historically low. Previous reports of the incidence and prevalence of pediatric-onset IBD have identified a paucity of population-based studies....

Objectives: To assess current practices around the use of combination immunosuppression in paediatric inflammatory bowel disease (PIBD) with a focus on the subsequent withdrawal process. Methods: A web-based, 43 question survey. Results: Surveys were completed by 70 paediatric gastroenterologists (PG) from 27 nations across Europe, North Ameri...

Introduction: Thetanix (gastroresistant capsules containing lyophilized Bacteroides thetaiotaomicron) is a live biotherapeutic, under development for Crohn's disease, that antagonizes transcription factor nuclear factor kappa B, reducing proinflammatory cytokines, particularly tumor necrosis factor alpha. We aimed to assess safety and tolerability...

Objective: We aimed to provide an evidence-supported update of the ECCO-ESPGHAN guideline on the medical management of paediatric Crohn's disease [CD]. Methods: We formed 10 working groups and formulated 17 PICO-structured clinical questions [Patients, Intervention, Comparator, and Outcome]. A systematic literature search from January 1, 1991 to...

Paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) is a newly described condition. It has a spectrum of presentations proposed to occur as part of a post-infectious immune response. We report the first case of PIMS-TS in a child on established anti-Tumor Necrosis Factor-alpha (anti-TNF-α) therapy; a 10 year...

The prevalence of inflammatory bowel disease (IBD) continues to rise globally, however the true proportion of paediatric IBD patients remains unknown. We conducted an all-age, multiparameter, population-based search using capture-recapture methodology to identify all IBD cases to 31/08/2018 within Lothian, a defined health board and the largest of...

Paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) is a newly described condition. It has a spectrum of presentations related to hyperinflammation and cytokine storm. We report the first case of PIMS-TS in a child on established anti-Tumor Necrosis Factor-alpha (anti-TNF-α) therapy; a 10 year-old girl with...

Background The incidence of paediatric-onset inflammatory bowel disease (PIBD) continues to rise, with genetic-environmental interactions expected to play a vital role. Given gestation and infancy are sensitive periods for environmental change, we aimed to determine whether a mode of delivery, gestational age or type of infant feeding contribute to...

Background The risk of morbidity and mortality related to paediatric-onset inflammatory bowel disease (PIBD) and its treatment is a major concern to both patients and clinicians, especially when this may affect early adult life. We aimed to determine whether PIBD patients are at increased risk of ischaemic heart disease (IHD), stroke, cancer and de...

Background The use of biologics in paediatric inflammatory bowel disease (PIBD) is rapidly changing with the introduction of new mode of action medications, cheaper biosimilar alternatives, improved convenience with home care options and an increasing focus on early intensified management. No nationwide paediatric data is available to objectively c...

Crohn Disease (CD) is a complex genetic disorder for which more than 140 genes have been identified using genome wide association studies (GWAS). However, the genetic architecture of the trait remains largely unknown. The recent development of machine learning (ML) approaches incited us to apply them to classify healthy and diseased people accordin...

Objective IBD prevalence is estimated to be rising, but no detailed, recent UK data are available. The last reported prevalence estimate in the UK was 0.40% in 2003. We aimed to establish the current, and project future, prevalence in Lothian, Scotland. Design We conducted an all-age multiparameter search strategy using inpatient IBD international...

Objectives: Stricturing duodenal Crohn's disease (CD) is a rare but serious presentation of CD causing significant morbidity. We aim to provide the first robust incidence data and case studies on this severe presentation in children. Methods: A regional cohort of prospectively acquired incident cases of paediatric CD diagnosed <16 years of age i...

Background A recent systematic review reports an overall prevalence for IBD of 0.3% in Western countries¹ but there are no UK estimates since 2003. We aimed to report current all-age prevalence, healthcare usage and forecast 2028 caseload, for IBD in Lothian. Methods We conducted an extensive capture-recapture search strategy, manually confirming...

Introduction and objectives: The endoscopy Global Rating Scale (GRS) is a web-based self-assessment quality improvement (QI) tool that provides a framework for service improvement. Widespread use of the GRS in adult endoscopy services in the United Kingdom (UK) has led to a demonstrable improvement in quality. The adult GRS is not directly applica...

Background Genetic studies have strongly linked autophagy to Crohn’s disease (CD), and stimulating autophagy in CD patients may be therapeutically beneficial. The aim of this study was to evaluate the effect of current inflammatory bowel disease (IBD) drugs on autophagy and investigate molecular mechanisms of action and functional outcomes in relat...

Background Robust epidemiological data on paediatric inflammatory bowel disease (PIBD; IBD diagnosed <16 years of age) is vital to organising current healthcare provision and planning future service design. Historically, Scotland has the highest incidence of PIBD in the UK and one of the highest worldwide, however data on prevalence is lacking. We...

Background A recent systematic review reports stabilising or falling IBD incidence in Western countries with an overall prevalence in excess of 0.3%.¹ However, the true prevalence may be under-reported due to incomplete ascertainment of cases. We therefore conducted an extensive multi-parameter search strategy, manually confirming all diagnoses thr...

Inflammatory bowel disease (IBD), which includes Crohn’s disease (CD) and ulcerative colitis, is characterized by chronic inflammation of the gastrointestinal tract. The etiology involves a combination of genetic and environmental factors resulting in abnormal immune responses to intestinal microbiota. Genetic studies have strongly linked genes inv...

en Linked Content This article is linked to Philpott et al papers. To view these articles visit https://doi.org/10.1111/apt.14573 and https://doi.org/10.1111/apt.14954.

The safety, clinical efficacy and cost-effectiveness of biosimilar infliximab in adult inflammatory bowel disease (IBD) have now been extensively shown. Limited data has been collected in the paediatric setting. We report nationwide, prospective, clinical safety and effectiveness data for patients from all three Scottish paediatric IBD (PIBD) netwo...

Background Stricturing duodenal Crohn’s disease (CD) is a rare but serious presentation of CD causing significant morbidity. There are no data on its incidence rate in paediatric CD, and only estimates for adult CD. Our aim is to provide the first incidence data and case studies outlining this severe presentation in children. Methods A regional co...

Genetic defects that affect intestinal epithelial barrier function can present with very early-onset inflammatory bowel disease (VEOIBD). Using whole-genome sequencing, a novel hemizygous defect in NOX1 encoding NAPDH oxidase 1 was identified in a patient with ulcerative colitis-like VEOIBD. Exome screening of 1,878 pediatric patients identified fu...

Background Biosimilar infliximab became available in the UK in 2015. Paediatric experience to date on its use is limited. We prospectively evaluated the safety and efficacy of biosimilar infliximab (Remsima) in two paediatric gastroenterology networks in patients with inflammatory bowel disease. Methods Prospective clinical data were collected fro...

Importance Blood markers and fecal calprotectin are used in the diagnostic workup for inflammatory bowel disease (IBD) in pediatric patients. Any added diagnostic value of these laboratory markers remains unclear. Objective To determine whether adding laboratory markers to evaluation of signs and symptoms improves accuracy when diagnosing pediatri...

Aim of study: To describe the complications in children with paediatric inflammatory bowel disease (PIBD) undergoing intestinal surgical intervention during childhood in a regional paediatric surgery centre. There is a paucity in the literature concerning complication following PIBD surgery. Methods: A surgical audit database was utilised to study...

Aim of study: To describe post-transition surgical outcomes of children with paediatric inflammatory bowel disease (PIBD) in a regional centre. There is a paucity in the literature concerning surgical outcomes of PIBD patients post-transition into adult services. Methods: A surgical audit database was utilised to study surgeries in PIBD patients fr...

Aim To develop a paediatric endoscopy GRS (P-GRS) as a quality improvement tool which would also define standards for accreditation of paediatric endoscopy services. Methods A P-GRS working group was established in May 2015 and the membership of this group evolved to include representatives from the BSPGHAN endoscopy working group, district genera...

Background: Glucocorticoids are a mainstay of inflammatory bowel disease (IBD) treatment, with oral tapering courses frequently used to induce remission or control flares. Impairment of the hypothalamic-pituitary-adrenal (HPA) axis, resulting in adrenal suppression (AS), is an established side effect of exogenous glucocorticoids. Currently however...

Background: Autophagy is an intracellular process that degrades damaged or aged proteins and organelles to maintain cellular homeostasis. Defective autophagy has been strongly linked to inflammatory bowel disease (IBD) pathogenesis, with evidence that enhancing autophagy may be therapeutically beneficial by regulating inflammation and clearing inte...

Background: Inflammatory bowel disease (IBD) presents in childhood in up to 15% of cases. Paediatric onset IBD (PIBD) has a more extensive and dynamically changing phenotype and a faster rising incidence than adult-onset IBD. We aimed to evaluate rates of treatment refractory disease at and then following transition to adult services. Methods: A pr...

Background: Faecal calprotectin has an established role in the investigation of paediatric inflammatory bowel disease (PIBD) but may not be available. Availability is often hampered by non-provision of samples or delayed by long turnaround times. Exploration of other indices which may indicate a strong likelihood of PIBD in the absence of faecal bi...

Background: Genital lymphoedema is caused by inflammation and granuloma formation in the lymphatic system and is recognised as a presentation of cutaneous metastatic Crohn's disease (CD). It can precede luminal presentation by months to years, particularly in younger patients; many children with cutaneous CD have genital involvement. Despite severa...

Genetic association studies have identified 215 risk loci for inflammatory bowel disease, thereby uncovering fundamental aspects of its molecular biology. We performed a genome-wide association study of 25,305 individuals and conducted a meta-analysis with published summary statistics, yielding a total sample size of 59,957 subjects. We identified...

Inflammatory bowel disease (IBD) is characterised by chronic inflammation of the gastrointestinal tract. Medications such as corticosteroids, thiopurines, immunomodulators and biological agents are used to induce and maintain remission, however response to these drugs is variable and can diminish over time. Defective autophagy has been strongly lin...

Genetic association studies have identified 210 risk loci for inflammatory bowel disease 1–7 , which have revealed fundamental aspects of the molecular biology of the disease, including the roles of autophagy and Th17 cell signaling and development. We performed a genome-wide association study of 25,305 individuals, and meta-analyzed with published...

Purpose: Gain-of-function (GOF) mutations in the signal transducer and activator of transcription 1 (STAT1) result in unbalanced STAT signaling and cause immune dysregulation and immunodeficiency. The latter is often characterized by the susceptibility to recurrent Candida infections, resulting in the clinical picture of chronic mucocutaneous cand...

Inflammatory bowel disease (IBD) is a chronic, relapsing-remitting disease which presents in childhood or adolescence in a significant proportion of cases.1 Even those patients who remain in remission with an uncomplicated course in paediatric services need to progress to adult services in anticipation of the natural disease course and for surveill...

Introduction Biliary atresia (BA) is a rare and poorly understood liver disease of infancy that is fatal if not treated through early biliary drainage via the Kasai procedure. BA surgery was rationalised to three UK centres in 2002 following data supporting improved outcomes in institutions performing greater than five Kasai procedures per year.1We...